HTP UFT-100W Guide

120 Braley Rd. P.O. Box 429 East Freetown, MA 02717-0429 www.htproducts.com
LP-543 REV. 12.15.15
Universal Fire Tube Boiler
Wall Mount Models
USER’S INFORMATION
MANUAL
Models
UFT-80W / 100W / 120W / 140W / 175W / 199W
Heat Exchanger Bears the ASME “H” Stamp
NOTICE: HTP reserves the right to make product changes or updates without notice and will not be held liable for typographical errors
in literature.
NOTE TO CONSUMER: PLEASE KEEP ALL INSTRUCTIONS FOR FUTURE REFERENCE.
IF THE INFORMATION IN THIS MANUAL IS NOT FOLLOWED EXACTLY, A FIRE OR EXPLOSION MAY RESULT, CAUSING
PROPERTY DAMAGE, PERSONAL INJURY, OR LOSS OF LIFE. DO NOT STORE GASOLINE OR OTHER FLAMMABLE VAPORS
AND LIQUIDS IN THE VICINITY OF THIS OR ANY OTHER BOILER.
WHAT TO DO IF YOU SMELL GAS
Do not try to light any boiler.
Do not touch any electrical switch.
Do not use any phone in your building.
Immediately call your gas supplier from a neighbor’s phone. Follow the gas supplier’s instructions.
If you cannot reach your gas supplier, call the fire department. Installation and service must be provided by a qualified installer,
service agency, or the gas supplier.

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LP-543 Rev. 12.15.15
The following defined terms are used throughout this manual to bring attention to the presence of hazards of various risk
levels, or to important product information.
DANGER indicates an imminently hazardous situation which, if not avoided, will result in death or serious injury.
WARNING indicates a potentially hazardous situation which, if not avoided, could result in death or serious injury.
CAUTION indicates a potentially hazardous situation which, if not avoided, may result in minor or moderate injury.
CAUTION used without the safety alert symbol indicates a potentially hazardous situation which, if not avoided, may result in property
damage.
NOTICE
SAFETY INSTRUCTIONS
NOTICE is used to address practices not related to personal
injury.
SAFETY INSTRUCTIONS (or equivalent) signs indicate specific
safety related instructions or procedures.
NOTE: Contains additional information important to a procedure.

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LP-543 Rev. 12.15.15
TABLE OF CONTENTS
PART 1 –PRODUCT AND SAFETY INFORMATION...............................................................................................................................4
A. BEFORE OPERATION......................................................................................................................................................................4
B. DURING OPERATION.......................................................................................................................................................................5
C. TROUBLESHOOTING AND GENERAL CAUTIONARY STATEMENTS...........................................................................................5
PART 2 –MAINTENANCE ........................................................................................................................................................................6
A. SERVICE TECHNICIAN ....................................................................................................................................................................6
B. OWNER MAINTENANCE ..................................................................................................................................................................7
PART 3 –MAINTENANCE PROCEDURES..............................................................................................................................................7
A. DAILY MAINTENANCE –TO BE PERFORMED BY OWNER...........................................................................................................7
B. MONTHLY MAINTENANCE –TO BE PERFORMED BY OWNER....................................................................................................8
C. 6 MONTH MAINTENANCE –TO BE PERFORMED BY OWNER.....................................................................................................8
D. ANNUAL MAINTENANCE –ONLY TO BE PERFORMED BY A QUALIFIED SERVICE TECHNICIAN............................................9
PART 4 –TROUBLESHOOTING ..............................................................................................................................................................9
MAINTENANCE NOTES ..................................................................................................................................................................10

