ok what is it?

[jtstuart]

Im working on a RUUD Model #UPKA036JAZ. in heat mode it kick the high pressure swith. The head pressure is 325psi and the suction pressure is 60psi. i checked both coils both fan motors and capacitors, everything is clean and ruuning smooth. Compressor RLA 14.1 amps outdoor fan 1.3 amps. Everything seems ok, however I ran out of light before i could check temp drops. would you suspect the 4way valve or TEV blockage? I have a buddy who's had the same issue's on the same unit and switched it out. Im going back today around 4 and going to check temp drop across the 4 way, but was wondering if any of you have seen this issue with a ruud HP and what you did to solve it.

[dandyme]

what's the discharge pressure?

what psi is switch rated for?

22 or 410?

[jtstuart]

its an R22 system Switch is rated for 350psi and the discharge temp at the compressor was 105 degrees.

[mikeybow]

What happened when you engaged defrost or cooling mode?

[keeplearnin]

possibly non condensables. Or another restriction,

[bmathews]

While I have no idea if this is the answer. A buddy of mine installs Ruud and had this problem a few years ago. He switched out the defrost board and as far as I know the problem went away. At least we never talked about it anymore after he did that.

[jtstuart]

mmm things to ponder! I would like to tear into this and see if I can fix it, but on the other hand this unit is 16 year old and the customer may replace the outdoor unit.

[chrisnorris]

Restricted/ collapsed return air duct?

I don't think I would suspect the reversing valve. If it leaked I think you would have lower head /high suction pressure.

Dirty filters inside the house?
I say this because last night I was on a 90% gas furnace that was tripping on high-limit.
The air filter in the garage at the air handler was clean, and the homeowner informs me he washes it every month.
I go inside the house to start taking a temp-rise. I glance up at the return grill and find a dirty filter there. Homeowner says "oh, I forgot about that".

I've ran into heat pumps that had nonconsensibles in the system. Ran fine in A/C, but tripped the hi-pressure cutout in heating due to the smaller indoor coil.

But, if it was non-consensibles, that would mean there's been air in the system before you arrived. Since it's mid-winter, (assuming nobody else has worked on it) wouldn't the high pressure cutout started opening earlier at the beginning of winter when they first started running it in heat?
Just a thought. Keep us posted.

[mlc1955]

I think I would rule out low airflow across the indoor coil because if that was driving the high up usually the suction would go up also. Generally a refrigerant flow restriction makes the head go go up and suction go down so i would look at the outdoor txv.

[Tjune54]

Most R22 units have a control that trips at 400 to 410 psig. You may have a bad control or if yourchecking at the liquid line valve move to the discharge between the compressor and reversing valve where the control is attached.

[SBKold]

You are severely overcharged. Id recommend.recovering charge - see how much is in there.

Weigh in proper amount and diagnose from there.

[kyjourneyman]

I believe you may be over charged also. what is the outside temp when you was checking if the temp outside. 60psi may be high suction if you was so cold you should have been running 20psi. What was the subcooing and superheat temp and did you turn on the heaters and do a temp rise to get you cfm's. you should have about a 150 to 175 temp on discharge line if not then you may be overcharged causing flood back which is dropping our temp

[John Markl]

Sounds overcharged.

I don't want to start a pissing contest over how to (or if you can) charge a heat pump in the winter, but I typically look for 20-30 degrees over indoor ambient on the high side, and somewhere around 20 degrees under outdoor ambient on heat pump mode.

[jtstuart]

ding ding ding!!! It was overharged!! it was throwing me off because when the pressures normalized i had 98psig and to the pt chart 96.2 but when I weighed it out i had about 3 lbs to much. thanks for the insight!

[jpsmith1cm]

ding ding ding!!! It was overharged!! it was throwing me off because when the pressures normalized i had 98psig and to the pt chart 96.2 but when I weighed it out i had about 3 lbs to much. thanks for the insight!

Why would the standing pressure be any different on an overcharged system, a mildly undercharged system and a normally charged one?

[joemach]

Sounds overcharged.

I don't want to start a pissing contest over how to (or if you can) charge a heat pump in the winter, but I typically look for 20-30 degrees over indoor ambient on the high side, and somewhere around 20 degrees under outdoor ambient on heat pump mode.

John,

Could you explain that a little further?

I have a hard time getting my head around how to get a heat pump properly charged at 20°F. I am looking for all the ideas I can get.

[pony]

this post give me a idea dont depend on weight in freon sometime,cause it is realy not that reliable,best way is check the SC and SH,just how i feel,,thanks

[pony]

jtstuart,that still wont explain why hp switch cut it off,cause 325 discharge pressure is not to high?