State Industries Water Heater STC 077 User Manual

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SUF Service Handbook  
TABLE OF CONTENTS  
STC-077  
Introduction . . . . . . . . . . . . . . . . . . . 2  
Troubleshooting (continued)  
Blower . . . . . . . . . . . . . . . . . . . . . . . 25  
Pressure Switch Performance . 26 – 27  
120 VAC to Ignitor . . . . . . . . . . . . . . 28  
Ignitor Resistance. . . . . . . . . . . . . . . 29  
Gas Valve Test . . . . . . . . . . . . . . . . . 30  
Gas Pressure Check . . . . . . . . . . . . 31  
Installation  
Clearances . . . . . . . . . . . . . . . . . . . . . 3  
Gas Requirements . . . . . . . . . . . . . . . 3  
Venting . . . . . . . . . . . . . . . . . . . . . 4 – 8  
Air Requirements . . . . . . . . . . . . 9 – 11  
Contaminated Air . . . . . . . . . . . . . . . 12  
Flammable Items . . . . . . . . . . . . . . . 12  
Multiple Unit Piping. . . . . . . . . . . . . . 13  
Condensation . . . . . . . . . . . . . . . . . . 14  
Component Information  
Orifice Tables . . . . . . . . . . . . . . . . . . 32  
Pressure Switches . . . . . . . . . . 33 – 34  
Operation  
Wiring Diagrams . . . . . . . . . . . . . . 35  
Sequence of Operation . . . . . . . . . . 15  
Controls . . . . . . . . . . . . . . . . . . . . . . 16  
Circuit Boards. . . . . . . . . . . . . . . . . . 17  
Service Aids . . . . . . . . . . . . . . . . . . 36  
SUF Muffler . . . . . . . . . . . . . . . . . . . 37  
Questions & Answers . . . . . . . . . . 38  
Error Codes. . . . . . . . . . . . . . . . . . . 39  
Service Checklist . . . . . . . . . . . . . . 40  
Parts Lists  
Troubleshooting  
Pre-Service. . . . . . . . . . . . . . . . . . . . 18  
120 VAC to Control. . . . . . . . . . . . . . 18  
Transformer . . . . . . . . . . . . . . . 19 – 20  
ECO Check . . . . . . . . . . . . . . . 21 – 22  
Temperature Probe. . . . . . . . . . . . . . 23  
Pressure Switch Continuity . . . . . . . 24  
Models 100 – 150, 100 – 199,  
and 100 – 240 . . . . . . . . . . . 41 – 43  
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S U F  
S E R V I C E  
H A N D B O O K  
I N T R O D U C T I O N  
INTRODUCTION  
This service handbook is designed to aid in servicing and troubleshooting State SUF 150, 199 and 240 water heaters.  
No duplication or reproduction of this book may be made without the express written authorization of the State Water  
Heaters Company.  
The following text and illustrations will provide you with a step by step procedure to verify proper installation, operation  
and troubleshooting procedures. Additional quick reference data is included to assist you in servicing this product.  
The information contained in this handbook is designed to answer commonly faced situations encountered in the oper-  
ation of the SUF product line and is not meant to be all inclusive. If you are experiencing a problem not covered in this  
handbook, please contact the State Technical Information Department at 1-800-365-0577 or your local State Represen-  
tative for further assistance. This handbook is intended for use by licensed plumbing professionals and reference  
should be made to the instruction manual accompanying the product. This handbook contains supplemental informa-  
tion to the SUF instruction manual.  
Qualifications: Installation or service of this water heater requires ability equivalent to that of a licensed tradesman in  
the field involved. Plumbing, venting, gas supply and electrical testing skills are required.  
Tools Required:  
• Phillips head and flat tip screw drivers  
• Set of marked drill bits  
• Electric multimeter tester  
• Gas pressure gauge or manometer (gauge — part number 8099-2)  
• Water pressure gauge (part number 4798)  
• Digital manometer or draft gauge  
• Thermometer (part number 4870 — range 0 thru 220°F)  
1
1
/2”, 1” and 1 /8” sockets  
• Pipe wrench for union disconnect  
NOTE Also, have a copy of the instruction manual for the model and series SUF that you are servicing.  
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S U F  
S E R V I C E  
H A N D B O O K  
I N S T A L L A T I O N  
INSTALLATION  
CLEARANCES  
This portion of the handbook will review  
often overlooked installation require-  
ments. The installation manual covers  
these items in detail. SUF water heaters  
are approved for installation on com-  
bustible flooring. The minimum clear-  
ance to combustibles or non-  
combustibles is 0 inches from the sides  
and rear, 0 inches from vent piping, and  
1.5 inches from the top cover. A 24 inch  
clearance for all serviceable parts is  
recommended. Clearances may vary  
between SUF models. See installation  
manual or the label on the heater for  
your specific model.  
GAS REQUIREMENTS  
N O T E : Pressure without capacity will result in lockout. Follow the piping guidelines in the  
installation manual. The supply gas pressure is normally measured at the dirt leg or at the inlet gas  
pressure tap on the gas valve. This reading must be measured with ‘flowing’ gas.  
The manifold gas pressure is measured at the manifold pressure tap on the gas valve when the  
gas is flowing. The gas valves used on all SUF water heaters are 24 VAC combination step open-  
ing gas valves. They incorporate the main valve and pressure regulator into one body.  
REGULATED GAS SUPPLY LINE  
PRESSURE REGULATOR  
ADJUSTMENT  
(COVER SCREW)  
GAS VALVE ON/OFF  
MAIN GAS  
SHUTOFF VALVE  
TH & TR TERMINALS  
(MAIN VALVE)  
INLET PRESSURE  
TAP  
DIRT LEG TEE  
PIPE CAP  
MANIFOLD  
PRESSURE TAP  
GAS INLET  
GAS OUTLET  
SUF 240  
SUF 150 & 199  
SUF 150 & 199  
PROPANE GAS  
GAS SUPPLY SPECIFICATIONS  
NATURAL GAS  
NATURAL GAS  
12.0 (3 kPa)  
7.0 (1.75 kPa)  
5.5 (1.37 kPa)  
4.0 (1 kPa)  
12.0 (3 kPa)  
7.0 (1.75 kPa)  
4.5 (1.12 kPa)  
3.5 (0.8 kPa)  
14.0 (3.45 kPa)  
11.0 (2.74 kPa)  
11.0 (2.74 kPa)  
10.0 (2.5 kPa)  
Max  
. Gas Supply Pressure Inches W.C.  
Inches  
Nominal Gas Supply Pressure  
Minimal Gas Supply Pressure  
W.C.  
W.C.  
Inches  
Inches  
Manifold Pressure  
W.C.  