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LP-543 Rev. 12.15.15
PART 1 –PRODUCT AND SAFETY INFORMATION
USER –Have this boiler serviced/inspected by a qualified service technician annually.
TO TURN OFF GAS TO THE BOILER
1. Set the thermostat to the lowest setting.
2. Turn off all electrical power to the boiler.
3. Turn manual gas shutoff valve to “OFF”.
Proper care of this boiler is the user’s / owner’s responsibility. The user / owner should carefully read and understand the Operating
Information in this manual before operating this boiler.
It is the user / owner’s responsibility to know the location of the gas shut-off valve and how to operate it. Immediately close the gas
shut-off valve if the boiler is subjected to fire, overheating, flood, physical damage, or any other damaging condition that might affect the
operation of the unit. Have the boiler checked by a qualified technician before resuming operation.
DO NOT use this boiler if ANY part has been under water. Immediately call a qualified technician to inspect the boiler and replace any
part of the control system or gas control which has been under water.
DO NOT power up the boiler unless the gas and water supply valves are fully opened. Make sure the fresh air intake pipe and exhaust
vents are open and functional.
DO NOT attempt to install, repair, or service this boiler. Contact a qualified technician if the boiler needs repair or maintenance. Ask
your gas supplier for a list of qualified service providers.
DO NOT use spray paint, hair spray, or any other flammable sprays near the boiler or near the exterior fresh air intake pipe termination.
DO NOT place any items in or around the exterior exhaust vent termination and/or fresh air intake pipe that could restrict or block the
flow in or out of the vent system.
All safety devices must be tested by the installer / service technician after the boiler is installed.
Always verify proper boiler operation with the service technician after servicing.
The gas ignition system components must be protected from water (dripping, spraying, rain, etc.) during boiler operation and service
(circulator replacement, condensate trap, control replacement, etc.)
The Er:80 code will display when there is no water in the boiler. Ensure the boiler is full of water and all air has been purged from the
system. Then manually reset the boiler to resume operation. If the Er:80 code displays again, call a qualified service technician to
inspect the boiler.
This boiler features a factory installed overheating prevention device. This limit provides boiler shutdown in the event that the boiler
water temperature exceeds the set point of the limit control. Certain local codes require additional water temperature limiting devices.
FAILURE TO ADHERE TO THE GUIDELINES IN THIS MANUAL CAN RESULT IN SUBSTANTIAL PROPERTY DAMAGE, SEVERE
PERSONAL INJURY, OR DEATH.
A. BEFORE OPERATION
1. Check the Gas Type (NG/LP)
When operating the boiler for the first time, ensure the connected gas type matches that of the gas type of the boiler. Check
whether the gas supplied is NG or LP. The boiler gas type is indicated on the rating plate on the side of the boiler.
Attempting to operate this boiler on a gas supply other than specified on the rating plate will result in improper boiler operation, and
could result in property damage or personal injury.
2. Check the Power (120V 60Hz)
Ensure the boiler is connected to a properly rated power supply.
3. Check the Automatic Feed Valve
Ensure the automatic feed valve to the boiler is providing the proper pressure to the central heating (CH) loop.
4. Check the Gas Shut-Off Valve
Ensure the manual gas shut-off valve is open. The boiler will not operate unless it is supplied with gas.
5. Check the Area around the Boiler
Remove any combustible or flammable materials from the area around the boiler and do not hang anything from the exhaust
vent pipe.
Do not operate the boiler if its combustion air intake is located in or near one of the areas or in the vicinity of products listed in Table 1.
These areas will always contain hazardous contaminates that can form strong acids while passing through the burner and vent system.
These acids will corrode the boiler’s heat exchanger, burner components and vent system, resulting in flue gas spillage and/or water
leakage, possible substantial property damage, severe personal injury, or death. If the boiler combustion air intake is located in any
area likely to cause or contain contamination, or if products which would contaminate the air cannot be removed, the intake must be re-
piped and terminated to another location.
DO NOT re-pipe the combustion ventilation system on your own. Call a qualified service provider for assistance.

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LP-543 Rev. 12.15.15
PRODUCTS TO AVOID
AREAS LIKELY TO HAVE CONTAMINANTS
Spray cans containing fluorocarbons
Dry cleaning/laundry areas and establishments
Permanent wave solutions
Swimming pools
Chlorinated waxes/cleaners
Metal fabrication plants
Chlorine-based swimming pool chemicals
Beauty shops
Calcium chloride used for thawing
Refrigeration repair shops
Sodium chloride used for water softening
Photo processing plants
Refrigerant leaks
Auto body shops
Paint or varnish removers
Plastic manufacturing plants
Hydrochloric or Muriatic acid
Furniture refinishing areas and establishments
Cements and glues
New building construction
Antistatic fabric softeners used in clothes dryers
Remodeling areas
Chlorine-type bleaches, laundry detergents, and cleaning solvents
Garages and workshops
Adhesives used to fasten building products
Table 1
B. DURING OPERATION
1. Check for Gas Leaks
Frequently check the gas pipe and connections for leaks with a soapy solution. If air bubbles appear during the test, gas is
leaking. Close the gas supply valve and call your gas supplier for inspection.
After any repair of the gas pipeline or replacement of the gas regulator, call a qualified service technician to observe the installation and
replacement before restoring power to the boiler. Failure to do so could result in a fire or explosion, substantial property damage,
severe personal injury, or death.
2. Check Exhaust Vent and Intake Pipe for Proper Ventilation
Ensure there is sufficient ventilation while operating the boiler.
Improper ventilation could result in premature boiler failure. Such
failures ARE NOT covered by boiler warranty.
Exhaust gas entering the living space can cause carbon monoxide
poisoning. If exhaust gas should leak into the living space:
Shut down the boiler.
Close the gas valve.
Open windows for ventilation.
Ensure that the CO detectors are operating properly.
Immediately call a qualified service technician to inspect the boiler and
exhaust vent pipe. Any damages to the exhaust vent pipe should be
repaired immediately. Failure to do so could result in substantial property
damage, severe personal injury, or death.
3. Burn Warning
Take caution when inspecting the boiler and its internal
components, exhaust vent, and/or water pipes. These components can get extremely hot during boiler operation.
4. Combustibles and Flammable Material Warning
Do not store combustibles or flammable materials in the vicinity of this boiler. Do not hang anything from the exhaust pipe.
Storing flammable or combustible materials near this boiler could result in a fire or explosion, substantial property damage, severe
personal injury, or death.
5. Check for Water Leaks
Do not attempt to clean the heating system. Call a qualified service technician for service.
If you notice any leaks, immediately call a qualified service technician. Leaks in boiler or piping must be repaired at once.
C. TROUBLESHOOTING AND GENERAL CAUTIONARY STATEMENTS
DO NOT use this boiler for any purposes other than those specifically described by HTP, Inc (to provide central heating and domestic
hot water). Using this boiler for unapproved purposes WILL VOID the warranty, and could result in property damage, serious personal
injury, or death.

