convert R22 evap coil to R410a - need TXV

raylo32 · 08-31-2011, 06:45 PM

I have a new Carrier 3 ton R22 evap coil I bought a few years ago and haven't used. My current R22 system has a microleak but hasn't gotten any worse so I never installed the thing. It has a factory installed R22 TXV.

I might want to use this coil on a new R410a system if I can find a TXV to fit it. It has a threaded connection on the distributor end and the EQ line is brazed. I am pretty sure I can remove the thing and can rebraze the new EQ line. But I am not sure about the threaded connection to the manifold side. Is that standard so that a Goodman or whatever will fit or do I need to find a genuine Carrier/Bryant part?

Here is the distributor side:

Not sure how the 3/8 liquid line is attached into the front of the TXV body either. Does that piece thread in/out? It doesn't look like it was brazed in.

Master of Cold · 08-31-2011, 06:54 PM

I would come off of the $40 and buy a new valve.

raylo32 · 08-31-2011, 07:03 PM

I am looking to buy a new TXV. Just need to know what will fit... do I need a genuine Carrier, that I having trouble finding, or are these threaded connections standard so a Goodman TXV or other brand will fit up to the distributor fitting?

raylo32 · 09-01-2011, 10:08 AM

One more try on this with a simplified question: Can anyone identify the 3 ton Carrier/Bryant R410a TXV part number (and sources to purchase) that will fit up to the flare distributor connector on this R22 coil? ...or an alternative TXV that will fit up, if any.

Coil is a previously unused CNRVP3617ATA

raylo32 · 09-01-2011, 12:51 PM

I beat on this some more and found the part #. Here it is in case anyone else needs it: 331709-755. I can't find a picture of it to see if it has the same flare connection on the distributor side as my current R22 TXV.

Done That · 09-02-2011, 08:33 AM

Those threaded fittings on the TEV outlet are typically either Aeroquip or Chatleff and utilize a white teflon gasket for sealing. Aeroquip and Chatleff are not interchangeable, and OEM's used both 1/2" and 5/8" versions. Sometimes you can find a MFG mark stamped into the brass part to help ID the type.

You might want to check Johnstone Supply or others for generic TEV once you determine exactly what fitting type the original had.

raylo32 · 09-02-2011, 09:12 AM

Thanks for the info DT.

I called Carrier and they referred me to the local distributor who supposedly has 6 of these in stock. I will drive by and have a look to see if it matches. I believe that the Carrier C(AorN)(RorP) coils are pretty much the same except for the TXV so hopefully the one for the CNPVP3617 will plug and play in my CNRVP3617, at least on the TXV outlet. We'll see....

raylo32 · 09-02-2011, 12:31 PM

Got the new TXV. Looks like a direct fit except it came with one of those handy dandy schrader connections on the EQ line. But of course my old coil doesn't have that. That would be far too easy. The EQ line is just brazed into the vapor line.

Never done this before. I am guessing the easiest way would be to cut off the schrader connector on the new TXV, then take my torch and soften up the braze and pull out the old line, then braze the new one in its place. Or would it be easier to cut, crimp, and braze shut the old one then braze the new one in a new 1/8" hole?

Done That · 09-02-2011, 01:51 PM

I have no experience on brazing so I won't attempt an answer on that. I can tell you the TEV OEMs cut the end of the EE tube at an angle, not straight across, as a bit of a safety net in case someone over inserts it and it ends up getting blocked by bottoming out on the inside of the suction line.

raylo32 · 09-02-2011, 02:41 PM

Excellent tip. I know to try to stop it about half way thru but that is a nice fail safe. Thanks.

I can braze lines and such but never tried to pull one of those EQ lines out.

Quote:

Originally Posted by Done That

I have no experience on brazing so I won't attempt an answer on that. I can tell you the TEV OEMs cut the end of the EE tube at an angle, not straight across, as a bit of a safety net in case someone over inserts it and it ends up getting blocked by bottoming out on the inside of the suction line.

Master of Cold · 09-03-2011, 09:42 AM

You have to heat the suction line, not the eq line when removing and installing the new one.

raylo32 · 09-03-2011, 09:55 AM

Sounds good. I was figuring I might have to keep the direct flame off that little line for fear of melting... but I am using just an oxy-air torch so blowing it away is less likely. Doing this on the bench with a brand new coil so easier than what you guys do in the field.

I'm glad I will be able to use this coil for my eventual upgrade. I'd rather not try to hawk it on e-bay or toss it. Don't like wasting perfectly good stuff.

Quote:

Originally Posted by Master of Cold

You have to heat the suction line, not the eq line when removing and installing the new one.

AirstarFilters · 09-09-2011, 12:02 PM

Push in some Cliplight Super Seal product and call it a day.

Master of Cold · 09-09-2011, 06:58 PM

Superseal. A great product for clogging driers, cap tubes and txv's.

AirstarFilters · 09-09-2011, 07:15 PM

Yet to experience. Lots if nay saying contractors , zero home or business owners. Used in automotive industry with smaller orifices for tears.