State Water Heaters  
Ashland City, Tennessee © 2004  
Technical Training Department  
STC-077  
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S U F  
S E R V I C E  
H A N D B O O K  
I N S T A L L A T I O N  
VENTING  
Equivalent Feet of Pipe Intake or Exhaust  
VENT LENGTH TABLE  
NUMBER OF 90°  
ELBOWS  
3” MINIMUM  
PIPE (FEET)  
3” MAXIMUM  
PIPE (FEET)  
4” MAXIMUM  
PIPE (FEET)  
7
7
7
7
7
7
45  
40  
35  
30  
--  
115  
110  
105  
100  
95  
ONE (1)  
TWO (2)  
THREE (3)  
FOUR (4)  
FIVE (5)  
SIX (6)  
--  
90  
4-inch PVC may be used for a MAXIMUM intake of ONE HUNDRED TWENTY (120) EQUIVALENT  
FEET and a MAXIMUM exhaust of ONE HUNDRED TWENTY (120) EQUIVALENT FEET. The  
maximum number of 90° elbows with the 4-inch venting is six (6) on the intake and six (6) on the  
exhaust. A 90° elbow is equal to five (5) equivalent feet of pipe. One (1) 90° elbow is equal to two  
(2) 45° elbows. Any venting configuration using less than 50 equivalent feet should use 3-inch vent-  
ing. See Vent Length Table.  
The 3-inch venting terminals (provided) must be used with the 4-inch venting by adding 4 x 3  
reducing coupling at the venting terminals. A reducing coupling is also needed immediately after  
the condensate elbow (exhaust) and immediately before the 3-inch blower adapter (intake) if direct  
venting is installed. See Vent Length Table.  
DIRECT VENTING  
The air intake provided on the unit contains a mesh screen (see Figure below) to prevent large par-  
ticles from entering the unit.  
3” (7.6CM) 45° PVC ELBOW WITH MESH SCREEN  
WARNING WHEN THE UNIT IS TO  
BE SETUP AS A DIRECT VENT, THE  
MESH SCREEN MUST BE REMOVED.  
THE INLET VENT PIPE MAY THEN BE  
GLUED TO THE AIR INTAKE (see follow-  
ing Figure) PROVIDED ON THE UNIT.  
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S U F  
S E R V I C E  
H A N D B O O K  
I N S T A L L A T I O N  
VENTING CONFIGURATIONS  
SEALED DIRECT  
VENT SIDEWALL  
INDOOR CONVENTIONAL  
VERTICAL  
INDOOR CONVENTIONAL  
SIDEWALL  
SEALED DIRECT  
VENT VERTICAL  
SEALED DIRECT VENT  
HORIZONTAL INTAKE  
VERTICAL EXHAUST  
SEALED DIRECT VENT  
VERTICAL INTAKE  
HORIZONTAL EXHAUST  
SEALED DIRECT VENT  
W/ CONCENTRIC VENT  
VERTICAL TERMINA-  
SEALED DIRECT VENT  
W/ CONCENTRIC VENT  
HORIZONTAL TERMINATION  
VENTING MATERIALS  
This unit can be vented using only PVC (Class 160, ASTM D-2241; Schedule 40, ASTM D-1785; or  
Cellular Core Schedule 40 DWV, ASTM F-891), Schedule 40 CPVC (ATSM F-411), or ABS (ASTM  
D-2661) pipe. The fittings, other than the TERMINATIONS should be equivalent to PVC-DWV fit-  
tings meeting ASTM D-2665 (Use CPVC fittings, ASTM F-438 for CPVC pipe and ABS fittings,  
ASTM D-2661/3311 for ABS pipe. If CPVC or ABS pipe and fittings are used, then the proper  
cement must be used for all joints, including joining the pipe to the Termination Tee (PVC Material).  
PVC Materials should use ASTM D-2564 Grade Cement; CPVC Material should use ASTM F-493  
Grade Cement and; ABS Materials should use ASTM D-2235 Grade Cement.  
For water heaters in locations with high ambient temperatures (above 100°F) and/or insufficient  
dilution air, it is recommended that CPVC or ABS pipe and fittings (MUST USE SUPPLIED VENT  
TERMINAL) be used.  
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S U F  
S E R V I C E  
H A N D B O O K  
I N S T A L L A T I O N  
CONCENTRIC VENT TERMINATION  
The concentric vent termination kit, Part No. 9003910005 can be used on SUF 150 – 240 Ultra  
Force water heaters. It adds zero equivalent feet to the vent system. Below are some general appli-  
cation and installation guidelines for the concentric vent kit. Refer to the accompanying literature  
and the water heater installation manual for complete venting installation instructions.  
This concentric vent termination kit may be used with 3 or 4 in. diameter pipe systems. When con-  
necting to a 4 in. diameter pipe system a 3 x 4 in. field supplied reducer is to be installed at the  
intake and exhaust connection of the concentric vent termination kit. See water heater installation  
and operation manual for venting specification  
1
1
Dimension 21 /8 in. may be lengthened to 60 in. maximum. Dimension 21 /8 in. may also be short-  
ened by cutting the pipes, provided in the kit, to 12 in. minimum. Dimension 39 will change accord-  
1
ingly as dimension 21 /8 in. is lengthened or shortened  
Horizontal  
Installation  
Vertical Installation  
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S U F  
S E R V I C E  
H A N D B O O K  
I N S T A L L A T I O N  
VENTING CLEARANCES  
This illustrates the exterior clearances for these SUF units when installed as direct vent heaters.  
N O T E : 24 inches between inlet and outlet is a MINIMUM. Greater distance is recommended.  
In colder climates increasing the 24” minimum to a maximum practical distance will reduce the  
possibility of frost over from side winds blowing exhaust vapors into the air intake.  
SUF MODEL 150 – 199  
SUF MODEL 240  
State Water Heaters  
Ashland City, Tennessee © 2004  
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S U F  
S E R V I C E  
H A N D B O O K  
I N S T A L L A T I O N  
EXTERIOR SIDEWALL CLEARANCES  
Horizontal Vent (Using Room Air for Combustion)  
Horizontal Direct Vent (Using Outdoor Air for Combustion)  
When multiple units are directly vented through a wall, all intake vent terminals must be no lower  
than the highest exhaust vent terminal.  
CAUTION DO NOT TERMINATE THE VENTING WHERE NOISE FROM THE EX-  
HAUST OR INTAKE WILL BE OBJECTIONABLE. THIS INCLUDES LOCATION CLOSE TO  
OR ACROSS FROM WINDOWS AND DOORS. AVOID ANCHORING THE VENT AND  
INTAKE PIPES DIRECTLY TO FRAMED WALLS, FLOORS OR CEILINGS UNLESS RUB-  
BER ISOLATION PIPE HANGERS ARE USED. THIS PREVENTS ANY VIBRATIONS  
FROM BEING TRANSMITTED INTO THE LIVING SPACES.  
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S U F  
S E R V I C E  
H A N D B O O K  
I N S T A L L A T I O N  
AIR REQUIREMENTS  
MINIMUM AIR FOR COMBUSTION  
10 Cubic Feet of Air Per 1000 BTUH  
Stoichiometric or theoretical complete combustion requires 10 cubic feet of air per 1000 BTUH of  
gas input. The National Fuel Gas Code also recommends an additional 2.5 cu.ft. of “excess air”.  
This 12.5 cu.ft. minimum supply air per 1000 BTUH input applies to natural and propane gas mod-  
els.  
The National Fuel Code also specifies minimum make-up air opening sizes for various building  
installations (Ref: NFPA 54, ANSI Z223.1, sec 5.3).  
