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SERVICE AND TECHNICAL SUPPORT MANUAL
Gas Furnace: N9MSB
Specifications subject to change without notice.
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2. Turn off gas and electrical supplies to your furnace.
3. Remove furnace control door.
4. Remove the top unused rubber plug from the port on the
collector box opposite the condensate trap. (See
5. Connect a field supplied 3/8
−
in. (9.5
−
mm) ID tube to the
open port on the collector box
6. Insert a field supplied funnel into the tube.
7. Pour 1 quart of anti
−
freeze solution into the funnel/tube.
Antifreeze should run through the collector box, overfill
condensate trap and flow to an open drain.
8. Replace the rubber plug in the port on the collector box.
9. Remove the middle unused rubber plug from the port on
the collector box opposite the condensate trap. See
10. Repeat Steps 5 through 8.
11. If a condensate pump is used, check with pump
manufacturer to verify pump is safe for use with
antifreeze used. Allow pump to start and pump
anti
−
freeze to open drain.
12. Replace main door.
13. When furnace is re
−
started, flush condensate pump with
clear water to check for proper operation before
re
−
starting furnace.
14. Propylene glycol need not be removed before re
−
starting
furnace.