Lochinvar WH 55 - 399 Guide

User’s Information Manual
Models: WH 55 - 399
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.
This appliance MUST NOT be installed in any location where
gasoline or flammable vapors are likely to be present.
WHAT TO DO IF YOU SMELL GAS
• Do not try to light any appliance.
• Do not touch any electric switch; do not use any phone in your
building.
• Immediately call your gas supplier from a near by phone.
Follow the gas supplier’s instructions.
• If you cannot reach your gas supplier, call the fire department.
• Installation and service must be performed by a qualified
installer, service agency, or the gas supplier.
WARNING
Save this manual for future reference.
WH-USER Rev B

2
Hazard definitions
The following defined terms are used throughout this manual to bring attention to the presence of hazards of various risk levels
or to important information concerning the life of the product.
DANGER
WARNING
CAUTION
CAUTION
NOTICE
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 indicates special instructions on installation, operation, or maintenance that are important but not
related to personal injury or property damage.
Contents
HAZARD DEFINITIONS..................................................... 2
PLEASE READ BEFORE PROCEEDING......................... 3
1. PREVENT COMBUSTION AIR CONTAMINATION ..... 4
2. MAINTENANCE SCHEDULE ....................................... 5
Maintenance Procedures................................................... 6
Boiler Must Be Serviced and Maintained .................... 6
Check Boiler Area......................................................... 6
Check Pressure Temperature Gauge........................... 6
Check Vent Piping........................................................ 6
Check Air Piping........................................................... 6
Check Relief Valve....................................................... 6
Check Condensate Drain System ............................. 6-7
Test Low Water Cutoff (if installed).............................. 8
Reset Button (low water cutoff).................................... 8
Check Boiler Piping (gas and water)............................ 8
Operate Relief Valve .................................................... 8
Shut Boiler Down.......................................................... 8
3. OPERATING INSTRUCTIONS..................................... 9
4. SMART SYSTEM CONTROL MODULE
SMART SYSTEM Control Module................................... 11
Access Modes ............................................................ 11
Saving Parameters..................................................... 11
Adjusting Parameters ............................................ 11-12
Status Display Screens ......................................... 13-15
Revision Notes.................................................. Back Cover

User’s Information Manual
Please read before proceeding
The Knight Wall Mount Installation and
Operation Manual along with the Knight
Wall Mount Service Manual are for use
only by a qualified heating installer/service
technician. Refer only to this User’s
Information Manual for your reference.
Improper installation, adjustment,
alteration, service or maintenance can
cause property damage, personal injury
(exposure to hazardous materials) or loss
of life. Installation and service must be
performed by a qualified installer, service
agency or the gas supplier (who must
read and follow the supplied instruction
before installing, servicing, or removing
this boiler. This boiler contains materials
that have been identified as carcinogenic,
or possibly carcinogenic, to humans).
Failure to adhere to the guidelines on this
page can result in severe personal injury,
death, or substantial property damage.
Boiler service and maintenance –
• To avoid electric shock, disconnect electrical supply
before performing maintenance.
• To avoid severe burns, allow boiler to cool before
performing maintenance.
Boiler operation –
• Do not block flow of combustion or ventilation air to
the boiler. This boiler is equipped with a control which
will automatically shut down the boiler should air or
vent be blocked. If vent or air blockage is easily
accessible and removable, remove it. The boiler should
attempt to restart. If blockage is not obvious or cannot
be removed, have the boiler and system checked by a
qualified service technician.
• Should overheating occur or gas supply fail to shut off,
do not turn off or disconnect electrical supply to the
circulator. Instead, shut off the gas supply at a location
external to the appliance.
• Do not use this boiler if any part has been under water.
The possible damage to a flooded appliance can be
extensive and present numerous safety hazards. Any
appliance that has been under water must be replaced.
Boiler water –
• Thoroughly flush the system (without boiler
connected) to remove sediment. The high-efficiency
heat exchanger can be damaged by build-up or
corrosion due to sediment.
• Do not use petroleum-based cleaning or sealing
compounds in the boiler system. Gaskets and seals in
the system may be damaged. This can result in
substantial property damage.
• Do not use “homemade cures” or “boiler patent
medicines”. Serious damage to the boiler, personnel,
and/or property may result.
• Continual fresh make-up water will reduce boiler life.
Mineral buildup in the heat exchanger reduces heat
transfer, overheats the stainless steel heat exchanger,
and causes failure. Addition of oxygen carried in by
makeup water can cause internal corrosion. Leaks in
boiler or piping must be repaired at once to prevent
makeup water.
Freeze protection fluids –
• NEVER use automotive antifreeze. Use only inhibited
propylene glycol solutions, which are specifically
formulated for hydronic systems. Ethylene glycol is
toxic and can attack gaskets and seals used in hydronic
systems.
When calling or writing about the boiler
– Please have the boiler model and serial
number from the boiler rating plate.
Consider piping and installation when
determining boiler location.
Any claims for damage or shortage in
shipment must be filed immediately
against the transportation company by the
consignee.
Factory warranty (shipped with unit) does
not apply to units improperly installed or
improperly operated.
3
NOTICE
WARNING
NOTICE

