Aprilaire 700A, 700M, 500M, 600A, 600M, 350 Annual Summer Shutdown, Periodic Preventative Maintenance

ANNUAL SUMMER SHUTDOWN

For Models 400A, 500A, 500M, 600A and 600M close the bypass damper, which is a part of the humidifier, with the small damper handle.

Humidifier Control:

Automatic Digital Humidifier Control in Automatic Mode (see Figure A): No adjustment is necessary.

Automatic Digital Humidifier Control in Manual Mode (see Figure B): Set the knob to the “OFF” position.

Manual Humidifier Control (see Figure C): Set the knob to the “OFF” position.

PERIODIC PREVENTATIVE MAINTENANCE

NOTE: Periodic inspection and preventative maintenance of your total heating system is important for efficient and safe operation. Your heating contractor can service your humidifier at the same time he services the HVAC system.

All models have a distribution tray above the Water Panel, which should be inspected annually and cleaned of excess mineral deposits. Older models have a granular coating in the distribution tray. Do not scrape the granuals out of the tray. Newer models have a fabric liner in the distribution tray.

WATER LINE INSPECTION AND SERVICE INSTRUCTIONS

WATER

FEED TUBE

OUTLET

COMPRESSION

NUT

ORIFICE

SOLENOID

VALVE

INLET

IN-LINE

STRAINER

INLET

COMPRESSION

NUT

90-1053

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

2.Disconnect the water line at the inlet compression nut.

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

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

5.Reconnect the inlet water line. Double Wrench to Prevent Leaking.

6.Disconnect the water feed tube at the outlet compression nut.

7.Inspect the water feed tube by gently flexing it and looking for cracks or signs of wear. Replace tube if it is cracked, brittle, or has been damaged.

8.Inspect the orifice in the water feed tube and make sure the small opening is unplugged.

9.Reconnect the water feed tube. Double Wrench to Prevent Leaking.

10.Remove the drain line from the bottom of the humidifier. If applicable, flex it to loosen any mineral deposits or blockages. Flush the drain line with water under pressure to clear it of any debris, and slip it back onto the drain fitting. If drain line does not flow properly, replace it. Inspect the drain line to make sure it has a constant downward slope and is not flattened or blocked.

11.Turn on water supply and reconnect electrical power to the HVAC.

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