Gas and Oil Home Heating Furnaces - Air from Heat Pump is cold, uses aux heat often

I have a Ruud Heat Pump and just had to have the high pressure breaker switch replaced. In order to do the work they had to reclaim the freon and replaced it when work was completed. It was done when the outside temp was around 30 - 35. Since then the Heat Pump has not seemed to be as efficient. It blows much cooler air and has to use aux heat often. A friend told me that it was to cold for them to reclaim the freon when they did the work and probably the freon level is now too low because not all of it was able to be put back in the system. Could this be the problem and would this cause the system to not heat as well? The HAVC firm says the pressures all checked out when they finished the work so it's probably because it's been cold but I know that the system was more efficient before the switch was replaced. It definetly used the aux heat a lot less. Thanks for your help.
Rick

Yes it is very likely that the technician didn't put the correct amount of refrigerant into your heat pump and if that is the case it will not heat as well as it should. It is more difficult to "zero" in on the refrigerant charge of a heat pump in the heating season. It is best in my opinion to weigh in the correct amount of refrigerant. Equipment manufacturers put a heating cycle "check" chart on the unit that is supposed to get you in the ballpark on the charge. Most charts require you to take temperatures of outdoor air (dry and wet bulb) entering the outdoor coil and indoor air temperature (dry bulb)then go to the chart as a reference to obtain certain pressures for the conditions that the system is operating under. Maybe they didn't follow the rules and performed a "seat of the pants" charging procedure and missed. An undercharged heat pump system will tend to ice up on the outdoor coil faster than it normally does and therefore will require more defrosting than normal and when it does go into defrost, it doesn't defrost as well as it should due to the lack of refrigerant, it's a "Catch 22". Like I said before, the best method is to weigh in the correct amount of refrigerant according to the manufacturers specifications. I would call the company back and request to speak with the service manager. Let him know about your concerns and request that he come out and check the unit. If the company is really concerned about pleasing you as a customer, they should send their best tech out to check your system again.

Oh, one more thing. A heat pump loses capacity as the outdoor temperature drops. Did the weather get considerably colder after the repair????? If so, the company may be telling you the truth that the charge is correct and the running time is due to the colder conditions. I personally would still go back out to check the unit to set the customers mind at ease.

Just curious if the indoor coil and blower was checked or cleaned during the high pressure switch replacement. As the indoor coil rejects heat from the system in the heat mode, dirty coils/blowers can cause an increased high side pressure due to slower heat rejection to the indoor airstream, this can, over time cause cycling of the unit on the high pressure cutoff switch, wearing it out prematurely. (I've seen relatively few HP switch failures, often a symptom, rather than a cause) Also, if refrigerant was adjusted in this condition, the charge will almost always be incorrect.I'd wanna know. Good luck.

DrCarrier - thanks for the info and your help. The temperature was colder for a while but has since been warmer and no change in operation, that's why I got concerned. I will call them back and request to talk to service manager as you suggested. I wondered if it may even be a freon leak since they worked on unit. I guess I'll find out when they come out.