Thermo Products CMA1-50N, CMA2-75N service manual F.Furnace Checkout Procedure

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All installations and services must be performed by qualified service personnel.

control, with one of the higher speed blower leads attached to a terminal marked “Park”. Be sure to attach any unused blower leads to a terminal marked “Park”. Replace the blower door and turn on the power supply.

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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Contents FOR YOUR SAFETY INSTALLATION AND SERVICE MANUALGAS FIRED HIGH EFFICIENCY FURNACE DOWN FLOW & DIRECT VENT SEALED COMBUSTIONSECTION TABLE OF CONTENTSI. SAFETY INFORMATION Page Page The vent and air intake elbows must be kept away from bushes, shrubs or any vegetation that may restrict the flow of flue products. It must also be kept clear of any leaves, weeds or other combustible materials. Keep the vent hood clear of snow. Avoid locating the terminals in areas where standing water or condensate drippage may be a problem 1.A windows be opened DIMENSIONS II. FURNACE SPECIFICATIONS - CMA SERIESMODEL GAS SUPPLY PRESSUREINSTALLATION PARTS PACKAGE NON-COMBUSTIBLEMATERIAL COMBUSTIBLE MATERIAL.” COMBUSTIBLE MATERIALTable IV. GENERAL INSTALLATION A.FURNACE LOCATIONMODELS CMA Figure 1B Combustible Floor Base Model: 70-BASE Figure 1ACoil Cabinet Cottage Base Model: 01COT-BASE Figure 1C Figure Figure B. BASE INSTALLATION1. Combustible Floor Base Model: 70 BASE Figure C. ALCOVE INSTALLATION2. Cottage Base Model: 01COT BASE Figure D. CLOSET INSTALLATIONE. FUEL PIPING F.GENERAL VENTING REQUIREMENTS Table MAXIMUM VENT LENGTHFigure 6. CMA*-75SHOWN 1. Vent And Combustion Air Pipes H. Direct Venting Through a Sidewall2. Exhaust Vent Termination Elbow Sidewall Venting Page 4. Vent Terminal Location Guidelines Terminations Figure Figure 5.Secure plate to roofFigure K.CONDENSATE DRAIN LINE AND TRAP ASSEMBLY 2.Connection Of Power Supply Wires Figure L.ELECTRICAL WIRING3.Connection Of Room Thermostat Wires 1. Electrical Branch Supply CircuitElectrical Wire Diameter AWG 24 22 20 18 4. BLOWER MOTOR SPEED WIRING Figure Speed Tap \ CMA1-50Static PressureSpeed Tap \ CMA2-75Static Pressure5. FIELD WIRING AND REPLACING WIRING V.STARTING THE UNIT A. SEQUENCE OF OPERATIONS MAIN BURNER OPERATION CALL FOR HEAT SATISFIED OPERATING INSTRUCTIONS B.INITIAL START UPC.ADJUSTMENT OF BTU INPUT RATE D.BURNER ADJUSTMENT GAS PRESSURE CHART FOR CMA* MODEL FURNACESFigure E.SETTING TEMPERATURE RISEF.FURNACE CHECKOUT PROCEDURE VII. DEALER MAINTENANCE VI. INSTALLERS INSTRUCTIONS TO USER4. INDUCER BLOWER ASSEMBLY 2.CONDENSATE LINE/TRAP ASSEMBLYA.ELECTRICAL B.GENERAL INSPECTION5. GASKETS/SEALING MATERIALS 1.CLEANING THE COIL AIR SIDEC.HEAT EXCHANGER D.HOUSE AIR BLOWERFILTER REPLACEMENT FILTER MAINTENANCE PROCEDUREVIII. TROUBLESHOOTING DIAGNOSTIC FEATURESThe LED will also flash once at power-up TROUBLESHOOTING GUIDE AT THE INTEGRATED CONTROL? Yes AFTER GAS VALVE OPENS, DO THE BURNERS IGNITE? DOES SYSTEM RUN UNTIL THERMOSTAT IS SATISFIED? IF LED LIGHT FLASHES APPENDIX – A REPLACEMENT PARTS Page APPENDIX – B WIRING DIAGRAM