User’s Information Manual
1 Prevent combustion air contamination
4
If the boiler combustion air inlet is located
in a laundry room or pool facility, for
example, these areas will always contain
hazardous contaminants.
To prevent the potential of severe
personal injury or death, check for areas
and products listed in Table 1A before
installing the boiler or air inlet piping.
If contaminants are found, you MUST:
• Remove contaminants permanently.
—OR—
• Relocate air inlet and vent
terminations to other areas.
WARNING
WARNING
Products to avoid:
Spray cans containing chloro/fluorocarbons
Permanent wave solutions
Chlorinated waxes/cleaners
Chlorine-based swimming pool chemicals
Calcium chloride used for thawing
Sodium chloride used for water softening
Refrigerant leaks
Paint or varnish removers
Hydrochloric acid/muriatic acid
Cements and glues
Antistatic fabric softeners used in clothes dryers
Chlorine-type bleaches, detergents, and cleaning solvents
found in household laundry rooms
Adhesives used to fasten building products and other
similar products
Areas likely to have contaminants
Dry cleaning/laundry areas and establishments
Swimming pools
Metal fabrication plants
Beauty shops
Refrigeration repair shops
Photo processing plants
Auto body shops
Plastic manufacturing plants
Furniture refinishing areas and establishments
New building construction
Remodeling areas
Garages with workshops
Table 1A Corrosive Contaminants and Sources
WARNING If the boiler combustion air inlet is located
in any area likely to cause contamination,
or if products which would contaminate
the air cannot be removed, you must
have the combustion air and vent
re-piped and terminated to another
location. Contaminated combustion
air will damage the boiler, resulting in
possible severe personal injury, death, or
substantial property damage.
Pool and laundry products and common household
and hobby products often contain fluorine or chlorine
compounds. When these chemicals pass through the boiler,
they can form strong acids. The acid can eat through the
boiler wall, causing serious damage and presenting a possible
threat of flue gas spillage or boiler water leakage into the
building.
Please read the information listed in Table 1A. If
contaminating chemicals will be present near the location of
the boiler combustion air inlet, have your installer pipe the
boiler combustion air and vent to another location, per the
Knight Wall Mount Installation and Operation Manual.

User’s Information Manual
2 Maintenance schedule
5
Service technician
(see the Knight Wall Mount Service Manual)
General:
• Reported problems
• Inspect interior; clean and vacuum if
necessary
• Clean condensate trap and fill with fresh
water
•Check for leaks (water, gas, flue,
condensate)
• Verify flue and air lines in good condition
and sealed tight
•Check system water pressure/system
piping/expansion tank
• Check control settings
•Ignition and flame sense electrodes
(sand off any deposits; clean and
reposition)
• Wiring and connections
•Perform start-up checkout and
performance verification per Section 10
in the Knight Wall Mount Installation and
Operation Manual.
• Flame inspection (stable, uniform)
• Flame signal (at least 4 mA)
•Clean the heat exchanger if flue
temperature is more than 54°F above
return water temperature.
If combustion or performance
indicate need:
• Clean heat exchanger
•Remove and clean burner using
compressed air only
• Clean the blower wheel
Owner maintenance
(see pages 6 - 8 for detailed instructions)
Daily
• Check boiler area
•Check pressure/temperature
gauge
Monthly
• Check vent piping
• Check air piping
• Check air and vent termination
screens
• Check relief valve
• Check condensate drain system
Periodically • Test low water cutoff (if used)
• Reset button (low water cutoff)
Every
6 months
•Check boiler piping (gas and
water) for leaks
• Operate relief valve
End
of season
months
•Shut boiler down (unless boiler
used for domestic hot water)
WARNING Follow the maintenance procedures given throughout this manual. Failure to perform the service and
maintenance or follow the directions in this manual could result in damage to the boiler or system,
resulting in severe personal injury, death, or substantial property damage.
ANNUAL START-UP

