Allied Furnace: Heat exchanger removal, cleaning and reinstallation
Heat exchanger removal, cleaning and reinstallation on a Allied furnace: Clean the heat exchanger when it is fouled. Remove it from the cabinet, wash it, rinse it fully and put it back in the same position. Steps 1 to 20 are not on these pages.
Applies to: 92G1UH furnace
How to fix heat exchanger removal, cleaning and reinstallation: step by step
- Remove the heat exchanger from the cabinet after removing the blower, primary limit, wiring, pressure switch and burner parts as the earlier steps direct.
- Back wash the heat exchanger with soapy water or steam. If steam is used, keep it below 275°F (135°C).
- Rinse and drain the heat exchanger thoroughly, rinsing the whole assembly because soap solutions are corrosive.
- Reinstall the heat exchanger, making sure the rear baffle sits under the support at the back of the cabinet. Check this through the blower opening.
- Re-secure the vestibule side screws, the blower rail screws, the blower deck flange screws and the top cap screws.
- Reinstall the primary limit, wiring, strain relief bushing, pressure switch and its hose to the cold end header collector box.
- Reinstall the 1/2 inch NPT fitting if removed, reconnect drain tubing, condensate trap and junction box.
- Reinstall the combustion air inducer with its flexible connector, reconnect its 2 pin plug, and reconnect the drain tubes between the flue collar and cold end header box.
- Secure the burner assembly to the vestibule with the four existing screws, reconnect gas line, rollout switch, sensor, ignitor and gas valve wires.
- Replace the blower and heating compartment access panels.
- Verify gas and electrical connections before restoring supplies, then light the furnace and run it for 5 minutes to confirm the heat exchanger is clean, dry and operating properly.
If the unit shows an error code, look it up: Allied Furnace codes
Source: Allied 92G1UH installation instructions manual, p. 56. Written in our own words as a summary; always check the original manual.
General guidance for qualified technicians. The manufacturer's installation and service manual and local codes always take priority. Aurora Star Tech is not affiliated with, endorsed by or sponsored by any equipment manufacturer; brand and model names are used only to identify equipment and belong to their owners.