Goodman Blower Speed - http://www.hvacmechanic.com/ Forums

Original message

k_in_in

206.246.149.170

"Goodman Blower Speed" , posted Fri 8 Feb 09:25

I am looking for some help with a goodman heat pump. It seems that the air flow through the air handler is too much. Using the tempurature rise method I calculated the air flow to be 1600 cfm. This is a 2.5 ton unit so the air flow should be down around 1000 cfm. The fan is already set to the slowest setting (red wire). Is there another way to slow the fan down further. My readings were 20 degree rise with a 10KW electric heating element.

Any help would be great.

Replies:

dwcaveney

69.104.141.19

"Re(1):Goodman Blower Speed" , posted Tue 12 Feb 21:08

Sir:
Forget about my earlier posts. I think you need to turn your fan speed up not down. There is some what of a paradox with air speed and volumn as it pertains to comfort. With a lower fan speed you get a higher temp rise in the unit, but not enough pre-warmed air to your return. I had a similar problem with my furnace. I turned it down and the air comes out hotter but the house is not as warm as it was at a higher speed. Try turning it up. It might just work. I am going to raise my fan speed back up tomorrow. Sorry about all that technical stuff I posted, I didn't fully understand it my self.
Good Luck
DC Draftworks

theduke03

24.250.19.62

"Re(1):Goodman Blower Speed" , posted Fri 8 Feb 22:28

How can you use the temp rise method on a heat pump to calculate airflow? You can't. How could the air handler be moving too much air, especially on the slowest speed? That would be possible if the indoor and outdoor units were mismatched. Need more info.

You can't put a price on comfort! Be Safe.

k_in_in

72.171.0.140

"Re(2):Goodman Blower Speed" , posted Fri 8 Feb 23:42

I used the temp rise method by turning off the heat pump and turning on the 10kw electric heating elements. This gives me a know input for the formula. With the heat pump off and only the 10kw elements on my temp rise was 20 degrees. It does not seem posible to me to have to much air flow, but I can not think of anything else that would keep the temp rise so low with the 10kw elements on. I figured I should be about 30 degree rise with this situation.

Thanks

dwcaveney

69.104.141.19

"Re(3):Goodman Blower Speed" , posted Sat 9 Feb 00:57:

Prior post deleted by sender dwcaveney for the following reasons: inaccurate, presumptious, confusing and of no practical value.
Please excuse me.

Daniel

[this message was edited by dwcaveney on Tue 12 Feb 21:16]