My symptoms are similar to one of the member(themayor). My heat pump is a Coleman THE2 unit(19 YEAR OLD)with a 2 year old compressor. Technician cannot adjust the pressure and said he wants to comeback to adjust them for the heating season.Why would a tech comeback to adjust it so I could use it to heat my house?It cools perfectly but when switched to heat for winter it does not heat(FAN RUNS ALL THE TIME). Even at temperature above 40 F.Is this a sign of freon contamination or other devices not fonctionning properly? My electronic filters are clean, coils clean, ducts clean. The DELTA T shows a 2 degree difference and I think it should be a lot more than that. Thanks for your help

 

Id call another hvac tech here for sure. 19 years old 2 year compressor. You can have lots of things here. 4 way valve not working. The TXV valve or a orifice return not working from contamination.Bad drier ?did they use a heat pump drier on it with the new compressor.When was the last time it did work ???? did you have heat before the tech ????

Dont think I would have put a new compressor in a 17 year old heat pump

ED

 

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Thanks for your quick reply. Heres a few answers to your questions, and I'm giving you more information that I should have given in order to help your diagnostic:
• Yes a new drier was put in when the compressor was changed.

• Yes before the tech came I had heat, however the pump went into lock-out often, the large gas line out of the pump and into the A coil were very hot. Then the 240V AC breaker came off and the tech was called.

• His diagnostic was that the compressor was kaput, he changed it as well as the drier, start and run capacitors.
He then recharged the pump after using a vacum pump.

• He then made several tests, including going into defrost by shorting the pins on the board. Would that answer your question about the Reversing Valve?? However no heat test were performed since the outside temperature was around 90F (did not measure the Delta T).

• The final results: the AC was working ok during all summer, but when it was switched to Heat in the fall: Many lock-outs were experienced. Didnt want to damage the pump again, so did not use the pump during the heating season.

• N.B. due to the age of the pump, I'm wondering if I should use the pump only as an Air Conditioner, if this is possible are there any mods can I can do myself? I'm handy with Voltmeters and clamp-on Ampmeter.

• The situation now is: works ok in air conditioning;
Lock-outs in Heating mode, so I have the system in Emergency Heat all the time. The Delta T is only 2 or 3 degrees.

Your input is very welcome and thanks in advance.

 

What is lock out ???? Do you mean it went off on high head. Or did it go off on the klixon.

You say it did run in heat and the big line got hot witch it should. 19 years old you could have a check valve there on the A coil and it dont work right.

As I said before I would get a new tech hvac to look at it.
If it works in AC yes you can run it. But when you go to the EM for heat it cost you about 2/3 more in $$$ than with the heat pump working.

ED

 

ED:
Yes I should get another tech hvac (the fourth one) but the problem with these guys in these parts of the woods is to get one that realy know their stuff. Coleman got a very bad reputation around here for several years and its hard to get a good hvac tech. I approached other firms, and when they find its Coleman, they want nothing to do with it.

In these parts of the wood they use the term "lock-out" instead of "cutoff". In other word, if you get high temperature or high pressure the current sensor gives a signal on the "L" (Pur) which in turn operates the cutoff relay in the furnace/heat pump control box and operates the "cutoff" relay which "locks out" the heat pump and makes the furnace go onto emergency heat. I'm not an hvac tech and dont know too much of its details, but I can read a diagram since I worked designing electronic equipment all my working life (i've been retired for 20 years now).

You may be quite right in suspecting the A coil, since the AC works well and the Heating mode doet not, and the Delta T is non existant for all practical purposes.
Tks for your feedback.

 

Ok then you know how it works for a heatpump. with some relays and valves. WE make the A/C indoor A coil the out side one and the outside coil then the indoor coil for heat.
Thats why I think at the A coil. On AC the liquid freon comes in, in the small line goes off to a gas and gets cold. Goes on back to the compressor in the big line. Now on heat pump we send the hot gas in the big line to the coil for heat in the home and cool down some then back to the coil by the compressor. You said that on start up on heat its hot then goes off on high head. Thats why I still think the A coil could be it in the TXV , Orifice , check valve ,can be it or the out door coil. something is stopping the flow to go on high head in just heat pump.
My papers show L as system monitor switch I see now where you get the lock out from.

ED

 

If it's not an airflow problem it could be overcharged. But whatever made the 1st compressor go out was not cleared up and is probably reaking havoc on the 2nd compressor.

 

If something was wrong with the new compressor why is the pump cooling fine in the summer but when in heating mode it is not warming up and the pump fan keeps running all the time? You said it could be airflow problem or freon charge. Aiflow problem; do you mean that the inside coil should be clean; I have no access panel to have the tech clean it and when one shows up he doesn't feel like messing around with it.Anyway I will call a tech again.

 

When on heat pump it goes off on a high head.
What--- valves the A coil has dirt in it ??? But you say AC is ok . Do you get good air flow then.19 years is the blower clean the blades in the blower wheel there all clean?
I had a unit that went off on high head . It was one that had a check valve on the A coil that didnt work. Wouldnt let the hot gas go back out side to the coil there.

ED