Furnace Checkout Procedure - Thermo Pride CMA3-50D36N Installation And Service Manual

F. FURNACE CHECKOUT PROCEDURE
Before any system of gas piping is finally put into service, it shall be carefully
tested to assure that it is gas tight as indicated in the Fuel Piping Section of this
Furnace Manual.
NOTICE: All controls on the unit should be checked for proper functioning prior to
the qualified service personnel leaving the job site. Specifically the following
should be checked:
With furnace in normal heating operation, check to make certain blower will start
and stop automatically under control of integrated fan control.
1. Check safety limit control as follows:
a. Shut off incoming power.
b. Block return air opening or disconnect blower motor leads.
c. Restore power to furnace.
d. Set thermostat above room temperature calling for heat.
e. When temperatures are reached in furnace at limit control setting with
blower out of operation, burner should shut off.
f. Shut off electrical power.
IMPORTANT: Remove blockage or reconnect blower motor and restore power.
2. Make certain thermostat will automatically start and stop furnace.
3. Block the flue pipe outlet gradually with a flat piece of metal, until the pressure
switch functions shutting off the main burners. IMPORTANT: Remove flue outlet
blockage when done.
4. Block the PVC pipe inlet gradually with a flat piece of metal until pressure
switch functions shutting off the main burners. IMPORTANT: Remove air inlet
blockage when done.
5. Remove the blower compartment access door with the furnace operating. The
door interrupt switch is in the 120 volt circuit and will shut down the entire
system. Replace the blower door and the furnace start-up cycle will begin.
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