User’s Information Manual
2 Maintenance schedule
6
Maintenance procedures
Boiler must be serviced and maintained
WARNING The boiler must be inspected and started
annually at the beginning of the heating
season by a qualified service technician.
In addition, the maintenance and care
of the boiler designated on page 5 of this
manual and explained on pages 6 through
8 must be performed to assure maximum
boiler efficiency and reliability. Failure to
service and maintain the boiler and system
could result in equipment failure, causing
possible severe personal injury, death, or
substantial property damage.
NOTICE The following information provides
detailed instructions for completing
the maintenance items listed in the
maintenance schedule on page 5. In
addition to this maintenance, the boiler
must be serviced and started up at the
beginning of each heating season by a
qualified service technician.
Check boiler area
WARNING To prevent potential of severe personal
injury, death, or substantial property
damage, eliminate all materials discussed
below from the boiler vicinity and the
vicinity of the boiler combustion air inlet.
If contaminants are found:
Remove products immediately from the
area. If they 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 vent and air piping
and locate vent termination/air intake
away from contaminated areas.
1. Combustible/flammable materials -- Do not store
combustible materials, gasoline or any other flammable
vapors or liquids near the boiler. Remove immediately if
found.
2. Air contaminants -- Products containing chlorine or
fluorine, if allowed to contaminate the boiler intake air,
will cause acidic condensate in the boiler. This will cause
significant damage to the boiler if allowed to continue.
Read the list of potential materials listed in Table 1A on
page 4 of this manual. If any of these products are in the
room from which the boiler takes its combustion air, they
must be removed immediately or the boiler combustion
air (and vent termination) must be relocated to another
area.
Check pressure/temperature gauge
1. Make sure the pressure reading on the boiler pressure/
temperature gauge does not exceed 24 psi. Higher
pressure may indicate a problem with the expansion
tank.
2. Contact a qualified service technician if problem persists.
Check vent piping
1. Visually inspect the flue gas vent piping for any signs of
blockage, leakage, or deterioration of the piping. Notify
your qualified service technician at once if you find any
problems.
WARNING Failure to inspect the vent system as noted
above and have it repaired by a qualified
service technician can result in vent system
failure, causing severe personal injury or
death.
Check air piping
1. Visually inspect the air inlet termination to be sure it is
unobstructed. Inspect the entire length of air piping to
ensure piping is intact and all joints are properly sealed.
2. Call your qualified service technician if you notice any
problems.
Check relief valve
1. Inspect the boiler relief valve and the relief valve
discharge pipe for signs of weeping or leakage.
2. If the relief valve often weeps, the expansion tank may
not be working properly. Immediately contact your
qualified service technician to inspect the boiler and
system.
Check condensate drain system
Inspect/check condensate lines and fittings
1. Inspect the condensate drain line, condensate fittings and
condensate trap.
2. Fill condensate trap with enough water to make the ball
float (FIG. 2-1).
3. Loosen compression fitting (FIG. 2-1).
4. Slide condensate trap onto condensate drain at the
bottom of the unit.
5. Tighten compression fitting.

