Expansion Valve Question

Livewire78

I was asked to install a split system that a owner purchased on his own and he had bought the air handler back before R-22 was being phased out. A few months later he bought the condensor which was a 410a unit. At the place of purchase they sent him with an TXV kit that is supposed to convert the 22 evaporator coil to adapt to the 410a. Well everything was going as planned until I opened the box to the txv and I think i'm shorted some parts. The txv body was in there along with that piece that get brazed in so that the txv line hooks up to . but there were no other sweat on fittings to adapt to the txv body. On the evaporator end on the txv there is a female compression fitting, but nothing to screw on to the a coil. And on the other end of the txv body there is a male fitting . Should there have been another end for that in the box that you sweat on the liquid line to attach to that male fitting on the txv?. I guess what I'm asking is am I missing to sweat on fittings?

beenthere

This is probably something you shouldn't be doing.

But. The female end of the TXV screws fast to the male end of the piston holder. After you remove the piston.

The male part your referring to, is the external equalizer, that must be tapped into the suction manifold, or line. Preferably inside the evap coil cabinet.

Is the coil a match to the outdoor unit. Or is it a mismatch system. Just because the coil is rated at the same tonnage as the condenser, doesn't mean its a matched system.

Livewire78

The system is a NUTONE and the expansion valve is a Danfoss, both are 4 ton units. I have all wires ran and outside brazed up. All I like is hooking up this txv. I just need to know if I have been shorted the 2 sweat on fittings. I hooked a similar unit up the other day and had to take the original valve off of the discharge line and add a slip on piece with the compression nut, so that I could braze the line to the to the coil. But the expansion valve itself was already pre mounted inside on the coil. but this one came seperately. I've hooked up a few txv's in the past but this confuses me. Unfortunatly I don't have the model number of the txv with me. it is on the job site.

beenthere

It should go right on the piston holder. If not, then you need to get the tail piece. It is not a standard with all TXV's. That TXV may be made as a replacement TXV, and not an OEM TXV.
Nutone is a Nordyne unit.

If they aren't both Nordyne units. Then its a mismatch system.

You can get the install manual for that coil from your local Nordyne distributor. Or Nordyne's contractor's website.

Livewire78

they are both nutone

Livewire78

the txv kit was supposed to be specifically made to convert the R-22 coil to accept the 410A condensor system. So if I get the tailpiece can on the other side where the lineset comes in can I just flare the liquid line and put a flare nut on it the same size as the male end of the txv?

beenthere

No, its not really a flare fitting on the TXV. Its made for a teflon seal.