Let me give a history:
Have a 3 ton heat pump Ruud system that has had a leaking evap coil that started having a total blockage in condenser unit. This systems has txv at evap and condenser. I decided to replace the evap coil, txv and filter dryer. Hoping that the filter dryer was slammed clogged. In pressure testing my connections, found a big leak in the bottom of the accumulator so I brazed another one of those in..

Pressure tested again and all seemed fine so I pulled a deep vacuum. The same thing started happening. Both suction and liquid line would pull into deep vacuum. I tried putting supco oil in and switching the reversing valve to see if it was sticking or something. It sounded like it was working normally. When I would energize it, would switch to heating mode and got to a high head pressure fast.

In cooling mode the liquid line would frost up and turn cold before pulling down and the suction line would turn cold also. Now since this unit has a txv I would not think it would impact cooling mode but I guess if it is slam shut nothing is happening. Felt the small tube coming from suction to txv and it really did not change at all. Then the U tube, like bypass from txv to distributor would only frost down to where the liquid line come off. Nothing near the distributor area or other tube.

I took the txv bulb off at the condenser unit and placed in ice water and no change. Normally if I have a reversing valve going bad, my pressures tend go more toward equalizing than both pulling down to suction. Any insight in how to narrow this down and prove 100% what the issue is would be great.

Thanks in advance for any help.

Sounds to me like the problem is the outdoor txv. How old is this system? From the amount of repair you have done sounds like it would have been better off getting a new system.

Joshdta,

I agree with you 100% on replacing the unit. It is a 96 so it is not totally an antique yet but is coming close to the end of life cycle.

3 other tech looked at this problem and walked away.

I am doing this for free. The family has a son that has lost a kindey and he is 16. His sister donated one to him and his body is rejecting it and will have to have another.

Needless to say the family stuggles to make it day to day with medical bills etc... So this is on my dime and I am trying to do it right and fix all of the issues and see if I can buy them some time. I just don't have the spare cash right now to buy them a whole new system. Time wise I agree I would come out better off.

And the plus is I will learn from this. In 6 years I have not encountered this issue. I did have a Rheem one time that has a solder ball break loose and caused me to scratch my head for a while.

Thanks for any input.

Ok, so lets see. You replaced the coil and the indoor txv right? Also the accumlator outside. Was there a lot of oil build up in the old accumlator that could have went else where?

When I pressure tested after putting in the new coil is when I found the rusted out accumulator. A couple of ozs of oil at max was in the accumulator. I estimated and put that much back in a deep vacuum when I put refrigerant in.

I agree it does look like the TXV. Now my outdoor TXV should not be used in cooling mode and should allow it to bypass... I do not see any icing around the distributor into the txv but on my liquid line on the by pass tub at the top down to the dryer and out the liquid line frosts up..

When I energize the RV I do feel flow change and sounds normal and do not hear any odd sounds or get any reason it is not working. I also put in supco oil in to help if it was sticking a little.

I have to think it is in or around the TXV as well. Just wanted to get some input from someone that may have already had this or could explain why the valve would be working the way it is. I guess if I is not the TXV I really only have one other thing to change.

Thanks for you help..