HTP MC120 Installation Start-Up Maintenance Download

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LP-171 Rev. 3.3.15

heater. Installer must also inform the owner that the lack of proper care and maintenance of the heater may result in a hazardous
condition. The installer should discuss the contents of the User's Information Manual with the owner.

BEFORE EACH HEATING SEASON a trained and qualified service technician should perform the inspections and maintenance
procedures as identified in this manual. In addition, the maintenance and care of the heater outlined in this manual must be performed
to assure maximum efficiency and reliability. Failure to do so could result in substantial property damage, serious personal injury, or
death.

The combustion chamber insulation in this product contains ceramic fiber material. Ceramic fibers can be converted to cristobalite in
very high temperature applications. The International Agency for Research on Cancer (IARC) has concluded, “Crystalline silica inhaled
in the form of qu

artz or cristobalite from occupational sources is carcinogenic to humans (Group 1).”



Avoid breathing dust and contact with skin and eyes.



Use NIOSH certified dust respirator (N95). This type of respirator is based on the OSHA requirements for cristobalite at the
time this document was written. Other types of respirators may be needed depending on job site conditions. Current NIOSH
recommendations can be found on the NIOSH website at http://www.cdc.gov/niosh/homepage.html. NIOSH approved
respirators, manufacturers, and phone numbers are also listed on this website.



Wear long-sleeved, loose fitting clothing, gloves, and eye protection.



Apply enough water to the combustion chamber to prevent dust.



Wash potentially contaminated clothes separately from other clothing. Rinse clothes washer thoroughly.

NIOSH stated First Aid.



Eye: Irrigate immediately.



Breathing: Fresh Air.

B. MAINTENANCE SCHEDULE FOR THE SERVICE TECHNICIAN

The following maintenance should be performed annually by a qualified service technician:

General



Attend to any reported problems.



Inspect the interior of the heater jacket area; clean and vacuum if necessary.



Clean the condensate trap and fill with fresh water.



Check for water, gas, flue and condensate leaks.



Verify flue vent piping and air inlet piping are in good condition, properly supported, and tightly sealed.



Check heater 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.



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, review service with the owner.

C. COMBUSTION CHAMBER COIL CLEANING INSTRUCTIONS

*Before beginning this procedure, you must have on hand the following items:



A nylon, stainless or brass brush (not steel)



A liquid calcium and lime deposit remover



Gloves, eye protection

1. Shut down the heater by using the following steps:

a. Close the gas valve, shut down the unit and wait for the unit to be cool to the touch.
b. Disconnect the condensate hose from the

outside

connection,

(not from the heater side)

, so flow can be observed.

c. Disconnect connections from the gas valve, spark electrode and flame rectification probe and combustion blower.
d. Remove the (4) s

crews on the aluminum ½” NPT connector on the gas valve.

e. Disconnect the wiring connected to the combustion blower motor.
f. Remove the (4) 10MM nuts from the burner plate assembly to access the coils.
g. Pull the entire burner plate assembly with blower still attached towards you, while removing or pushing aside any wiring to
allow the removal of the assembly.