VI. Periodic Preventative Maintenance

NOTE: Periodic inspection and preventive maintenance of your total heating system is important for efficient and safe operation. Your heating contractor should include humidifier service at the same time.

All models, except No’s. 448 and 445, are equipped with an in-line water strainer and orifice as shown below. These parts should be inspected and cleaned periodically to assure contin- ued proper unit performance.

Inspection and

Service Instructions

1.Disconnect electrical power to the furnace and shut off water supply.

2.Disconnect the water line at the inlet com- pression nut.

3.Remove the in-line strainer from inside the inlet fitting by using a small nail or wire.

4.Flush the in-line strainer clean or replace with a new strainer, Service Department, Part No. 4004.

5.Replace the in-line strainer and reconnect the inlet water line (Double Wrench To Prevent Leaking).

6.Disconnect the water line at the outlet com- pression nut.

7.Remove the orifice from the copper or plas- tic tube and make sure this small opening is unplugged.

8.Replace the orifice and reconnect the outlet water line (Double Wrench To Prevent Leaking).

9.Turn on water supply and reconnect electrical power to the furnace.

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