HTP MC120 - Manual (Page 69)

69
LP-171 Rev. 4.10.14
2. Using a spray bottle filled with calcium and lime deposit remover, spray liberally on the coils, making sure the solution penetrates and
funnels down through the condensate hose. If the condensate hose is blocked, let the chemical penetrate for at least 15 minutes or until
it drains.
3. Use the nylon, stainless or brass brush (do not use steel) and scrub coils to remove any buildup. Then vacuum the debris from the
coils. WARNING: Follow above precautions.
4. Spray the coils with clear water, making sure to confine the spray to the area being cleaned (try to avoid getting the back ceramic
wall of the unit wet). Flush the combustion chamber with fresh water. At this point, the heater should be ready to power back up.
Before powering up the heater follow the steps below:
a. Re-install the burner assembly.
b. Replace the (4) 10MM nuts to the burner plate.
c. Re-connect all wiring connections.
e. Replace the (4) screws on the aluminum ½” NPT connector on the gas valve. Turn the gas back on. (IMPORTANT: CHECK
FOR GAS LEAKS.)
f. Re-set thermostats (IMPORTANT: MAKE SURE EXHAUST VENT IS NO LONGER BLOCKED!)
g. Turn the heater back on and observe condensate flow.
h. Re-connect the condensate hose to the outside connection.
Do not use solvents to clean any of the burner components. The components could be damaged, resulting in unreliable or unsafe
operation. Failure to do so could result in death or serious injury.
D. MAINTENANCE SCHEDULE FOR THE OWNER
The following information provides detailed instruction for completing maintenance items. In addition to this maintenance, the heater
should be serviced at the beginning of the heating season by a qualified service technician.
Periodically

Check area around the unit.
o Review Table 1 - Contaminant Table, p. 13. If contaminates are found:
 Remove contaminates immediately from area.
 If contaminates have been in the area for an extended period, call a qualified service technician to inspect
the unit for possible acid corrosion damage.
 If contaminates cannot be removed, immediately call a qualified service technician to re-pipe the combustion
air inlet piping and locate the intake away from contaminated areas.
o Do not store combustible materials, gasoline, or other flammable vapors or liquids near the unit. If found, remove
these materials immediately.

Check and remove any blockage from the combustion air inlet and ventilation openings.
o If removing debris does not allow the unit to operate correctly, contact a qualified service technician to inspect the unit
and the vent/combustion air system.

Check the temperature and pressure gauge.
o Ensure the pressure reading on the gauge does not exceed 25 psig. Higher pressure readings may indicate a
problem with the expansion tank.
o Ensure the temperature on the LED display panel does not exceed 180
o
F. Higher temperature readings may indicate
a problem with the thermostat operating controls.
o Contact a qualified service technician if problem persists.
Monthly

Check vent piping.
o Visually inspect the flue gas vent piping for any signs of blockage, leakage, or deterioration. Ensure that vent piping is
properly supported as described in this manual. 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
substantial property damage, severe personal injury, or death.

Check combustion air inlet piping.
o Visually inspect the air inlet piping for any signs of blockage. Inspect the entire length of the intake to ensure piping is
intact and all joints are properly sealed and supported. Notify a qualified service technician if any problems are found.

Check the pressure relief valve.