TXV problem

[local 392]

Well I think I can say i've seen it all. Worked on a 20 ton train split system today, Found a bad txv valve a week or so back. Scheduled the repair, go and recover the refrigerant. remove the bad power head (bolt together) and to my suprise the gage was gone! The evap coil has 4 expansion valves with hot gas by pass, so this was keeping it running. First time for this one.

[Six]

The "GAGE" ?

Im guessing is was shut so HGBP kept it running

[local 392]

My bad CAGE. The good thing about the mind going is you don't know it.

[valdelocc]

I read it twice and I still dont get it, cage,gage??? was it gone? what are you talking about?

[allstar08]

gauge?
hot gas kept it running. Trane used to put high temp limits on the discharge line of their split systems.

[toptech]

I read it twice and I still dont get it, cage,gage??? was it gone? what are you talking about?

Think of it as the "cartridge" on a sporlan valve.
Each cage has a tonnage rating for a universal valve body.

[jhd1234]

Alco take apart TXV's [T series] have selectable cages inside. The cage has the port, superheat spring, and adjustmnet all in one assembly. Trane used to use them a lot. Check them out at Emerson's website. Cage missing- I never encountered that! Just when you think you've seen it all. he he

[local 392]

Unit has two 10 ton scroll compressors in tandom niether with discharge limits. I guess the only thing that kept it from distroying itself is feeding enough hot gas into the evaporator to stop it from flooding back to the compressor. The bad thing is this is not the only problem this unit had. The second stage compressor shuts off, cutting capacity down to 10 tons. No solenoid valve to shut down any of the expansion valves. Now one 10 ton compressor is trying to feed 4 five ton valves. Unit designed this way. I guess it works this way just not very well. Now it has 4 new expansion valves,a new hot gas by pass valve, liquid line solenoid valve to isolate two of the txv valves, and a solenoid valve to shut off the hot gas to that set of valves. I checked the operation of it today, working better than it has ever according to the customer.