MAKE-UP AIR  
Direct Vent Installation  
This model is approved for direct venting either horizontally or vertically or conventional venting  
horizontal or vertical. Direct venting avoids using room air for combustion and eliminates the need  
for additional air intake ducts.  
State Water Heaters  
Ashland City, Tennessee © 2004  
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S U F  
S E R V I C E  
H A N D B O O K  
I N S T A L L A T I O N  
MAKE-UP AIR  
Direct Communication  
A fresh supply of make-up air for combustion can be supplied to the heater through make-up air  
openings, which directly communicate with the out of doors. Two openings are required — one  
within 12 inches of the top of the enclosure and one within 12 inches of the bottom of the enclosure.  
Each opening shall have a free area of not less than 1 square inch per 4000 BTUH of the total input  
of all appliances within the enclosure.  
The lower opening is primarily providing combustion air. The upper opening is providing vent dilu-  
tion air and acts as a relief opening for flue gases should the vent become obstructed or a down  
draft condition occur.  
MAKE-UP AIR  
Vertical Ducts  
Often it is more practical to install vertical make-up air ducts to the outdoors. Again, two openings  
are required — within 12 inches (30 cm) of the top of the enclosure and one within 12 inches (30  
cm) of the bottom of the enclosure. Each opening shall have a free area of not less than 1 square  
inch per 4000 BTUH of the total input of all appliances within the enclosure.  
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S U F  
S E R V I C E  
H A N D B O O K  
I N S T A L L A T I O N  
MAKE-UP AIR  
Horizontal Ducts  
When the heater is installed in an interior room with no roof access for vertical ducts, horizontal  
make-up ducts should be installed. When using horizontal ducts, two openings are required —  
within 12 inches (30 cm) of the top of the enclosure and one within 12 inches (30 cm) of the bottom  
of the enclosure. Each opening shall have a free area of not less than 1 square inch per 2000  
BTUH of the total input of all appliances within the enclosure.  
INSUFFICIENT MAKE-UP AIR  
Backdraft  
Insufficient make-up air is a major cause of combustion problems. One common example is in a  
restaurant installation where exhaust vent equipment was not considered in sizing make-up air  
requirements. This may result in air being backdrafted by the restaurant exhaust equipment  
through the heater causing flue gas spillage, flame roll out, improper combustion, inconsistent pilot  
operation, and/or erratic heater shutdown.  
A possible solution to this situation would be to use a SUF with direct venting.  
A less common service issue associated with a backdraft or negative pressure room would be the  
opening or closing of air pressure switches. This may result in erratic or no heater operation.  
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S U F  
S E R V I C E  
H A N D B O O K  
I N S T A L L A T I O N  
CONTAMINATED AIR  
RUST  
=
CHIPS  
Along with adequate make-up air, the quality of the air is important. Contaminants in combustion air  
can lead to premature heater failure. Vapors from bleaches, soaps, salts, etc. are drawn into the  
combustion chamber with the make-up air and, once fired, mix with water vapor in the gasses to  
form extremely corrosive hydrochloric or hydrofluoric acid and other corrosive by-products. Dust  
drawn in may build up on the blower or clog the main burner ports. Also, be certain to examine the  
exterior area around the air intake of a direct vent installation for the contaminants.  
FLAMMABLE ITEMS  
Flammable items or pressurized containers or any other potentially hazardous articles must never  
be placed on or adjacent to the heater. Open containers of flammable material should not be stored  
or used in the same room with the heater or in the area of the exterior air intake of a direct vent  
installation. Direct venting does not eliminate the need to remove flammable or corrosives from the  
area surrounding the heater.  
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S U F  
S E R V I C E  
H A N D B O O K  
I N S T A L L A T I O N  
MULTIPLE UNIT — WATER PIPING  
NOTES APPLY TO ALL SYSTEMS:  
*ADD GATE VALVES TO INLET AND OUTLET OF EACH  
UNIT FOR ISOLATION FLEXIBILITY. LOCATE AT THE  
SAME POINT FROM TEE.  
** ADD THERMAL EXPANSION TANK TO COLD WATER  
SUPPLY IF NECESSARY.  
CONDENSATION HOSE MUST BE ALLOWED TO DRAIN.  
NOTE: T&P VALVES MUST BE PIPED TO OPEN DRAIN OR  
PER LOCAL CODE  
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S U F  
S E R V I C E  
H A N D B O O K  
I N S T A L L A T I O N  
CONDENSATION  
The average dewpoint of natural gas flue products is 127° F. Propane flue products is 119° F. With  
70° F ambient air temperature and 180° F stored water temperature, exhaust gas will be approxi-  
mately 140° F. Recommended starting point for water storage is 120° F.  
The extra high thermal efficiency of the SUF will result in condensation in the flue passage. The fol-  
lowing answers common questions about this condensation.  
CAN I DRAIN THIS CONDENSATION TO A FLOOR DRAIN? The “Corrosion Resistance of Cast  
Iron Soil Pipe” by the Ductile Metals Association (formally the Cast Iron Soil Pipe Institute) states  
that:  
“Internal corrosion of cast iron soil pipe and fittings can be caused by strong acids or other reagents  
having an acidity of pH 4.3 or less if allowed to contact cast iron pipe for an extended period of time  
without sufficient dilution to raise the pH valve about 4.3. By avoiding low pH discharges, internal  
corrosion problems can be limited or eliminated, assuring the owner many years of service.”  
WHAT ABOUT THE pH VALUES OF CONDENSATE AND SODA POP? The pH of the SUF con-  
densate average 4.5 which is approximately 4 times less concentrated than the limit of 4.3 recom-  
mended by the DMA. Any water flow in the drain rapidly dilutes the condensate even more. A can  
of leading carbonated cola drink measured a pH of 2.5 which is 300 times more concentrated than  
the SUF condensate.  
WHAT DOES THE pH SCALE MEAN? The pH value is a measure of acidity of alkalinity. A pH of  
7 is neutral. Numbers from 7 to 1 indicate increasing acidity and numbers from 7 to 14 indicate  
increasing alkalinity. The pH scale is similar to the Richter scale used to measure earthquakes.  
Each number indicates a change of 10 times the concentration of the previous value. A pH 6 is 10  
times more concentrated than a pH 7, a pH 5 is (10x10) 100 times pH 7 and pH 4 is (10x10x10)  
1,000 times pH 7, etc.  
WHAT ABOUT CONDENSATE NEUTRALIZERS? Condensate neutralizers are usually not nec-  
essary. A condensate neutralizer is easy to make by filling a short length of 2” or 3” PVC pipe with  
landscape marble chips, capping it and installing it in series with the condensate drain of the equip-  
ment. Most commercial neutralizers are off the market because of poor demand for the product.  
Condensation from the exhaust vent piping and tank internal flue way must be allowed to drain. A  
“blocked flue” indication will often be your first indication that condensate is not draining.  
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S U F  
S E R V I C E  
H A N D B O O K  
O P E R A T I O N  
OPERATION  
SEQUENCE OF OPERATION  
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S U F  
S E R V I C E  
H A N D B O O K  
O P E R A T I O N  
CONTROLS  
NORMAL INDICATIONS / READINGS / SETTINGS  
During Call for Heat  
• On/Off switch in the “on” position  
DISPLAY PANEL (CONTROL PANEL)  
• Water Temperature F° — current average  
tank water temperature displayed  
• 120 VAC LED light on  
• 24 VAC LED light on  
• High Limit/Vent Switch LED light on  
• Blower (while blower is running) LED light  
on  
• Air Pressure Switch (while blower is  
running) LED light on  
• Control Status LED light on  
• Gas Valve (during ignition period and  
heating cycle) LED light on  
The water temperature inside the tank must be below the current temperature setting to activate a  
call for heat. Pressing the Set/Reset button approximately 4 – 6 seconds after powering up the  
water heater will reveal the current temperature setting. See the instructions below for how to view  
or change temperature settings.  
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S U F  
S E R V I C E  
H A N D B O O K  
O P E R A T I O N  
CIRCUT BOARDS  
DISPLAY CIRCUIT BOARD  
IGNITION CIRCUIT BOARD  
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S U F  
S E R V I C E  
H A N D B O O K  
T R O U B L E S H O O T I N G  
TROUBLESHOOTING  
PRE-SERVICE TIPS  
CHECK THAT:  
• Insure 120 VAC power supply has correct polarity — check neutral  
(white) wire to ground with volt meter. It should read “0” volts.  
Tank is full of water  
• Exhaust and intake vent do not exceed allowable limits  
• All plugs into boards are secure  
• Condensate hose is drained and open  
• Proper (natural or propane) gas is supplied  
SUF SERVICE HANDBOOK  
120 VAC TO CONTROL  
STEP 1 120 VAC TO CONTROL BOARD  
STEP 1: CHECK FOR 120 VAC TO CONTROL BOARD CN1 TERMINAL.  
Condition:  
• Disconnect plug from CN1 terminal.  
• On/Off switch is on.  
Check for 120 VAC black wire terminal white wire on plug.  
IF…  
THEN  
check On/Off switch, turn switch on, replace On/Off switch if defective, restore  
power to the water heater.  
120 VAC is not present  
120 VAC is present  
reconnect CN1 plug, continue to Step 2.  
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S U F  
S E R V I C E  
H A N D B O O K  
T R O U B L E S H O O T I N G  
TRANSFORMER  
STEP 2 120 VAC TO TRANSFORMER  
STEP 2: CHECK FOR 120 VAC TO TRANSFORMER FROM PIN 1 AND 2 ON CONTROL  
BOARD CN4 TERMINAL.  
Condition:  
• Disconnect CN4 plug from control board.  
• On/Off switch is on.  
Check for 120 VAC between pin 1 and 2 at CN4 on the control board as illustrated above. Perform  
this test with the CN4 plug disconnected and the On/Off switch turned on.  
IF…  
THEN  
check CN1 plug connection  
replace control board if Step 1 has been performed and results were successful.  
120 VAC is not present  
120 VAC is present  
reconnect CN4 plug to control board, continue to Step 3.  
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S U F  
S E R V I C E  
H A N D B O O K  
T R O U B L E S H O O T I N G  
TRANSFORMER (CONTINUED)  
STEP 3 24 VAC FROM TRANSFORMER  
STEP 3: CHECK FOR 24 VAC AT TRANSFORMER CN4 PLUG ON CONTROL BOARD.  
Condition:  
• CN4 is plugged into control board.  
• On/Off switch is on.  
Insert meter probes into back of CN4 plug on pins 3 and 4 (blue and yellow wires) with CN4  
plugged in and power on.  
IF…  
THEN  
24 VAC is not present  
24 VAC is present  
replace transformer if Steps 1 and 2 were performed and results were successful.  
continue to Step 4.  
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S U F  
S E R V I C E  
H A N D B O O K  
T R O U B L E S H O O T I N G  
ECO CHECK  
STEP 4 24 VAC TO ECO  
STEP 4: CHECK FOR 24 VAC BETWEEN PIN 4 ON CONTROL BOARD TERMINAL CN3 AND  
GROUND.  
Condition:  
• Disconnect CN3 plug from control board.  
• On/Off switch is on.  
Check for 24 VAC between pin 4 of the CN3 terminal on the control board and ground.  
IF…  
THEN  
replace the control board if Steps 1, 2, and 3 have been performed and the results  
were successful.  
24 VAC is not present  
24 VAC is present  
continue to Step 5.  
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S U F  
S E R V I C E  
H A N D B O O K  
T R O U B L E S H O O T I N G  
ECO CHECK (CONTINUED)  
STEP 5 24 VAC FROM ECO  
STEP 5: CHECK FOR 24 VAC BETWEEN PIN 1 ON CN3 PLUG AND GROUND.  
Condition:  
• Reconnect CN3 plug to control board.  
• On/Off switch is on.  
Insert one meter probe into the back of CN3 plug pin 1, check for 24 VAC between here and ground  
with CN3 plugged in and power on. (See illustration above for pin number locations.)  
IF…  
THEN  
make sure water temperature in tank is below 160° F, press Set/Reset button on  
display panel, replace upper temperature/ECO probe if tank water temperature is  
below 160 and Step 4 has been performed and results were successful.  
24 VAC is not present  
24 VAC is present  
continue to Step 6.  
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S U F  
S E R V I C E  
H A N D B O O K  
T R O U B L E S H O O T I N G  
TEMPERATURE PROBE  
STEP 6 TEMPERATURE PROBE RESISTANCE  
UPPER  
LOWER  
TEMPERATURE  
PROBE PLUG  
TEMPERATURE  
PROBE PLUG  
STEP 6: CHECK RESISTANCE OF THERMISTOR IN UPPER AND LOWER TEMPERATURE  
PROBES.  
Condition:  
• Disconnect CN3 and CN8 plugs from control board.  
• On/Off switch is off.  
• Multimeter is set to lowest ohms scale above expected resistance.  
Check resistance between black wire connects on CN3 and CN8 plugs as shown in illustration  
above.  
IF…  
THEN  
ohm reading does not approximately correspond to table at given replace temperature probe if thermistor is open.  
temperatures  
shorted, or resistance value is off significantly.  
continue to Step 7.  
ohm reading does approximately correspond to table at given  
temperatures  
NOTE: The upper and lower temperature probes contain  
thermistors which are heat sensitive resistors. The control  
board interprets changes in thermistor resistance as  
changes in water temperature.  
WATER TEMP  
OHMS RESISTANCE  
°C  
°F  
3
21  
40  
70  
26,435  
11,974  
These thermistors are very reliable and should only be  
replaced when:  
37.5  
49  
100  
120  
5,862  
3,780  
The resistance test indicates an “open” (infinite resistance)  
or a “direct short” (no resistance) circuit.  
54.5  
60  
130  
140  
3,066  
2,503  
The nature of the service problem is temperature control  
and the resistance readings are significantly off when com-  
pared to the values in the table here at the given tempera-  
ture.  
71  
82  
160  
180  
1,698  
1,177  
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S U F  
S E R V I C E  
H A N D B O O K  
T R O U B L E S H O O T I N G  
PRESSURE SWITCH CONTINUITY  
STEP 7 PRESSURE SWITCH CONTINUITY TEST  
STEP 7: CHECK FOR CONTINUITY BETWEEN PRESSURE SWITCH TERMINALS WITH  
WIRES REMOVED.  
