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Matthew, HVAC Technician
Category: HVAC
Satisfied Customers: 2014
Experience:  14 years experience in the HVAC field of service, installation, Manual J & D calculations
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i have a rheem imperial 80 plus furnace 25 yrs old.burner was

Resolved Question:

i have a rheem imperial 80 plus furnace 25 yrs old.burner was going off and on,put vaccum on pressure hose works fine,replaced pressure switch and hose cleaned out what hose attachs to,inducer seems to be working fine, still doing same thing,is it possible its the inducer motor
Submitted: 7 years ago.
Category: HVAC
Expert:  Matthew replied 7 years ago.

My name is XXXXX XXXXX I will do my best to help you today.


When it does light the burners how long do they stay on and when they go off how long do they stay off before it lights them again?


Also this furnace was re engineered a bunch of times as it was one of the first automatic ignition systems out there back in 1985. Does it have a fan limit relay on this particular unit it looks like this....



Edited by Matthew on 5/1/2010 at 2:33 AM EST
Customer: replied 7 years ago.
it does have a fan and limit, the burners kick on and off in a second or two, but like i said everything works fine if suction put on pressure hose and crimped
Expert:  Matthew replied 7 years ago.

oh, I misunderstood sorry. If you can manually pull in the pressure switch and it works then we know it is in the exhaust system.


Did you clean the barb on the inducer housing where the tube hooks up?


Take the vent pipe off the top of the furnace and see if the furnace stays on. If it does then the vent is restricted. If it doesn't work still then we know it is either the inducer draft motor not running at the proper RPM to pull in suction or the pressure switch itself but you said you changed the switch already.

Edited by Matthew on 5/1/2010 at 2:59 PM EST
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