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Discussion Starter · #1 ·
I have sealed up all small leaks and have all clean filters/coils.
System is still not blowing strong at all, just barely comes out.

Tech told me about the only thing left is to check the blower in the attic.
Anybody know of a way to check this?
It is a 12 year old furnace and does not have variable speeds.

Thanks
 

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Discussion Starter · #3 ·
Does the blower work at all?
If yes check to see if any of the ducts in the attic have come apart
blower does come on, but only pushes nominal amount of air through vents.
No more leaks or duct issues.

I am looking for a way to test the blower motor to ensure it is running at full capacity if possible.
 

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You need to check if the furnace is set to high speed. Black wire of blower motor on cooling spot at board control.

If it's set to high speed you need to check CFM
 

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did it happen all of a sudden with the lack of air...return grill should hold a sheet of paper with ease...check the rounds on the air handler section might be rounded off with dirt/dust coil is clean after the filter...definite hi speed in cooling for fan...when did it last blast?
 

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Discussion Starter · #6 ·
You need to check if the furnace is set to high speed. Black wire of blower motor on cooling spot at board control.

If it's set to high speed you need to check CFM
Ok thanks for the advice. I checked the wires and they are correct. Also when I kick on heat vs. cool, I can tell when on cool the blower runs stronger.

I see you said to check the CFM, what is that?

thanks
 

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Discussion Starter · #7 ·
did it happen all of a sudden with the lack of air...return grill should hold a sheet of paper with ease...check the rounds on the air handler section might be rounded off with dirt/dust coil is clean after the filter...definite hi speed in cooling for fan...when did it last blast?
It has been a slow volume of air since we have lived her for 3 years. House is 12 years old. Return will hold paper with ease, but just doesn't seem to suck in and push out as much as most other houses. Coils and filter have been cleaned and yes it is definitely on the high speed for cooling.

any other suggestions?
Also I am not sure as to what you mean by, checking the rounds on the air handler. I have opened it up and cleaned inside the blower and furnace.

thanks
 

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Ok thanks for the advice. I checked the wires and they are correct. Also when I kick on heat vs. cool, I can tell when on cool the blower runs stronger.

I see you said to check the CFM, what is that?

thanks

In heat mode, the blower speed is slower.
 

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It has been a slow volume of air since we have lived her for 3 years. House is 12 years old. Return will hold paper with ease, but just doesn't seem to suck in and push out as much as most other houses. Coils and filter have been cleaned and yes it is definitely on the high speed for cooling.

any other suggestions?
Also I am not sure as to what you mean by, checking the rounds on the air handler. I have opened it up and cleaned inside the blower and furnace.

thanks
Sounds like load calculation problem, with ducts not dimensioned rightly.
 

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Remove air filter, and return grille. See if air comes out stronger. if so, you are probably short on return.
 

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Discussion Starter · #13 ·
Remove air filter, and return grille. See if air comes out stronger. if so, you are probably short on return.
I had my wife remove and put in the filter numerous times while I stood under a vent. It was very hard to tell, but I think it changed a very small amount. I am guessing if that was the problem then it would have been more of a drastic change.

If it shouldn't change at all, how would I go about resolving the short on return?


Thanks BeenThere you have been a great help so far.
 

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The return test is often easier to do by removing the blower panel, and bypassing the switch, and seeing if it blows out more air. But due to the heat in an attic from the weather we've been having. Its not a good way to test since it can heat the house up quickly.

If it were a return problem. The solution would be to add another return, or increase the size of the current return duct.
 

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If the blower is operating and the filters are clean check to see if the blower is loose on the shaft.
Make sure you look at all the ducts in the attic to see if any have fallen apart or if any of them are loose.

If the motor is up to speed you should have good air flow.
Is there ice on the evaporator coil?
 
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