Condition:  
• On/Off switch is off.  
• All wires are disconnected from all pressure switches.  
• Multimeter is set to lowest ohms scale.  
IF…  
THEN  
blocked inlet switch does not show continuity  
blocked inlet switch does show continuity  
blower proving switch does show continuity  
blower proving switch does not show continuity  
replace switch.  
continue.  
replace switch.  
continue.  
check for minimum supply gas  
pressure of  
5.0” W.C. natural gas  
9.0” W.C. LP gas  
low gas pressure switch does not show continuity  
replace switch if gas pressures  
are above these minimums.  
low gas pressure switch does show continuity  
continue.  
blocked outlet pressure switch does not show continuity  
replace switch.  
reconnect all wires to pressure  
switches; continue to Step 8.  
blocked outlet pressure switch does show continuity  
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S U F  
S E R V I C E  
H A N D B O O K  
T R O U B L E S H O O T I N G  
BLOWER  
STEP 8  
120 VAC TO BLOWER  
STEP 8: CHECK FOR 120 VAC TO BLOWER FROM CN2 PLUG PIN 1 AND 2.  
Condition:  
• Reconnect all plugs to control board.  
• On/Off switch is on.  
• Call for heat is activated.  
Insert meter probes into back of CN2 plug on pins 1 and 2 with CN2 plugged in, power on, and a  
call for heat activated.  
IF…  
AND  
THEN  
120 VAC is not  
present  
replace the control board if call for heat is active and Step 7 has been  
performed and results were successful — continue to Step 9A.  
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S U F  
S E R V I C E  
H A N D B O O K  
T R O U B L E S H O O T I N G  
PRESSURE SWITCH PERFORMANCE  
STEP 9A TAKE AIR AND GAS PRESSURE READINGS.  
Blower prover and blocked outlet pressure  
Blower inlet pressure  
STEP 9A: CHECK PRESSURE AT SENSING PORTS ON BURNER, BLOWER INLET AND GAS  
VALVE.  
Condition:  
• All wires are reconnected to all pressure switches.  
• On/Off switch is on.  
• Call for heat is activated.  
• Blower is running during trial for ignition.  
Remove the air pressure sensing tubes from the sensing ports on the blower inlet and the burner.  
Using a digital manometer take a pressure reading with the blower running during a call for heat at  
both of these sensing ports. Take a supply gas pressure reading on the inlet side of the gas valve  
as outlined in Step 13.  
Record all 3 pressure readings and have them on hand. Continue to Step 9B.  
AMBIENT ROOM AIR PRESSURE  
N O T E : One side of the internal diaphragms on these pressure switches are vented to the  
room atmosphere. Due to this construction a negative or positive room air pressure can cause  
erratic switch operation and the water heater to shut down. If you suspect a pressure imbalance  
between the equipment room and the outdoor atmosphere, “zero” or calibrate your digital  
manometer to the equipment room ambient air pressure. With the manometer still on and  
calibrated to the equipment room air pressure take the manometer outdoors. If the pressure  
reading changes significantly you may have a pressure imbalance between the equipment room  
and the outdoor atmosphere. This pressure imbalance may need to be corrected before the water  
heater will operate properly.  
Insure the combustion/make-up air openings into the equipment room are properly sized. Check for  
leaks in ductwork on any nearby air handling equipment. If there is a kitchen vent hood installed in  
the building, insure it is properly balanced. Missing or worn fan belts on make up air fans to vent  
hoods can cause negative air pressure throughout the building.  
Direct vent installations DO NOT eliminate this potential problem.  
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S U F  
S E R V I C E  
H A N D B O O K  
T R O U B L E S H O O T I N G  
PRESSURE SWITCH PERFORMANCE (CONTINUED)  
STEP 9B PRESSURE SWITCH CONTINUITY TEST — OPERATIONAL  
SUF 240  
ONLY  
Air pressure switches  
Low gas pressure switch  
STEP 9B: CHECK FOR CONTINUITY BETWEEN PRESSURE SWITCH TERMINALS WITH  
WIRES REMOVED AND BLOWER RUNNING.  
Condition:  
• All wires are disconnected from all pressure switches — ends are taped off.  
• On/Off switch is on.  
• Call for heat is activated.  
• Blower is running during trial for ignition.  
• Multimeter is set to lowest ohms scale.  
The wires disconnected are energized with 24 VAC from the control board. Do not allow these  
wires to touch ground — use electrical tape to insulate wire connects during this test.  
Check for continuity with an ohm meter between terminals on all pressure switches with the wires  
removed and the blower running during a trial for ignition. Restart the water heater as needed.  
The pressure switches are wired together in a “series” circuit. For the water heater to continue to  
fire and satisfy a call for heat the control board must sense a closed pressure switch circuit.  
IF…  
THEN  
continuity is not present between terminals on  
one or more pressure switches — the switch  
contacts are open.  
if the pressure recorded in Step 9A is within the value shown in  
the table for the switch contacts to remain closed — replace the  
pressure switch.  
compare the pressure reading recorded in Step  
9A to the value given for that switch in the table  
on page 34.  
if the pressure recorded in Step 9A is not within the value shown  
in the table for the switch contacts to remain closed — check for/  
clear any restrictions in the vent and/or air intake piping, check  
for an excessive number of elbows or equivalent feet of pipe  
used in the vent and/or air intake piping.  
compare to value for correct Model and Series  
number in table.  
check for/restore minimum supply gas pressure — Step13.  
continue to Step 10.  
continuity is present.  
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S U F  
S E R V I C E  
H A N D B O O K  
T R O U B L E S H O O T I N G  
120 VAC TO IGNITOR  
STEP 10  
120 VAC TO IGNITOR  
STEP 10: CHECK FOR 120 VAC TO IGNITOR FROM PIN 1 AND 2 ON CONTROL BOARD  
TERMINAL CN5.  
Condition:  
• Disconnect CN5 plug from control board.  
• On/Off switch is on.  
• Call for heat is activated.  
• Perform test during ignitor warm up period.  
IF...  
THEN  
replace the control board if Steps 7 through 9B have  
been performed and results were successful.  
120 VAC is not present  
120 VAC is present  
continue to step 11.  
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S U F  
S E R V I C E  
H A N D B O O K  
T R O U B L E S H O O T I N G  
IGNITOR RESISTANCE  
STEP 11  
IGNITOR RESISTANCE CHECK  
STEP 11: CHECK RESISTANCE BETWEEN TWO WIRE CONNECTS AT CN5 IGNITOR PLUG  
END.  
Condition:  
• On/Off switch is off.  
• Disconnect CN5 ignitor plug from circuit board.  
• Multimeter is set to lowest ohms scale above 300 ohms.  
IF…  
THEN  
replace the ignitor.  
ohms reading taken is not between 50 – 300 ohms  
ohms reading taken is between 50 – 300 ohms  
reconnect CN5 plug, continue to Step 12.  
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S U F  
S E R V I C E  
H A N D B O O K  
T R O U B L E S H O O T I N G  
GAS VALVE TEST  
STEP 12  
24 VAC TO GAS VALVE  
SUF 240 ONLY  
STEP 12: CHECK FOR 24 VAC TO GAS VALVE DURING TRIAL FOR IGNITION.  
Condition:  
• All wires are reconnected.  
• On/Off switch is on.  
• Call for heat is activated.  
• Perform test at end of ignitor warm up period.  
Touch meter probes to wiring terminals on gas valve with wires from control board still connected  
during the ignitor warm up period.  
IF…  
AND  
THEN  
replace control board if Step 9A and 9B have  
been performed and results were successful.  
24 VAC is not present to gas valve  
24 VAC is present  
gas does not flow to burner check for/restore supply gas;  
check for/clear any restriction in the gas train;  
replace the gas valve if the valve will not open  
with 24 VAC applied.  
24 VAC is present  
gas does flow to burner  
continue to Step 13.  
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S U F  
S E R V I C E  
H A N D B O O K  
T R O U B L E S H O O T I N G  
GAS PRESSURE CHECK  
STEP 13 SUPPLY GAS PRESSURE TEST  
SUF 150, 199  
Propane  
SUF 150, 199  
Natural  
SUF 240 Natural  
Gas Valve  
Gas Valve  
STEP 13: CHECK AND ADJUST SUPPLY GAS PRESSURE.  
Attach manometer or gas pressure gauge to pressure tap on gas valve or use adapter to check  
pressure ahead of valve as near as possible to valve. All appliances being served by this gas sup-  
ply line should be operating.  
IF...  
THEN  
supply gas pressure is not between 5.0 and 14” W.C.  
natural gas or 11.0 and 14” W.C. propane  
adjust supply gas pressure (Recommended supply  
minimum is 7.0” W.C. for natural gas models)  
proper supply gas pressure is present  
continue to Step 14.  
STEP 14 MANIFOLD GAS PRESSURE TEST  
STEP 14: CHECK AND ADJUST MANIFOLD GAS PRESSURE.  
IF...  
THEN  
manifold gas pressure is not:  
natural gas models  
adjust manifold gas pressure to values given for model  
and fuel type (within 0.3” W.C. tolerance)  
if manifold gas pressure cannot be adjusted to  
maintain values given (within 0.3” W.C. tolerance)  
replace gas valve.  
3.5” W.C. ± 0.3” – SUF 155 & 199  
4.0” W.C. ± 0.3” – SUF 240  
propane gas models  
10.0” W.C. ± 0.3” – all propane gas models.  
manifold gas pressure is within tolerances given above  
ignition should occur.  
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S U F  
S E R V I C E  
H A N D B O O K  
C O M P O N E N T  
I N F O R M A T I O N  
COMPONENT INFORMATION  
FLAME SENSING ROD  
PART NUMBER  
192478  
FLAME SENSING CURRENT  
COMMENTS  
SUF 150, 199, & 240  
0.7 Micro Amp (µ)  
HOT SURFACE IGNITOR (HSI)  
PART NUMBER  
VOLTAGE  
120 VAC  
AMP  
OHMS COLD  
COMMENTS  
192638  
1.0  
50 – 300  
SUF 150, 199, & 240  
ORIFICE TABLE  
ORIFICE TABLE  
MAIN BURNER  
ORIFICE NO.  
MAIN ORIFICE SIZE  
INCHES  
AIR ORIFICES  
PT. NO.  
AIR ORIFICE  
SIZE — INCHES  
SUF MODEL  
150  
199  
192477-1  
192477-0  
192477-2  
192477-5  
192477-4  
0.235  
0.304  
0.360  
0.141”  
0.166”  
192450-1  
192450-0  
192450-2  
192450-5*  
192450-4*  
0.875  
1.031  
1.196  
0.872  
1.150  
240  
150 Prop  
199 Prop  
* -4 and -5 stamped with “P” for Propane  
N O T E : Hex head of main burner orifice is upstream end — gas flows out of tapered end.  
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S U F  
S E R V I C E  
H A N D B O O K  
C O M P O N E N T  
I N F O R M A T I O N  
PRESSURE SWTCHES  
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S U F  
S E R V I C E  
H A N D B O O K  
C O M P O N E N T  
I N F O R M A T I O N  
PRESSURE SWITCHES (CONTINUED)  
PRESSURE SWITCHES  
PART NUMBER / ACTIVATION PRESSURE  
Model  
Blocked Inlet  
Normally Closed  
Opens on a fall  
Blower Prover  
Normally Open  
Closes on a rise  
Low Gas Pressure  
Normally Open  
Closes on a rise  
Blocked Outlet  
Normally Closed  
Opens on a rise  
SUF 150  
193363-000 / -0.76”  
193355-000 / -1.80”  
193355-000 / -1.80”  
193363-000 / -0.76”  
193356-000 / -2.00”  
193356-000 / -2.00”  
193361-000 / -0.77”  
194706-000 / +1.00”  
194706-000 / +1.00”  
194706-000 / +1.00”  
194706-000 / +1.00”  
194706-000 / +1.00”  
194706-000 / +1.00”  
194706-000 / +1.00”  
N/A  
193362-000 / +2.60”  
193357-000 / +4.00”  
193357-000 / +4.00”  
193364-000 / +2.87”  
193357-000 / +4.00”  
193357-000 / +4.00”  
193357-000 / +4.00”  
N/A  
N/A  
SUF 199  
N/A  
N/A  
N/A  
SUF 240  
191149-005 / +5.20”  
†. Pressure values are given in inches of water column pressure (“W.C.).  
Negative pressure values in this table are preceded by a “-” minus sign and indicate pressure below  
atmospheric; in a vacuum. Positive pressures are preceded by a “+” plus sign and indicate pressure above  
atmospheric.  
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S U F  
S E R V I C E  
H A N D B O O K  
W I R I N G D I A G R A M S  
WIRING DIAGRAMS  
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S U F  
S E R V I C E  
S E R V I C E  
H A N D B O O K  
A I D S  
SERVICE AIDS  
1. This type product is polarity sensitive. Be certain that your electrical supply wire neutral has  
no voltage.  
2. This unit will produce condensation — quite heavily at times. The outlet drain hose must be  
allowed to drain. Exhaust Vent piping must also drain condensate. Code 11 error would imply  
that these must be checked.  
3. If the unit is located in a cold climate, take steps to ensure that exhaust vapors are not pulled  
into the air intake. Terminate both pipes on direct vent installations in the same area, but max-  
imize the distance between them.  
4. Do not combine vent these units.  
5. Pushing the reset button at random times may alter setting of the control. Note the sequence of  
operation comments on when to push this button.  
6. If you make a setting change, cycle the heater with this new setting to lock it into memory.  
7. The first items to check on a service call  
a. Correct venting installation  
b. Drainage of condensate from hose and exhaust vent pipe  
8. SUF models are certified to 6.800 ft. above sea level with the standard orifice — air and gas.  
9. The temperature display board indicates average tank water temperature. If one tank sensor is  
“open”, the indicator will display the active sensor temperature. (Because the top tank sensor  
also contains the high limit-24V-sensor, disconnecting this from the control board results in an  
error code (04).)  
10. Temperature and pressure relief valve operation. Weeping usually indicates thermal expan-  
sion. Large volume discharge usually indicates excessively hot water operation.  