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LP-543 Rev. 12.15.15
Ensure each zone valve connected to the boiler is open while the boiler is operating. Doing so ensures proper heating system
operation.
DO NOT wipe the boiler or control panel with a wet cloth. Doing so may result in an electric shock, substantial property damage,
premature boiler failure, severe personal injury, or death.
Hydronic systems that use glycol as heat transfer fluid must be serviced periodically. Glycol can break down over time, become acidic,
and attack gaskets and seals in boilers. This can result in property damage, severe personal injury, or death.
Each glycol manufacturer has different recommendations for testing and replacement. Do not test glycol quality yourself. Have your
qualified service technician check glycol quality during annual servicing. If you are unsure when your glycol was last tested, call a
qualified service technician to test and replace glycol, if necessary.
If the boiler is not to be used for an extended period of time during freezing conditions, consider shutting down the system and draining
it of water. Shut off the gas and cold water supply valves.
DO NOT attempt to disassemble this boiler. Doing so could result in improper boiler operation or premature boiler failure, substantial
property damage, and/or severe personal injury or death due to electric shock, fire, or explosion. If repairs are required, contact a
qualified service technician.
DO NOT touch the exhaust vent pipe. Doing so could result in substantial personal injury.
APPROXIMATE TIME / TEMPERATURE RELATIONSHIPS IN SCALDS
Be careful when opening a hot water faucet or draining
water from the boiler. Water temperature over 125oF can
instantly cause severe burns, or death, from scalds.
Children, disabled, and elderly are at the highest risk of
being scalded. See instruction manual before setting
temperature at boiler. Feel water before bathing or
showering!
120oF
More than 5 minutes
125oF
1 ½ to 2 minutes
130oF
About 30 seconds
135oF
About 10 seconds
140oF
Less than 5 seconds
145oF
Less than 3 seconds
150oF
About 1 ½ seconds
155oF
About 1 second
PART 2 –MAINTENANCE
A. SERVICE TECHNICIAN
The following maintenance should be performed by a qualified service technician annually:
General
Attend to any reported problems.
Inspect the interior of the boiler cabinet area; clean and vacuum if necessary.
Clean the condensate trap and fill with fresh water.
If applicable, check the condensate neutralizer and ensure it is full of condensate neutralizing marble chips.
Check for leaks: Water, gas, flue and condensate.
Verify exhaust vent and intake piping are in good condition and sealed tight.
Check exhaust vent and intake pipe bracing. Ensure bracing is undamaged and in good condition.
Check boiler water pressure, piping and expansion tank.
Check control settings.
Check ignition electrode. Sand off any white oxide. Clean and reposition.
Check ignition and ground wiring.
Check all control wiring and connections.

