Rheem heat pump problem

[searstech3]

I have a 4 ton Rheem heat pump that I'm looking at for a friend. It cools good, and it heats good. The complaint is that he has to reset the high pressure switch on very cold days.

I slap the gauges on it in cooling and get 40 suction & 150 head on a 75* day. Evap is clean, blower etc. . I tried to add a little gas , no pressure changes...So I tried it in heating mode. Switched my gauges ,fired it up and now really scratching my head ,120 suction ,125 head.

In cooling mode the center tube on reversing valve back to compressor was cool and right tube was cool . Only 4* temp difference. In heating mode the same two tubes were warm. That don't seem right to me? Should it be the tube on left now for heat. RLA for comp 29.1 It was pulling 14.3 in both modes. Is my RV bad ? Or is this scroll compressor kicking my butt ? Also flutter on high side gauge in heat mode only. Heat pumps a rare for me to see.

[jacob perkins]

Originally posted by searstech3
Rheem heat pump It cools good, and it heats good.

The high pressure switch opens at 450psig,I think.
maybe bad switch, (or blocked meterdevice,kinked line....)

Sounds undercharged,but cant know without a suction line temp.40 is too low.

Rev.valve sounds good.

[paddyhvac]

you might check your indoor coil and filters also return sizes these things can cause high pres in the heat cycle as well as if it is an electric airhandler make sure heating element are not all on when in w1 and that there is outdoor stat that cuts hp off below 30 degrees when aux is called for only 1 or 2 heating elements should be on if it is a duel fuel system that is a whole different ball game

[jacob perkins]

....or a mis-matched coil and heatpump....

[airconman]

do you have enough air flow on inside coil for one thing?

[conair]

many things to look at first were are gauges connected and what kind of metering device is insde and out side?
does this system matched?
post more info?

[leander]

The pressures are too low. Also the suction line to the compressor should never be warm. It sounds like the compressor was not running thereby equalizing the high & low pressures & that would also explain why the warm suction line between the reversing valve and the compressor.

[docholiday]

Sounds like a hanging reversing valve to me.

[Swampfox]

Staying in defrost too long maybe, I cant see a stuck RV or one leaking by causing the HP switch to trip, that would make the head pressure lower and the suction higher, you may have more than one problem

[filterchanger]

expansion valve in the outdoor unit is bad or the bulb is off not touching pipe. just a guess!

[jacob perkins]

Originally posted by searstech3
the same two tubes were warm.That don't seem right to me?
No, it aint right.
Should it be the tube on left now for heat.
On the side with three lines (bottom) you want the middle and one side or the other to be cool.On the side with one line (top) you want it and one of the bottom lines to be hot.
Is my RV bad ?

Something's wrong. Let us know how you solved it.

[docholiday]

Originally posted by swampfox
Staying in defrost too long maybe, I cant see a stuck RV or one leaking by causing the HP switch to trip, that would make the head pressure lower and the suction higher, you may have more than one problem

He said that when he switched it to heating his suction was 120 and head 125. Thats high suction and low head, isnt it?

[billva]

make sure your low side is attached to the common suction port.
put the system into a forced defrost and see what happens to the high side(liquid line). you may have a clogged or immovable accuator.

good luck

[obac]

I HAVE RUN INTO THIS PROBLEM MYSELF. I INSTALLED 13 13SEER RHEEM SYSTEMS THIS YEAR. IF YOU DO NOT HAVE AT LEAST 24 INCHES OF STRAIGHT DUCT COMING OUT OF THE AIR HANDLER, IF IT IS A RHEEM AIR HANDLER, IT WILL GO OFF ON HIGH PRESSURE. IT IS NOT GETTING ENOUGH AIR FLOW. THIS CAME FROM THE RHEEM TECH REP IN OUR AREA. THE ONLY THING YOU CAN DO IS BLEED OFF UNTIL YOU GET ABOUT 250PSI ON HIGH SIDE IN THE HEAT MODE. OTHERWISE YOU MUST ADD SUPPLY DUCT AT THE AIR HANDLER. BEEN THERE, DONE IT.

[billva]

you don't really go by a 250 psi for all outdoor temps., do you?

please, say it aint so.

[docholiday]

And here I though the installation instructions were just a kneepad full of information just to make an installers life miserable by printing information to make the system run correctly.

[obac]

IT IS NOT SO. SORRY FOR GIVING THE WRONG INFO. GO BY THE CHARGING CHART ON THE COVER. 250 PSI WAS JUST A REFERANCE POINT.

[vettech]

[QUOTE]Originally posted by searstech3
I slap the gauges on it in cooling and get 40 suction & 150 head on a 75* day. Evap is clean, blower etc. . I tried to add a little gas , no pressure changes..

You didn't add enough if the pressures didn't change. Add refrigerant until you see a change.Is the blower running? Post more info if you want help



.So I tried it in heating mode. Switched my gauges ,fired it up and now really scratching my head ,120 suction ,125 head.

What guage port are you on? You are on the wrong suction port if your amp draw is the same in both modes.Need more info.

[qssfl]

First of all..If you had to switch your gauges between heating/cooling modes then obviously your suction hose was not on the correct suction port. That would be the third port on the machine you didn't see...all rheem heat pumps have it..

If your head pressure switch is tripping in heating mode... it could be one of the following but not limited to:

1. bad powerhead on outdoor txv or debris in the outdoor metering device.

2. defective defrost termination thermostat or defrost control board

3. dirty indoor coils or indoor airflow problem ie..indoor blower motor not up to speed..(due tothe fact you have a 40# suction in cooling mode)or possibly indoor motor going out on overload in heating mode

This is where I would start....

Let us know what happens....

I hate when someone asks for help and never again replies....

[docholiday]

I'd skip 1 and 2 until you verified 3. Poor ductwork should be added to it, then, if my airflow was correct, I would verify an equipment match, my line size, length and vertical seperation are within the guidelines in the manual. Then if all that is ok you should pull the refrigerant, tripple evacuate (break with nitrogen) and weigh the charge back in. Then if you still have problems you can begin the parts guessing.