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blairville

Older Lennox airhandler, replaced blower motor but it keeps shutting off

12 posts in this topic

Hello and thanks in advance.

We recently moved into a house where the previous owner trashed every appliance except the dishwasher. We have limited funds so trying to do this on our own. This is a heat pump with inside air handler. It is a lennox Model No. CB29M, and it is old, from 1995. The blower motor was replaced in 2009 with a new run capacitor and again a new capacitor replaced in 2010. The previous owner before bad one kept immaculate records. We saw the blower motor was fried, it was visible. We bought a 1/2 HP, off of Home depot.com, the only difference from burnt one was the amps were 3.5 on the old one and 6.5-9.0 on the new one. Anyway, long story short, we hooked it up, it shuts off within 15 seconds. No clicks, nothing, it just stops. Outside unit is working and coils are clean and cold. The blower motor is also getting very hot, which could be the thermal self protection kicking in and turning itself off. We bought a new capacitor with with the motor and checked it after attempts, and voltmeter says it is fine. Could I please get some guidance as to what to check next? Maybe the blower relay is bad?, but if it was, it would not come on at all, or am  wrong about that? Any advice would be helpful.

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Need appliance parts? Call 877-803-7957 now!

What voltage does the air handler operate on? 120? 240?
What voltage is the old motor?
What voltage is the new motor?
Microfarad )mfd) on the capacitors?
What volt rating for motor capacitors? 370....440?

Correct blower wheel rotation?

What is fan voltage OUT of the relay board?

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Why twice the amperage ? This is the reason for motor

"Frying"

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Why twice the amperage ?

sounds like

the "old" Motor was 220v

and "new" Motor is 120v  :whistling:

 

old Motor part number ?

new Motor part number ?

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According to Lennox motor is 208/230 volt 3 amp

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What voltage does the air handler operate on? 120? 240?

What voltage is the old motor?

What voltage is the new motor?

Microfarad )mfd) on the capacitors?

What volt rating for motor capacitors? 370....440?

Correct blower wheel rotation?

What is fan voltage OUT of the relay board?

It is 240

Voltage for both is the 208-230

10 MFD 370

yes, correct blower wheel rotation because when it was on, it was blowing real hard in the house.

The last question, are you asking about the voltage out of the blower relay?

 

 

sounds like

the "old" Motor was 220v

and "new" Motor is 120v  :whistling:

 

old Motor part number ?

new Motor part number ?

Both motors are 208-230.

Old part Emerson K55HXTGB-8797

New part AO Smith DL1056

 

Like I said before, they were exactly the same except for amperage.

 

 

Should I return the home depot part and get the correct amped one? There is a Grainger store nearby, they have one there.

 

Thanks again for your advice. I don't know when the last motor was "fried". The last owner bought the property in 2010 and moved out april 2012, so this house has been empty since then.

Edited by blairville

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When I ordered the part, the home depot AO Smith part, it said it was the 208-230v, which is obviously incorrect, according to your link above and other ones on the net. That is the first thing I checked. Well there you go. Hopefully after taking this one back and getting the correct one, I will make sure it is the correct voltage, I will get the new part from Grainger, my A/C will work correctly and not shut down. Thanks all, I will update when exchanged.

Edited by blairville

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When I ordered the part, the home depot AO Smith part, it said it was the 208-230v,

should be a model / rating / required capacitor / plate on the Motor

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Well, went to Grainger, got the part. Everything is working fine. Probably needs freon, though. Does not seem to be blowing that cold. What is freon going for these days? It is the R22 type. Wished it was the newer one. It is a Trane, installed in 2007.

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No refrigerant is inexpensive any more.

The price varies across the country.

Could be anywhere from 40 to 100 dollars a pound in your area.

R410a is only slightly less.

EPA.

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