Gas and Oil Home Heating Furnaces - No cold air-blower/fan working but not outside unit
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dmorris
08-05-02, 08:14 PM
Tonight my husband replaced the filter in our Lennox furnace. When he finished he replaced the large face plate of the furnace, but the air conditioner did not come back on. The furnace kicks on, but only warm air comes out. The outside a/c unit does not even make a noise like it will come on. It is dark outside, but it does not appear frozen. All seems in working order.
So the problem is basically that the blower comes on inside, but it does not seem like the compessor comes on in the unit outside. Any help would be greatly appreciated!!
Thank you so much!!!
Staci :confused:
So the problem is basically that the blower comes on inside, but it does not seem like the compessor comes on in the unit outside. Any help would be greatly appreciated!!
Thank you so much!!!
Staci :confused:
hvac4u
08-05-02, 09:29 PM
the unit is in the attic, he may have disturbed the float switch in the pan. if the unit drains into a pump, be sure it is working. this should be an easy fix, if the unit was running up until the time he changed the filter
dmorris
08-06-02, 04:49 AM
The air conditioner does drain into a pump which does seem to be working. Is there another possible problem? Thank you for your reply!
bigjohn
08-06-02, 05:05 AM
Some of the pump models are designed so that if the float goes to a real high postion, it cuts off the cooling. Did any wires get disturbed? It could be coincidental. Have you checked the circuit breaker, fuses, looked inside the outdoor unit for a reset button? Look inside the control box in the outdoor unit for the contactor. [a big relay looking thing] Is it pulled in? What happens if you push it in? Are the contact points jammed full of ants/critters? Check these things out and let us know.
dmorris
08-06-02, 04:10 PM
Thank you for your help! Apparently too much pressure built up in the outside unit & it caused a compression switch to flip (I think I said that right). Once that was switched, the air came on and works fine. My husband's cousin (who used to do heating & air)was in the neighborhood, so he checked the pressure in the unit & it is in the normal range. Thanks again for your help!!!!
hvac4u
08-06-02, 08:50 PM
tripped for a reason. if it is the high pressure cutout, be sure to o/d coil is clean and the fan not overheating and quitting on you.