User’s Information Manual
2 Maintenance schedule (continued)
7
Clean/Inspect Trap Assembly
1. Remove the clean out cap on the bottom of the trap. Let
the condensate and any debris drain out.
2. Refill the trap according to the instructions on page 6.
WARNING
Figure 2-1 Condensate Trap
Condensate disposal
1. This boiler is a high efficiency appliance that produces
condensate.
2. The bottom of the boiler has a 1 1/4 inch pipe for
connection of the condensate trap (FIG. 2-2).
3. Slope condensate tubing down and away from the
boiler into a drain or condensate neutralizing filter.
Condensate from the Knight wall mount boiler will be
slightly acidic (typically with a pH from 3 to 5). Install
a neutralizing filter if required by local codes.
A Neutralizer Kit is available from the factory (Kit
3087).
4. Do not expose condensate line to freezing temperatures.
5. Use only plastic tubing or piping as a condensate drain
line (FIG. 2-2).
Use materials approved by the authority
having jurisdiction. In the absence of
other authority, PVC and CPVC pipe
must comply with ASTM D1785 or D2845.
Cement and primer must comply with
ASME D2564 or F493. For Canada use
CSA or ULC certified PVC or CPVC pipe,
fittings, and cement.
6. A condensate removal pump is required if the boiler is
below the drain. When installing a condensate pump,
select one approved for use with condensing boilers
and furnaces. The pump should have an overflow
switch to prevent property damage from condensate
spillage. Call your qualified service technician to inspect
the boiler and system.
NOTICE
NOTICE To allow for proper drainage on large
horizontal runs, a second line vent may
be required and tubing size may need to
increase to 1 inch.
The condensate line must remain
unobstructed, allowing free flow of
condensate. If condensate is allowed to
freeze in the line or if the line is obstructed
in any other manner, condensate can exit
from the boiler tee, resulting in potential
water damage to property. Call your
qualified service technician to inspect
the boiler and system.
Figure 2-2 Condensate Disposal
The condensate trap (FIG. 2-1) must have
the float ball in place during all times of
boiler operation to avoid flue gas emission
from the condensate drain line. Failure to
ensure the float ball is in place could result in
severe personal injury or death.
CONDENSATE
DRAIN
REMOVABLE CAP TO
CLEAN OUT TRAP
FLOAT BALL
COMPRESSION
FITTING
CONDENSATE
TRAP
REMOVABLE CAP
FOR CLEANING TRAP
CONDENSATE DRAIN CONNECTION -
ROUTE TO FLOOR DRAIN OR
NEUTRALIZING FILTER USING
3/4" CORRUGATED TUBING
SECURE INTO
CONDENSATE DRAIN
STAND PIPE
CONDENSATE DRAIN
STAND PIPE

User’s Information Manual
2 Maintenance schedule
8
WARNING Have leaks fixed at once by a qualified
service technician. Failure to comply could
result in severe personal injury, death, or
substantial property damage.
Operate relief valve
1. Before proceeding, verify that the relief valve outlet has
been piped to a safe place of discharge, avoiding any
possibility of scalding from hot water.
WARNING To avoid water damage or scalding due
to valve operation, a metal discharge
line must be connected to the relief
valve outlet and run to a safe place of
disposal. This discharge line must be
installed by a qualified heating installer or
service technician in accordance with the
instructions in the Knight Wall Mount
Installation and Operation Manual. The
discharge line must be terminated so as
to eliminate possibility of severe burns
or property damage should the valve
discharge.
2. Read the boiler pressure/temperature gauge to make
sure the system is pressurized. Lift the relief valve
top lever slightly, allowing water to relieve through
the valve and discharge piping.
3. If water flows freely, release the lever 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 seat again to
attempt to clean the valve seat. If the valve continues to
weep afterwards, contact your qualified service
technician to inspect the valve and system.
4. If water does not flow from the valve when you lift the
lever completely, the valve or discharge line may be
blocked. Immediately shut down the boiler, following
the operating instructions on pages 9 and 10 of this
manual. Call your qualified service technician to inspect
the boiler and system.
Shut boiler down (unless boiler is used
for Domestic Water)
1. Follow “To Turn Off Gas to Appliance” on pages 9 and 10
of this manual.
2. Do not drain the system unless exposure to freezing
temperatures will occur.
3. Do not drain the system if it is filled with an antifreeze
solution.
4. DO NOT shut down boilers used for domestic water
heating, they must operate year-round.
3. Replace the front access door.
Test low water cutoff (if installed)
1. If the system is equipped with a low water cutoff,
test the low water cutoff periodically during the heating
season, following the low water cutoff manufacturer’s
instructions.
Reset button (low water cutoff)
1. Testing the low water cutoff shuts the unit off. Press the
RESET button on the low water cutoff to turn the unit
back on.
Check boiler piping (gas and water)
1. Remove the boiler front access door and perform a gas
leak inspection per steps 1 through 7 of the Operating
Instructions on pages 9 and 10. If gas odor or leak is
detected, immediately shut down the boiler following the
procedures on pages 9 and 10. Call a qualified service
technician.
2. Visually inspect for leaks around water piping.
Also inspect the circulators, relief valve, and fittings.
Immediately call a qualified service technician to repair
any leaks.

User’s Information Manual
9
3 Operating instructions
o
Figure 3-1 Operating Instructions - Models 55 - 285

User’s Information Manual
10
3 Operating instructions
Figure 3-2 Operating Instructions - Model 399