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Heating & Air Conditioning

Is my Heat Pump working efficiently?

11 years ago

Greating All.
I just a new Payne heat pump (both indoor unit and outdoorunit). The indoor unit is PF4MNB049 and outdoor PH13NB048. According to the model number, is the system is 4 ton? I know this is not a very good brand, but it was chosen by my home protection company First American. I suspect the system is not working effeciently. I measured the max temperature differencial when aux heating did not kick in. Here are the results:

intake-temp output-temp diff outdoor-temp
64--------------76-----------12----------46
64--------------77-----------13----------48
65--------------83-----------18----------50
65--------------82-----------17----------50

The output temperature is measured at the register which is closed to the air handler, and is warmer than all others. The first two tests were done under normal run which only last one to tow minutes. The last two tests were done after I raised the settiing remperature one more degree so that the system ran longer hence less heat was lost in duct.

Thanks for your advice.

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Comments (3)

tigerdunes
11 years ago
What is thermostat setting?

Where are you measuring the return and supply temperatures?

As far as I am concerned, the supply temps taking into consideration the outside temperature are too low.

While there may be other contributing actors such as ductwork leaks, this issue suggests a poorly charged system.

And one should never ever take a recommendation from these third party warranty companies. Payne s quite low end and usually this attracts low end installs.

IMO
gyyang
Original Author
11 years ago
The thermostat is set to 68 degrees. The return temperature was measured at the return grille and supply temperature was measured at the supply register nearest to the air handler. I used Kintrex infrared themometer to measure them.
I have three return grilles, one on the main floor, one on sedond floor, and a small one in the basement. I understand the return air in the basement is cooler (60 degress), but it probably counts for only 1/5 of air return.

This post was edited by gyyang on Sun, Mar 31, 13 at 23:13
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countryboymo
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It looks like poor numbers but depending on run time and duct leakage and temperature at duct location and many other factors who knows. Some systems take awhile to really start putting out decent temps. If I bumped my stat two degrees and checked it in a couple minutes of run time the numbers would not be great but at 10 minutes would paint a whole different picture.

Mine at 53 degrees outside and the inside temp at 72 is at 92 in 4 minutes and 97.2 at 10 minutes which was not climbing any longer. This is after sealing all of my duct system and checking at the furthest duct in the system. The ductwork is in the basement that is not heated at the moment.

When my ductwork was leaky and I was pulling attic air that might be 20 degrees or 130 degrees and basement air that is usually 60's it really throws numbers out of whack. If you are only conditioning the air that is in the house it makes a huge difference.

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