State Water Heaters Utra-Force STC-077 How to use

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SUF Service Handbook
TABLE OF CONTENTS
STC-077
Introduction . . . . . . . . . . . . . . . . . . . 2
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
Operation
Sequence of Operation . . . . . . . . . . 15
Controls . . . . . . . . . . . . . . . . . . . . . . 16
Circuit Boards. . . . . . . . . . . . . . . . . . 17
Troubleshooting
Pre-Service. . . . . . . . . . . . . . . . . . . . 18
120 VAC to Control. . . . . . . . . . . . . . 18
Transformer . . . . . . . . . . . . . . . 19 – 20
ECO Check . . . . . . . . . . . . . . . 21 – 22
Temperature Probe. . . . . . . . . . . . . . 23
Pressure Switch Continuity . . . . . . . 24
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
Component Information
Orifice Tables . . . . . . . . . . . . . . . . . . 32
Pressure Switches . . . . . . . . . . 33 – 34
Wiring Diagrams . . . . . . . . . . . . . . 35
Service Aids . . . . . . . . . . . . . . . . . . 36
SUF Muffler . . . . . . . . . . . . . . . . . . . 37
Questions & Answers . . . . . . . . . . 38
Error Codes. . . . . . . . . . . . . . . . . . . 39
Service Checklist . . . . . . . . . . . . . . 40
Parts Lists
Models 100 – 150, 100 – 199,
and 100 – 240 . . . . . . . . . . . 41 – 43

SUF SERVICE HANDBOOK
INTRODUCTION
Technical Training Department State Water Heaters
STC-077 2Ashland City, Tennessee © 2004
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)
•1/2”, 1” and 11/8” 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.

SUF SERVICE HANDBOOK
INSTALLATION
State Water Heaters Technical Training Department
Ashland City, Tennessee © 2004 3 STC-077
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
NOTE: 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.
GAS SUPPLY SPECIFICATIONS SUF 240 SUF 150 & 199 SUF 150 & 199
NATURAL GAS NATURAL GAS PROPANE GAS
Max. Gas Supply Pressure Inches W.C. 12.0 (3 kPa) 12.0 (3 kPa) 14.0 (3.45 kPa)
Nominal Gas Supply Pressure Inches W.C. 7.0 (1.75 kPa) 7.0 (1.75 kPa) 11.0 (2.74 kPa)
Minimal Gas Supply Pressure Inches W.C. 5.5 (1.37 kPa) 4.5 (1.12 kPa) 11.0 (2.74 kPa)
Manifold Pressure Inches W.C. 4.0 (1 kPa) 3.5 (0.8 kPa) 10.0 (2.5 kPa)
REGULATED GAS SUPPLY LINE
MAIN GAS
SHUTOFF VALVE
DIRT LEG TEE
PIPE CAP
PRESSURE REGULATOR
ADJUSTMENT
(COVER SCREW)
INLET PRESSURE
TAP
GAS INLET
GAS VALVE ON/OFF
TH & TR TERMINALS
(MAIN VALVE)
MANIFOLD
PRESSURE TAP
GAS OUTLET

SUF SERVICE HANDBOOK
INSTALLATION
Technical Training Department State Water Heaters
STC-077 4Ashland City, Tennessee © 2004
VENTING
Equivalent Feet of Pipe Intake or Exhaust
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.
VENT LENGTH TABLE
NUMBER OF 90°
ELBOWS 3” MINIMUM PIPE (FEET) 3” MAXIMUM PIPE (FEET) 4” MAXIMUM PIPE (FEET)
ONE (1) 745115
TWO (2) 7 40 110
THREE (3) 7 35 105
FOUR (4) 7 30 100
FIVE (5) 7 -- 95
SIX (6) 7 -- 90
3” (7.6CM) 45° PVC ELBOW WITH MESH SCREEN
WARNING WHENTHEUNITISTO
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.

SUF SERVICE HANDBOOK
INSTALLATION
State Water Heaters Technical Training Department
Ashland City, Tennessee © 2004 5 STC-077
VENTING CONFIGURATIONS
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.
SEALED DIRECT
VENT VERTICAL SEALED DIRECT
VENT SIDEWALL INDOOR CONVENTIONAL
VERTICAL INDOOR CONVENTIONAL
SIDEWALL
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

SUF SERVICE HANDBOOK
INSTALLATION
Technical Training Department State Water Heaters
STC-077 6Ashland City, Tennessee © 2004
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
Dimension 211/8in. may be lengthened to 60 in. maximum. Dimension 211/8in. may also be short-
ened by cutting the pipes, provided in the kit, to 12 in. minimum. Dimension 39 will change accord-
ingly as dimension 211/8in. is lengthened or shortened
Vertical Installation
Horizontal
Installation

SUF SERVICE HANDBOOK
INSTALLATION
State Water Heaters Technical Training Department
Ashland City, Tennessee © 2004 7 STC-077
VENTING CLEARANCES
This illustrates the exterior clearances for these SUF units when installed as direct vent heaters.
NOTE: 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

SUF SERVICE HANDBOOK
INSTALLATION
Technical Training Department State Water Heaters
STC-077 8Ashland City, Tennessee © 2004
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.

SUF SERVICE HANDBOOK
INSTALLATION
State Water Heaters Technical Training Department
Ashland City, Tennessee © 2004 9 STC-077
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.

SUF SERVICE HANDBOOK
INSTALLATION
Technical Training Department State Water Heaters
STC-077 10 Ashland City, Tennessee © 2004
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.

SUF SERVICE HANDBOOK
INSTALLATION
State Water Heaters Technical Training Department
Ashland City, Tennessee © 2004 11 STC-077
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.

SUF SERVICE HANDBOOK
INSTALLATION
Technical Training Department State Water Heaters
STC-077 12 Ashland City, Tennessee © 2004
CONTAMINATED AIR
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.
=RUST
CHIPS

SUF SERVICE HANDBOOK
INSTALLATION
State Water Heaters Technical Training Department
Ashland City, Tennessee © 2004 13 STC-077
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

SUF SERVICE HANDBOOK
INSTALLATION
Technical Training Department State Water Heaters
STC-077 14 Ashland City, Tennessee © 2004
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“CorrosionResistanceof 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.

SUF SERVICE HANDBOOK
OPERATION
State Water Heaters Technical Training Department
Ashland City, Tennessee © 2004 15 STC-077
OPERATION
SEQUENCE OF OPERATION

SUF SERVICE HANDBOOK
OPERATION
Technical Training Department State Water Heaters
STC-077 16 Ashland City, Tennessee © 2004
CONTROLS
NORMAL INDICATIONS / READINGS / SETTINGS
During Call for Heat
• On/Off switch in the “on” position
• 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
DISPLAY PANEL (CONTROL PANEL)
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.

SUF SERVICE HANDBOOK
OPERATION
State Water Heaters Technical Training Department
Ashland City, Tennessee © 2004 17 STC-077
CIRCUT BOARDS
DISPLAY CIRCUIT BOARD
IGNITION CIRCUIT BOARD

SUF SERVICE HANDBOOK
TROUBLESHOOTING
Technical Training Department State Water Heaters
STC-077 18 Ashland City, Tennessee © 2004
TROUBLESHOOTING
PRE-SERVICE TIPS
SUF SERVICE HANDBOOK
120 VAC TO CONTROL
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.
STEP 1 120 VAC TO CONTROL BOARD
IF… THEN
120 VAC is not present check On/Off switch, turn switch on, replace On/Off switch if defective, restore
power to the water heater.
120 VAC is present reconnect CN1 plug, continue to Step 2.
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
STC-077

SUF SERVICE HANDBOOK
TROUBLESHOOTING
State Water Heaters Technical Training Department
Ashland City, Tennessee © 2004 19 STC-077
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.
STEP 2 120 VAC TO TRANSFORMER
IF… THEN
120 VAC is not present check CN1 plug connection
replace control board if Step 1 has been performed and results were successful.
120 VAC is present reconnect CN4 plug to control board, continue to Step 3.