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LP-543 Rev. 12.15.15
Check burner flame pattern (stable and uniform).
Additional Items if Combustion or Performance is Poor
Clean heat exchanger and flue ways.
Remove burner assembly and clean burner head using compressed air only.
Once the maintenance items are completed, the service technician should review service with the owner.
B. OWNER MAINTENANCE
Periodically
Check area around the boiler.
Check and remove any blockage from the outdoor exhaust vent and intake pipe terminations. DO NOT perform this
maintenance if exhaust vent and intake pipe terminations are in difficult to reach locations.
Check the CH loop pressure gauge. Normal CH pressure will range from 15 –30 psi.
Monthly
Check exhaust vent and intake piping.
Check exhaust vent and intake pipe bracing. Ensure bracing is undamaged and in good condition.
Check the pressure relief valve.
Check the condensate drain system.
If applicable, check the condensate neutralizer and ensure it is full of condensate neutralizing marble chips.
Every 6 Months
Check boiler piping and gas supply piping for corrosion or signs of potential leakage.
PART 3 –MAINTENANCE PROCEDURES
The boiler must be inspected and serviced annually, preferably at the start of the heating season, by a qualified service technician. In
addition, the maintenance and care of the boiler as outlined in this manual must be performed by the user/owner to assure maximum
efficiency and reliability. Follow the maintenance procedures given throughout this manual. Failure to perform the service and
maintenance or follow the directions in this manual could damage the boiler or system components, resulting in substantial property
damage, severe personal injury, or death.
A. DAILY MAINTENANCE –TO BE PERFORMED BY OWNER
Check the Surrounding Area
To prevent the potential of substantial property damage, severe personal injury, or death, eliminate all the materials listed in Table 1
from the area surrounding the boiler and the vicinity of the combustion air intake. If contaminates are found:
Remove products immediately from area.
If contaminates have been there for an extended period, call a qualified service technician to inspect the boiler for possible
damage from acid corrosion.
If products cannot be removed, immediately call a qualified service technician to re-pipe the combustion air intake piping away from the
contaminated areas.
Combustible/Flammable Materials
Do not store combustible materials, gasoline, or other flammable vapors or liquids near the boiler. If found, remove these materials
immediately.
Air Contaminates
If allowed to contaminate combustion air, products containing chlorine or fluorine will produce acidic condensate that will cause
significant damage to the boiler. Read the list of potential contaminates and areas likely to have these contaminates in Table 1. If any of
these contaminates are in the room where the boiler is located, or combustion air is taken from one of the areas listed, the
contaminates must be removed immediately or the intake pipe must be relocated to another area.
Ensure the Boiler Cabinet is Closed
Ensure the boiler cabinet is closed. Tighten the upper screw to secure it. The cabinet must be closed while the boiler is running.
Check the Power Source
Make sure the power cord is properly connected. The main power line is connected to the manual switch box inside the boiler.

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LP-543 Rev. 12.15.15
Check the Status of the Control Panel
Observe the Control Panel to ensure the boiler is powered on, and to check for any error codes. Clear any debris from the panel.
Check Exhaust Vent and Intake Pipe Terminations
Verify that the boiler exhaust vent and intake pipe terminations are clean and free of obstructions. Remove any debris from the exhaust
vent or intake pipe openings. If removing the debris does not allow the boiler to operate correctly, contact your qualified service
technician to inspect the boiler and the vent system.
Check Pressure Gauges
Check the CH loop pressure gauge.
Normal CH pressure will range from 15 –30 psi.
Boiler will not operate if pressure is lower than 15 psi.
Higher pressure readings may indicate a problem with the expansion tank.
Contact a qualified service technician if pressures are low or high, or there is an issue with boiler operation.
B. MONTHLY MAINTENANCE –TO BE PERFORMED BY OWNER
Check Exhaust Vent and Intake Piping
Visually inspect the exhaust vent for any signs of blockage, leakage, or deterioration of the piping. Inspect the exhaust vent bracing.
Ensure bracing is undamaged and in good condition. Notify a qualified service technician immediately if any problems are found.
Failure to inspect the venting system and have it repaired by a qualified service technician can result in vent system failure, causing
severe personal injury or death.
Visually inspect the intake piping for any signs of blockage. Inspect the entire length of the intake pipe to ensure piping is intact and all
joints are properly sealed. Inspect the intake pipe bracing. Ensure bracing is undamaged and in good condition. Notify a qualified
service technician if any problems are found.
Check Pressure Relief Valves
Visually inspect the primary pressure relief valves and discharge pipes for signs of weeping or leakage.
If pressure relief valves often weep, the expansion tank may not be operating properly. Immediately contact a qualified service
technician to inspect the boiler and system.
Check Vent Condensate Drain System
While the boiler is running, check the discharge end of the condensate drain tubing. Ensure no flue gas is leaking from the
condensate drain tubing by holding your fingers near the opening.
If you notice flue gas leaking from the opening, this indicates a dry condensate drain trap. If problem persists, contact a
qualified service technician to inspect the boiler and condensate line and refill the condensate trap.
If applicable, check the condensate neutralizer and ensure it is full of condensate neutralizing marble chips.
C. 6 MONTH MAINTENANCE –TO BE PERFORMED BY OWNER
Check Primary and Gas Piping
Remove the boiler cover and perform a gas leak inspection following Operating Instructions, page 2, this manual. If gas odor
or leak is detected, follow procedures on page 2. Call a qualified service technician.
Visually inspect for leaks around the internal boiler water connections and around the heat exchanger. Visually inspect the
external system piping, circulators, and system components and fittings. Immediately call a qualified service technician to
repair any leaks.
Have leaks fixed at once by a qualified service technician. Failure to comply could result in substantial property damage, severe
personal injury, or death.
Operate Pressure Relief Valves
Before proceeding, verify that the relief valve outlets have been piped to a safe place of discharge, avoiding any possibility of
scalding from hot water.
To avoid water damage or scalding due to relief valve operation, a discharge line must be connected to the valve outlet and directed to
a safe place of disposal. This discharge line must be installed by a qualified service technician or heating/plumbing installer in
accordance with the boiler installation manual. The discharge line must be terminated so as to eliminate possibility of severe burns or
property damage should the valve discharge.

