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18400001 a/c control box 4-wire

18400001 a/c control box 4-wire

18400001 a/c control box 4-wire

inside 18400001 control box 4-wire

label 18400001 a/c control box 4-wire

obsolete 18400001 control box 4-wire

18400001 a/c control box 4-wire

Part Number: 18400001
Price: $184.55
Status: Available
Weight: 6 lb, 0 oz
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4-wire control box packages used when adding a/c to most older Coleman Series Pre-1996  Manufactured Housing Gas Furnaces that are not already equipped with a/c. Used with a 4-wire heat/cool thermostat (not included).

Package includes the blower control box wired for 4-wire thermostat (not included) and one 40VA transformer.

This is an updated version of the larger obsolete 7900-6401.  

Installation Instructions:

1.Turn the wall thermostat to its lowest setting. Allow the furnace to shut off completely. Turn off all electrical circuits to the furnace at the main circuit box.

2. Remove the furnace door. 

3. Disconnect the multi-point motor plug from the furnace control panel.

4. Remove the control box from the carton and check for damage. If any damage is visible, do not install; notify carrier.

5. Remove the top cover of the control box and mount bottom half of control box approximately one (1) inch above heating blower mounting screws on blower housing using two (2) self-tapping screws provided (make sure wire harnesses will plug in with no strain on the wiring).

6. Connect  blower motor male plug disconnected in step 4 to the 18400001 control box female pigtail and connect 18400001 control box male pigtail to the furnace control box. 

7. Remove gray wire from the manual reset upper limit switch located on the blower deck to left of blower assembly and attach yellow wire with male / female connector at this point. Re-attach gray wire to male connector on yellow wire.

8. Replace heating transformer with 40 VA transformer provided in package and wire per diagram.

9. Set appropriate blower speeds on relay and install top cover of control box.

10. Complete all low voltage wiring per T-Stat instructions and wiring diagrams provided. Reapply power.

11. Check operation of heating and cooling systems to determine they are in safe operating condition.

4-wire control box package used when adding a/c to most Coleman gas furnaces that are not already a/c equipped. Used with a 4-wire heat/cool thermostat.

Package includes a 40VA transformer, blower relay, isolating relay, thermostat, box & mounting bracket.

Replaces 7900-6041.

Info Sheet