Heat Pump not performing like it should

[Stephen P. Shockley]

Hi,

The issue I'm about to describe isn't from and an inspection. It is from my own house. Outdoor temp here got down to 31 last night. My Heat Pump on the first floor has been running for a long time and only raised the inside temp by 1 degree. It is a Trane XE1000 model. I checked the temps at the registers and got an average of 95 degrees and found 81 degrees at the return. The inside temp has only gone from 67 to 68 in 3 hours. In comparison, the second floor has an identical system and I get 114 degrees at the registors up there. I've never has a problem with this unit until now. We did notice an odd smell when we first turned it on to use it about a week or two ago, but it wasn't the infamous "Dirty-Sock Syndrom" smell. It was more like a burnt bacon smell, however that went a way. I'm going under the house this morning to look around, because a few days ago, I had found a stray cat coming out of my crawl space that must of snuck in when I had the door open last weekend and forgot to close. I looked around for kittens and didn't find any, then closed everything up. The crawlspace entrance is inside the garage.

Regards,

Steve

[Bruce A. King]

Are both of these units 10 SEER that use R22?

I see some things in your post that need confirming.

Why did you have 81 at the return if the downstairs was in the high 60's?
Also, what time of the day/night did you decide to start raising the temperature from 67?

If the upstairs unit was putting out 114 deg air, the electric strips were running also.

The downstairs system, at 31 deg outside will need the aux strips operating some even if R410 system and will need to run them even more if a R22 system.

You need to check the aux heat strips to make sure each section is running.
Also make sure the outside unit is running and not just heating with the aux strips. After confirming all of this, you may need the refrigerant pressures checked.

What is the age of your house, type of windows, sq footage of each level and size/type refrigerant of each system? How do the filters look?

[Stephen P. Shockley]

Are both of these units 10 SEER that use R22? Yes

I see some things in your post that need confirming.

Why did you have 81 at the return if the downstairs was in the high 60's? That's what it read, but I didn't have the louvered door open, just shot the laser in that direction... It has finally gotten up to 72 in here (now 10 AM), so I cranked it up to 76 and checked again. T-stat says 72 (set at 76 to start it up) and return is reading 76.
Also, what time of the day/night did you decide to start raising the temperature from 67? About 6 AM

If the upstairs unit was putting out 114 deg air, the electric strips were running also. That was the reading I got about 5 minutes after turning it on.

The downstairs system, at 31 deg outside will need the aux strips operating some even if R410 system and will need to run them even more if a R22 system.

You need to check the aux heat strips to make sure each section is running. Haven't gotten under the house yet to check any further, but will do this morning, once I get done with the fatherly duties around here...lol
Also make sure the outside unit is running and not just heating with the aux strips. After confirming all of this, you may need the refrigerant pressures checked. Outside unit was running when the T-stat temp was kicked up to turn it on.

What is the age of your house, type of windows, sq footage of each level and size/type refrigerant of each system? How do the filters look?

House is 12 years old, about 2,300 sq ft (half at each level) with double-hung double pane windows and uses R-22 refrigerant. Filters all replaced last weekend.

I checked the temp of the larger line at the pump and it was about 132 degrees, which I believe is what it should be if the outdoor temp was 32.



Thanks for looking at my post and I appreciate the help.


Regards,

Steve

[Wayne B. Wilson]

Low on Freon, Valve stuck, or defrost stuck on.
Touch the suction line on both units and compare at the unit outside.
If it worked last year should be the same . smell could the electric coil coming on from sitting all year

[Kenneth R. Brittain]

Did you check the ducts? A neighbor of mine had a cat under the house and it had tore the flex duct so a lot of conditioned air was dumping under the house.

[Stephen P. Shockley]

Hi Wayne,

If it were a stuck valve wouldn't the air from the registers be all cold air and not feel like luke warm air? Just curious.


Thanks,

Steve

[Wayne B. Wilson]

Yes but the strip heaters may take up the slack

[Wayne B. Wilson]

Did you check the suction line at both units and compare?

[Stephen P. Shockley]

Are you talking about checking the temperature at both ends or checking with a gauge? I don't have any equipment to actually hook up to it.

[Wayne B. Wilson]

Steven use your finger should be the same as the other one or close.
If not you need a ac contractor

[Wayne B. Wilson]

BY the outside unit and inside , Have got any thing to take the temperature of the line?

[Stephen P. Shockley]

Will be going under to check the inside line shortly. However, using an IR laser thermometer in a spot where a little bit of the insulation was deteriated away I got 132 degrees as the highest reading while the unit was running.

Would low refrigerant necessarily indicate a leak if the unit is 12 years old?

[Wayne B. Wilson]

What was the the temp on the unit that is working fine? That seems to be ok
When your under there check for leaks around the duct work including the return air

[Bruce A. King]

When you take readings of supply air you have to remember that most systems turn on the aux heat strips anytime the t-stat is 2-3 degrees higher than the room.

The aux heat will also come on when the t-stat sees a constant drop in performance or a lack of heat gain in the house. The "anticipator" is now programmed into these t-stats.


The systems that have lockouts for auto aux heat have special t-stats that have outside temperature sensors also.

I would disable the heat strips during the times you are checking basic heat pump performance temperatures.

The best way to check heat strips is with a clamp on amp meter.
You can easily get an overall current reading at the breaker wires and then proceed to the unit to check individual strip sections. The kw's of the aux kits range from 5, 7.5 to 10 on most units and you could have different ones on both systems.

[Stephen P. Shockley]

Trying to catch up...had to go into work yesterday and today in the middle of all this. Just getting back to it. Using the IR laser thermometer in a spot on the other unit, I would get as high as 106 deg F in spots. So I guess both were heating up to over 100 deg F when it was 32 deg F outside...