Air Flow ProblemsI have a Lennox 3 ton downstairs unit; it is going on 8 years old. I

[turtledove773]

I have a Lennox 3 ton downstairs unit; it is going on 8 years old. I had horrible issues with it last year that seemed to finally be resolved but now this year it starts again! The temperature in our area has been extremely hot for the last couple of weeks high 90’s some days reaching the 100’s. When the weather started getting hotter the airflow of the unit just stopped, the unit is still running but no air, it seems to work for longer periods during the cooler temperatures in late evening/early morning.
At first the company we have been using came out and serviced the unit and topped it off with Freon and then left, not even 10 minutes later the air stopped again. They came out again and replaced the fan motor; it worked for a full day and then went out again. The owner of the company came out and replaced a compressor that he said was the wrong type for the motor. The unit was working fine when he left and then an hour later the air went off again. We have the thermostat on 75 and each time the air stops blowing before it reaches that temperature. The company is coming out to replace the new motor today.
My question is, is there any other reason besides the fan motor that would cause the air to stop blowing?

[m kilgore]

Would need model numbers to see what equipment we are dealing with. To answer your question, yes there are other things that may effect the motor operation. Sounds like they are not catching the unit doing whatever it is doing and are trying to change parts without knowing.

Sometimes it takes a few trips to find a intermintent proplem. Hopefully they can catch it not running and fix the right problem.

[turtledove773]

Thanks for answering! Unfortunatley I am at work and do not have access the the model information. When they came out and replaced the motor the first time they did catch it not running. I guess I'm just trying to determine if something else would prevent the motor from running or are do these guys just not know what they are doing?

[DanW13]

Seems only logical to call them out again and have them change the motor or compressor again but don't let them leave right away, have them stick around for a hr. or so and hopfully the problem will happen agina and they will be there this time

[beenthere]

They probably changed the capacitor, not the compressor.

Sounds like you got the wrong service company.

[m kilgore]

As said probable wrong service company. Changing same parts over and over will not solve the problem. If they were there when it was happening then they should have diagnosed the problem. Sounds like they are just guessing.

Yes there are other things that can cause you to not move any are, in answer to your question.

Good luck

[turtledove773]

**Update**
OK the guy just came back out; I left the unit on when I left this morning so I knew by the time he got out there today it would have quit again so it was not working when he go there.
(Below is the Gist of the conversation I had with him)
According to him the previous fan motor when it went bad sent high amp. to the circuit board which blew out the time delay relay. He redirected it to the contact so it would work but before we have to turn the heat back on we need to replace the circuit board.

I’m going back home at lunch to turn it back on (it had frozen up and had not thawed out when he was ready to leave) and will see if it runs the rest of the day, but does that sound feasible?

[t527ed]

circuit board going bad could cause the problems you are having.

[beenthere]

Thr board may have been the problem all along.

[turtledove773]

That's what I'm thinking and I paid $$$ to have a new motor put in!!!!!!!

[t527ed]

it could have been the motor that damaged the board or it could have been the board all along.

we did not see it or put meters on it so all we can do is speculate.............


not really fair to the guy that was there, doubt he would condem a motor without checking for power first...........

[beenthere]

not really fair to the guy that was there, doubt he would condem a motor without checking for power first...........

Your right, that has never happened.

[Jay 41]

Your right, that has never happened.

It has, but it shouldn't.

[tinknocker service tech]

not the first time a tech tunneled vissioned on just one thing myself included

you very well could have had a two fold problem a bad motor and a weak board. The tech saw the motor and replaced it and leaves not realizing there could be other problem like an intermitant board problem.

this isnt all that uncommon when casing calls and rushing

give the guy a break

[turtledove773]

I just wanted to Thank everyone for answering my questions! It was really helpful! Unit is still running so I'm keeping fingers crossed that the problem has been solved!