How much should it cool?


  #1  
Old 05-23-09, 05:11 PM
A
Member
Thread Starter
Join Date: Apr 2009
Location: Washington DC
Posts: 8
Upvotes: 0
Received 0 Upvotes on 0 Posts
How much should it cool?

Our heat pump was recently repaired, and now cools air about 17 degrees. (e.g. when it's 80 outside, the air from the ducts is 63)

Is this normal/acceptable?
 
  #2  
Old 05-24-09, 08:52 AM
airman.1994's Avatar
Member
Join Date: Dec 2005
Location: VA
Posts: 5,491
Upvotes: 0
Received 8 Upvotes on 8 Posts
Yep it's in line!!!!!!!!!!!!!!!!!
 
  #3  
Old 05-24-09, 04:00 PM
E
Banned. Rule And/Or Policy Violation
Join Date: May 2007
Location: Wisconsin
Posts: 7,826
Upvotes: 0
Received 1 Upvote on 1 Post
On a regular a/c, it is the inside cold air return air temp that matters.

On heat pumps, is the outside air (per poster's query)the determining factor? If so, then what degree cooling number (like 63) could poster "anomoly"(or anyone) expect, if it was 100 out (but say the house really was still 75 due to overnight low temp) ?
 
  #4  
Old 05-24-09, 04:38 PM
pflor's Avatar
Member
Join Date: Dec 2007
Location: U.S.A.
Posts: 976
Upvotes: 0
Received 0 Upvotes on 0 Posts
17 degrees is good indeed as airman says. 20 is the target number that should be hoped for, but other factors could easily prevent this ideal from being reached.

Also, how long did you wait before taking those readings?
You should have waited a good 15-to-20 minutes so the system has enough time to bring the temperature in your house down to steady state conditions.
 
  #5  
Old 05-25-09, 04:00 PM
HVAC RETIRED's Avatar
Member
Join Date: May 2008
Location: Wisconsin USA
Posts: 664
Upvotes: 0
Received 0 Upvotes on 0 Posts
Originally Posted by anomaly
Our heat pump was recently repaired, and now cools air about 17 degrees. (e.g. when it's 80 outside, the air from the ducts is 63)
Is this normal/acceptable?
The indoor air temp differential depends on the CFM per-Ton of cooling & the humidity level in the home.

If the indoor airflow is between 375 & 450-CFM, then the big factor is the level of humidity or latent load or heat of condensation on the evaporator coils & fins absorbed by the refrigerant& transfered out through the condenser.

The outdoor temp has little effect on the indoor temp split until it gets well above 105-F.

3-ton 13-SEER, 4-ton evaporator; 75 indoor dry bulb; 1434-CFM; 59-F wet bulb or dry air, split 19-F; 63-IWB 18-F split; 67-IWB, 15-F split; 71-IWB, high humidity, only a 10-F split.
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: