System Pumpdown without closing the suction line valve?

[Jbjorgaard]

Greetings,

I've been searching through google for quite sometime now to try and find the answer to this question.

My evap coil had been icing up so we called out a tech. He determined that the refrigerant level was adequate and that it was simply the TXV that had broken. He proceeded to pump down the system and store the refigerant in the condenser, however he only closed the liquid line and left the suction line open. He explained to my wife that we would be able to replace the TXV w/o losing any refridgerant that way. (I was at work when he was at the house)

From what I understand you must close the liquid line, pump it down then close the suction line.

I went to remove the TXV and there is still considerable residual pressure when I went to unscrew the flowrator distributor assembly. I was expecting some, but after about a minute of bleeding the system there was no noticeable drop in the rate of release so I closed it back up.

So the big question I guess is without closing the suction line valve is it possible to trap the refridgerant in the condenser coil?

This is on a Lennox heat pump which is roughly 10 years old.

Thanks in advance

[Magoo]

In laymans terms, system gas can bleed back through the compressor to the low side/evaporator if compressor suction stop valve is not closed. Get the tech., back and pump out again then close suction stop vav on compresor, after repairs pressure test and leak test system then vacuum/ evacuate the low side before re-instating system.

[Emmett]

(1) Why are you removing the txv? In theory the compressor valves will hold a vacuum and you could perform this work without closing the valve, however in practice you never find a 10 year old compressor or newer for that matter that will hold a vacuum for long. Do not open the system, as Magoo stated you should get a technician with the proper tools and training to provide this service.