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LP-543 Rev. 12.15.15
Read the pressure gauges to ensure the system is pressurized. Check the CH loop pressure gauge. Normal CH pressure will
range from 15 –30 psi. Boiler will not operate if pressure is lower than 15 psi.
Lift the relief valve top lever slightly, allowing water to relieve through the valve and discharge piping.
If water flows freely, release the lever on the pressure relief valve and allow the valve to seat. Watch the end of the relief valve
discharge pipe to ensure that the valve does not weep after the line has had time to drain. If the valve weeps, lift the lever
again to attempt to clean the valve seat. If the valve does not properly seat and continues to weep, contact a qualified service
technician to inspect the valve and system.
Repeat the process on the other valve.
If water does not flow from the valve when you completely lift the lever, the valve or discharge line may be blocked.
Immediately shut the boiler down per instructions on page 2 and call a qualified service technician to inspect the valve and
system.
D. ANNUAL MAINTENANCE –ONLY TO BE PERFORMED BY A QUALIFIED SERVICE TECHNICIAN
Flushing the Boiler
Flushing the boiler heat exchanger and CH loop is a complicated procedure that should only be performed by a qualified service
technician.
NOTE: Improper maintenance WILL VOID boiler warranty.
PART 4 –TROUBLESHOOTING
To save time and money, review the following initial diagnostic steps before calling for service.
TROUBLESHOOTING CHART
PROBLEM
POSSIBLE CAUSES
POSSIBLE REMEDIES
No electrical power
to the boiler
1. Is the plug on the power supply cord unplugged
from the electrical outlet?
2. Is electrical panel’s 10 Amp circuit breaker tripped?
3. Is the fuse on the circuit board good?
4. Is there a power outage to the home?
1. Reset the plug.
2. Reset the circuit breaker.
3. If the display panel is blank, unplug the unit or
contact an authorized service technician.
4. Contact the power company.
A fan can be heard
even when the unit is
not operating.
1. The fan continues to operate after the burner shuts
off to clear the exhaust vent of combustion gases.
2. The fan may run to help prevent freezing.
1. This is normal operation –no action is required.
2. Protect the boiler from freezing temperatures or
shut off and drain the unit.
White “smoke” can
be seen coming out
of the exterior
exhaust gas vent.
Depending on the outside temperature, water vapor
can be produced as the exhaust is vented.
This is normal operation –no action is required.
No domestic hot
water
Is the indirect water temperature set too low?
Adjust the temperature setting.
Domestic hot water
is too hot
Is the indirect water temperature set too high?
Adjust the temperature setting.
House is not heating
up
Is the CH temperature set too low?
Adjust the temperature setting.
Table 2 –Troubleshooting Chart
This boiler is equipped with a blocked vent shutoff system. If Error Codes Er:20 or Er:29 occur, turn off the gas valve at the manual
shutoff. Check the vent terminations for obstructions. If no obstructions are found, reset the boiler by pressing the power button. If the
error continues to occur, call a qualified service technician or the gas supplier to check the boiler. Failure to follow these instructions
could result in property damage, personal injury, or death.
Er:80 will occur if there is no water in the boiler. Ensure the boiler is full of water and purged of excess air. Then manually reset the
boiler by pressing the power button. If the error continues to occur, call a qualified service technician. Failure to do so could result in
property damage.

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MAINTENANCE NOTES

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LP-543 Rev. 12.15.15