Trane TWR030C heat pump, poor performance..

I have a five year old Trane TWR030C heat pump. As this heating season started I noticed it running excessively. With a measured airflow over the indoor coil of 1100CFM and an outdoor temp of 45Deg I am only getting a temperature rise of 9 degrees over the coil with an indoor air entering temperature of 70 deg.

The compressor current is 8.98 amps with 235Vac in heating mode.

Today it was warm enough to check the temperature and pressure in cooling mode, it warmed up to 65 deg and just made it onto the cooling chart.

ODT 65 deg Suction temp 49 deg High side 135 Low side 76 Indoor air entering temp 70 deg

Low head pressure, High suction pressure. Both readings taken at external service ports.

Any heat pump experts care to comment? Thanks, Dave

Did you try switching the reversing valve while watching your pressures

Dave, Your heat pump is not heating as well as it should. Could you please explain to us exactly how you came up with the measured airflow of 1100 CFM? Bubba

Pappy, I did not try that, sorry...

Bubba, I calculated my airflow by the temperature rise of the gas furnace that is used for backup heat and by looking at the fan speed chart for the furnace, with a measured static pressure of 0.4 to 0.5

Both methods give me airflow of 1100-1200, give or take, which I think is a bit high but not the main issue at hand.

Thanks, Dave

Are there TXV valves in this system?, have you checked pressures in heating mode? Did you try the simple things like making sure the high returns are closed in the heating mode, open in the cooling mode, all registers open, indoor and outdoor coils clean and nothing blocking the airflow, seems when I get gauge readings that are weird its the simple things alot of times

Well, your method/formula seems to be falling apart abit. Your gas furnace blower speed and your heat pump blower speed will usually be different. Are you saying you actually measured the static of your system or did you just grab the number off the fan speed chart? Which static is it? 0.4 or 0.5? Thats a lot of fluctuation if that is your range. What size unit do you have? A 3 ton? Oh, by the way.........unless you have something strange like a 1.5 ton unit........your air flow isnt the problem. Bubba

Try these folks:

Pappy, Thanks for the advice to look at the simple stuff; I would like an easy answer to this. The indoor coil has a fccv, not a txv, but the heat pump does have a txv, don't all heat pumps have one? I did not check any pressures in heating mode.

The indoor coil is clean as new; the outdoor coil looks good but could stand to be washed. I did not think much of it because of the extremely low high side pressure in cooling. Also, the only returns in the house are high air returns.

Bubba, The details of how I determined airflow were; I used a "magnehelic" to measure static pressure from below the coil to a reference point at the filter. The needle actually bounced between 0.4 to 0.5 depending on how the sensing ends were placed in the air stream. I am aware of the difference in using the different motor speeds taps in heating and cooling and moved the taps to see the effect on my readings. The Trane "service facts" sheet has a nice table listing the airflow at the different motor speeds at a given static pressure.

To double check I measured the temperature rise in heating with the furnace running. The Output BTU is specified at 63000 Btu/hr, I did not measure this, and my temp rise was 47 deg (measured return air boot to plenum delta T) I then used CFM=BTU/hr divided by temp rise times 1.085.

The unit is rated at 2.5 ton (the 30 in the part number TWR030C)

What can cause a low High side pressure and a high low side pressure in cooling mode, in a heat pump, and cause very low btu/hr output in heating mode?

What things would check, in what order, and how?

Thanks, Dave

Wide open metering device or stuck reversing valve.

Everyone, Thanks for the info, Any tips on how to best check the check valve(s) and the reversing valve?

Yes, pick up the yellow pages and look under "heating and cooling service" and call a qualified tech.

I am not HVAC person however if system is properly install when you change you Thermostat from cooling to heating that should automatically make switch, checking system that is something ales call your local service person as Oscar already tall you so from Dido

"AKS" wrote

Then STFU and let someone else answer the questions, you mental midget! Do you post in alt.airline pilots and dispense advice about flying commercial jets when you don't have a pilot's license?????? Like I said b4, you are a special brand of stupid!

Holly friggin Toledo. Why dont you go give free advice on spelling? Oops! Thats right. You cant do that either. Bubba

Bubba wrote

Careful Bubba....you'll just upset Dildo's friends like Gofishlips, Al Moron, Bob Piet, and Nooner, and then what will you do???Huh?? Your life will be ruined, like mine !! You'll no longer be accepted by the "Inbreds of the South Society", Oh, the horror, the horror!!! ROTFLMAO!!!!

At least you still have your Minion card. Never leave home without it.

C'mon. Think back. Exactly when has "acceptance" been my main goal in life? Bubba :-)

It seems to me that spelling dose not worry those who are asking for advise But only those scam artiest or those who think they are pros. You know I really enjoy this it is better then watch one eye Munster (TV)

I L o v e it Have nice weekend Dido say that

Yes, Dido did say that. Now all we have to do is figure out exactly what the fucquer it is Dido said. Bubba