11. SUF models are well within decimal level limits, but if you desire to lower the installation level  
approximately 6 decibels a muffler (Part No. 195334) may be installed in the exhaust vent.  
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S U F  
S E R V I C E  
S E R V I C E  
H A N D B O O K  
A I D S  
SUF MUFFLER  
N O T E S :  
1. Install muffler in vertical position only.  
2. Muffler must be a minimum of 8” from top of condensate elbow.  
3. The muffler inlet and outlet are 4” PVC. If venting with a 4” PVC, a 4” x 4” PVC coupling (field  
supplied) must be cemented to each end of the muffler. If venting with 3” PVC, a 4” x 3” PVC  
reducing coupling (field supplied) must be cemented to each end of muffler (see illustration  
above.)  
4. Cement muffler into a location using ASTM D-2564 grade cement.  
5. Secure muffler to suitable structure.  
6. Operate heater through 1 heat cycle to ensure there are no exhaust leaks and there is no  
obstruction of exhaust flow.  
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S U F  
S E R V I C E  
H A N D B O O K  
A N S W E R S  
Q U E S T I O N S  
A N D  
QUESTIONS AND ANSWERS  
Q. How much electrical power is required for a SUF water heater?  
A. The SUF models draw approximately 5.0 Amps Max.  
Q. When should SUF’s be delimed?  
A. Many variables affect the lime build up process including:  
Water temperature — the amount of lime accumulation during the same period of time will be  
nearly 2 times great if water is stored at 140 degrees F than at 120 degrees F. A 180° setting  
may accumulate seven times more lime — in a period of time — than at 140° setting.  
Volume of water — the more gallons flowing through the SUF, the more rapid the  
accumulation.  
Hardness — the harder the water the quicker lime build up occurs. 1 to 3.5 grains per gallons  
is “soft”, 3.5 to 7 grains per gallon is “moderate”, 7 to 10.5 grains per gallons is “hard” and  
10.5+ grains per gallon is “very hard”. (An aspirin is about 5 grains. One grain is equal to 17.1  
parts per million.)  
A. Deliming should be done when a slight rumbling or popping sound is detected when the main  
burner is on. Check for accumulation through the clean-out opening.  
Q. What effect will lime build-up have on the SUF water heater?  
A. One eighth inch of scale buildup on the heat exchanger may reduce efficiency as much as  
22%; a ¼ inch buildup, as much as 38%.  
Less efficient heat transfer means more heat exchanger expansion/contraction stress and pre-  
mature leakage.  
Because the heat transfer to the water is made through a (relatively) small diameter, coil type  
exchanger tube, expansion and contraction as well as the shape of the exchanger greatly  
reduces buildup on the heat transfer surface. The bottom of the tank should be checked for  
dislodged accumulation.  
Q. Anode rods (4) provide additional protection against corrosion. When should these be  
replaced?  
A. When large gouges or pits appear in the anodes, replace them.  
Q. How often should the anodes be inspected?  
A. Approximately every six months.  
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S U F  
S E R V I C E  
E R R O R  
H A N D B O O K  
C O D E S  
ERROR CODES  
CODE INDICATION  
00 This is normal operation, 00 is displayed each time the heater is powered up.  
Indicates the pressure switch circuit was not open during the prediagnostic system  
check when the proper state of the Draft Prover Switches are verified. The Blower  
Prover Switch is normally open, the circuit should therefore be open during the  
prediagnostic system check at the beginning of each cycle. Check Blower Proving  
01  
Switch for continuity with the blower off, there should be no continuity, check  
pressure switch wiring.  
02 Indicates the heater failed to light after 3 trials. Check ignitor, gas pressure.  
Indicates the ECO is open. Check water temperature in tank, ECO will open at 202°  
F and can be reset below 160° F.  
04  
Indicates a Temperature Probe is open. Check both probes for proper resistance  
and continuity.  
05  
Indicates the Pressure Switch Circuit did not close after blower was energized.  
Check normally open Blower Prover Switch operation, check normally closed  
11 Blocked Outlet, Inlet, and Low Gas pressure (SUF 240 only) to ensure they remain  
closed. Check for blocked vent pipe (s) or if equivalent feet venting limits have been  
exceeded.  
Indicates temperature sensed by probe(s) is out of bounds, reading is less than  
30° F. Check resistance of temp probes, check water temperature in tank.  
15  
Indicates Ignition Relay failure. Should be off and it is on. Try resetting, turn power  
off and on, if code remains, replace board.  
22  
Indicates temperature sensed by probe(s) is out of bounds. Reading is more than  
220° F. Check resistance of temp probes, check water temperature.  
25  
Internal software or hardware errors, electrical line noise can cause erratic  
CODE #S  
ABOVE  
199  
operation and these error codes. Try adding a “line filter” (available from electrical  
suppliers) to the 120 VAC power supply. If these errors codes persist or the control  
cannot be reset, replace the control board.  
All these errors cause a “soft” lockout with the exception of 04 -  
ECO, which is a “hard” lockout. Soft lockouts will reset automati-  
cally after 60 minutes or if the reset button is pushed at any time.  
The ECO lockout, error code 04 will have to be manually reset by  
pushing the rest button after water in the tank has cooled below  
160° F.  
State Water Heaters  
Ashland City, Tennessee © 2004  
Technical Training Department  
STC-077  
39  
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S U F  
S E R V I C E  
H A N D B O O K  
S E R V I C E  
C H E C K L I S T  
SERVICE CHECKLIST  
This is not intended to be and all-inclusive list of the problem that the Service Agent may encounter. Any item checked “no” on  
this list should be thoroughly investigated and corrective action taken, if required.  
SERVICE AGENT:  
MODEL NUMBER:  
SERIAL NUMBER:  
INSTALLATION DATE:  
SERVICE DATE:  
LOCATION ADDRESS:  
PHONE  
(
)
-
GAS  
TYPE — CHECK ONE  
NATURAL  
PROPANE  
YES  
NO  
PROPER GAS VALUE VERIFIED  
CHECK CLEARANCE (CIRCLE ANSWER)  
I.  
A.  
B.  
Are exterior clearances adequate?  
Are interior clearances adequate?  
Comments:  
yes  
yes  
no  
no  
II.  
CHECK MAKEUP AIR REQUIREMENTS  
A.  
Is the quality of make-up air adequate?  
Comments:  
yes  
yes  
no  
no  
B.  
Is the quantity of make-up air adequate?  
Comments:  
III.  
GAS PRESSURE (FILL IN BLANK) — ALL UNITS ON.  
A.  
B.  
Supply gas pressure __ inches of W.C. (flowing)  
Manifold gas pressure (main burner) __ inches of W.C. (flowing)  
Comments:  
IV. VENTING (CHECK)  
A.  
B.  
Acceptable equivalent footage  
Proper material  
yes  
yes  
yes  
yes  
no  
no  
no  
no  
C. Proper exterior installation  
D. Condensate will drain  
Comments:  
V. WATER PIPING  
Is the system properly sized?  
Is the system properly installed?  
Are there any water leaks?  
Does the installation have a recirculating system?  
If so, is it operational?  
yes  
yes  
yes  
yes  
yes  
no  
no  
no  
no  
no  
VI. SAFETY  
A.  
Air  
yes  
yes  
no  
no  
If exhaust is blocked will unit lockout?  
If air intake is blocked will unit lockout?  
B.  
Water Temperature  
- Is the thermostat adjusted to the lowest acceptable temperature?  
- Does the installation have a mixing valve?  
yes  
yes  
yes  
yes  
no  
no  
no  
no  
- If so, is it operational?  
- What is the outlet temperature of the mixing valve?  
NOTE: To minimize the risk of scalding, the manufacturer recommends storing water at 120° F.  
Is a properly rated temperature and pressure relief valve installed?  
yes  
yes  
yes  
no  
no  
no  
Is there a properly installed expansion tank?  
Should there be?  
C. Electrical  
Is the 120 VAC electrical powers supply properly wired? (including polarity)  
Are all the SUF control covers in place?  
Is the 120 VAC electrical power supply properly fused?  
D. Flammables  
yes  
yes  
yes  
no  
no  
no  
Are flammable materials located in the area of the water heater? or air intake?  
Are flammable vapors located in the area of the water heater? or air intake?  
Gas  
yes  
yes  
no  
no  
E.  
If the gas supply is reduced or turned off will the unit turn off?  
Comments:  
yes  
no  
[This service checklist may be photo copied to assist with SUF service calls.]  
Technical Training Department  
STC-077  
State Water Heaters  
Ashland City, Tennessee © 2004  
40  
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970 & 973 Series  
STC-077  
S U F  
S E R V I C E  
P A R T S  
H A N D B O O K  
L I S T  
SUF SERVICE HANDBOOK  
PARTS LIST  
SUF MODELS 100 – 150, 100 – 199 AND 100 – 240  
STATE WATER HEATERS  
500 LINDHAL PARKWAY, ASHLAND CITY, TN 37015  
PHONE: 1-800-821-2017 • FAX 1-800-644-9306  
WWW.STATEWATERHEATERS.COM  
State Water Heaters  
Ashland City, Tennessee © 2004  
Technical Training Department  
STC-077  
41  
Download from Www.Somanuals.com. All Manuals Search And Download.  
S U F  
S E R V I C E  
P A R T S  
H A N D B O O K  
L I S T  
ULTRA FORCE SUF MODELS REPLACEMENT PARTS  
SUF  
100 150  
SUF  
100 199  
SUF  
100 240  
SUF  
100 150-LP  
SUF  
100 199-LP  
ITEM DESCRIPTION  
1 Anode  
43817-53  
181863  
193354  
192622-0  
194114-1  
192696  
192806  
191794-1  
191746-72  
193202  
192473  
192815  
192478  
192641-1  
99038  
43817-53  
181863  
193354  
192622-0  
194114  
192696  
192806  
191794-1  
191746-72  
193202  
192473  
192815  
192478  
192641-1  
99038  
43817-53  
181863  
193203  
192622-0  
194114-2  
192696  
192806  
191794-1  
191746-72  
193281  
192473  
192815  
192478  
192886-1  
99038  
43817-53  
181863  
193354  
192622-0  
194114-5  
192696  
192806  
191794-1  
191746-72  
193202  
192473  
192815  
192478  
192886-1  
99038  
43817-53  
181863  
193354  
192622-0  
194114-4  
1926964  
192806  
191794-1  
191746-72  
193202  
192473  
192815  
192478  
192886-1  
99038  
2 *Barb,Hose  
3 Blower  
4 Board,Display Panel  
5 Burner Assembly  
6 Clamp, 3  
7 Clamp, Hose  
8 Clamp,Hose,Nylon  
9 Condensate Hose  
10 *Direct Vent Kit  
11 Elbow, 90 Degree  
12 Exhaust Terminal  
13 Flame Rod Assembly  
14 Flange, Inlet  
15 Gasket, C.O  
16 Igniter Assembly  
17 *Instruction Manual  
18 Intake Terminal  
19 Orifice, Gas  
192638  
195723  
182167  
192477-1  
195721  
99037  
192638  
195723  
182167  
192477  
195721  
99037  
192638  
195723  
181762  
192477-2  
195721  
99037  
192638  
195723  
182167  
192477-5  
195721  
99037  
192638  
195723  
182167  
192477-4  
195721  
99037  
20 Panel,Front  
21 Plate, C.O  
22 *Screen, Exhaust  
23 Press. Switch, Low Gas  
24 Tube, Air  
181662  
- - - - -  
181662  
- - - - -  
181662  
191149-1  
192469-10  
26273-4  
192454  
192467  
192331  
195731  
181662  
- - - - -  
181662  
- - - - -  
192469-10  
26273-4  
192797  
192467  
192331  
195731  
192469-10  
26273-4  
192797  
192467  
192331  
195731  
192469-10  
26273-4  
192454-1  
192467  
192331  
195731  
192469-10  
26273-4  
192454-1  
192467  
192331  
195731  
25 Valve, Drain  
26 Valve, Gas  
27 Valve, Relief  
28 Gasket, Burner  
29 Metal Cage Assy  
Shaded parts are recommended stock items for emergency replacement. Consider gas used in your area only.  
*Not illustrated.  
Technical Training Department  
STC-077  
State Water Heaters  
Ashland City, Tennessee © 2004  
42  
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S U F  
S E R V I C E  
P A R T S  
H A N D B O O K  
L I S T  
ULTRA FORCE SUF CONTROLS PARTS LIST  
SUF  
100 150  
SUF  
100 199  
SUF  
100 240  
SUF  
100 150-LP  
SUF  
100 199-LP  
ITEM DESCRIPTION  
1 Blocked Inlet Switch  
2 Blocked Outlet Proving Switch  
3 Blower Proving Switch  
6 Cable to Control  
193355  
193362  
193295  
192623  
193822  
192622  
196597  
196598  
193243  
192608-1  
192152  
192024-3  
192024-8  
193363  
193364  
193295  
192623  
193822  
192622  
196597  
196598  
193243  
192608-1  
192152  
192024-3  
192024-8  
193361  
193357  
193295  
192623  
193822  
192622  
196597  
196598  
193243  
192608-1  
192152  
192024-3  
192024-8  
193355  
193357  
193295  
192623  
193822  
192622  
196597  
196598  
193243  
192608-1  
192152  
192024-3  
192024-8  
193356  
193357  
193295  
192623  
193822  
192622  
196597  
196598  
193243  
192608-1  
192152  
192024-3  
192024-8  
7 Control Board  
8 Display Board  
9 E.C.O./Upper Probe  
10 Lower Temperature Probe  
12 Switch-On/Off  
13 Transformer  
14 Tubing, Connector  
15 Tubing, Pressure  
16 Tubing, Pressure  
Shaded parts are recommended stock items for emergency replacement. Consider gas used in your area only.  
State Water Heaters  
Ashland City, Tennessee © 2004  
Technical Training Department  
STC-077  
43  
Download from Www.Somanuals.com. All Manuals Search And Download.  
S U F  
S E R V I C E  
P A R T S  
H A N D B O O K  
L I S T  
N O T E S :  
Technical Training Department  
STC-077  
State Water Heaters  
Ashland City, Tennessee © 2004  
44  
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