are 410a Handlers R22 Compatible?
I needed an R22, 2.5 Ton air handler replacement, goodman said 410a Model ARUF303016CA was compatible so I installed it w/o TxV-Valve and the results were a disaster!
I have about 120psig (70.0F) on the low side and 200psig (100.0F) on the high side, the registers' are approximately 78.0F.
Suction line gets nice and cold but high side is almost at room temperature,
I checked the condenserr fan, its running how it should and the condenser was cleaned recently.
I tried a temporary airflow restriction (cardboard) on the condenser to see if it would affect the head pressure but it didn't.
How can I improve this???
Do I need to change or remove the piston?
Do I need a TXV Valve?
Wrong piston or possibly no piston at all
.065 piston for r-22 2.5 ton Goodman.
Always check the piston size, use the original piston from the old coil.
I'll be there when I get there and not a minute later
When I do this I prefer a txv. It makes the job faster and easier with little guess work. I've done about 4 in the last month and they work like a top.
Originally Posted by myhvacx
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Superheat???? If you have a negative SH you probably have no orifice and your evap is now a condensor...... :-O. If your SH is low wrong size!
Did you install an appropriate size piston for the outdoor unit, and did you install it in the right direction?
The piston that came in the air handler is NOT appropriate for an R-22 system.
I'm sorry but how could you do this without checking for the correct metering device. Although you would think your wholesaler would give you the correct metering device. The last dry unit I did I didn't get a chance to ask, they asked me if I wanted a piston or txv.
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I would say that even if you used the piston that came equipped in your replacement coil (which likely wouldn't be the correct match), the piston size would be close enough to where you wouldn't be getting THAT kind of operation. Check your match-up and metering device with your supplier. And if that's all okay, then you've got something else major going on. Is this a recip or scroll?
It ain't the piston size that's the problem.
Its either missing or in backwards to get those pressures.
Are you giving us the line temps or the saturation temps because you have virtually no SH or SC?
The best things in life are free but not everyone is willing to pay the price.
I'd guess, there is no piston in that coil.
Thanks for your responses guys, took me a while to come back but I did go back and fix it a couple days ago, it turns out the piston wasnt the right one, it was too big and changing it fixed the issue. TY!
Just the opposite for me-
I ran across just the opposite setup yesterday...Had a 410A Carrier condenser which had been put in some 7-8 years ago. I was out to do a system check, found it iced up. Thawed it out, made sure filter was clean, etc. Set up my gauges, cycled it, saw my suction was at 100 psi, liquid at 305. Was waiting for it to run a bit and had probes set up to check subcooling and superheat, then saw the liquid pressure start going all over the place-as high as 550, then down to 325, then up. My first thought was non-condensibles, then thought-let me check the TXV-maybe it's closing down. Only there was no TXV, the installers used the R-22 coil with a fixed piston. With the same line set.
Now my thought is it should have a TXV, though it has "worked fine till now".
I know this is a long winded post-bear with me.
I'm also wondering if they didn't flush the line set that there could be some mineral oil gumming up at the piston. Or that the POE has broken loose some carbon deposits that could doing the same thing.
There is also no high pressure safety on this unit NOW, which isn't to say it hasn't been removed. I have to say, I primarily work on commercial equipment, and all 410A systems I've seen have HPS, though all residential systems I can think of have as well. I'm not a gambling man, but I'll bet there was a HPS, and it was a repeat offender because of installation procedures- but since they would see half-way decent cooling, it was removed...by the installer...cause they either knew why it was tripping, or didn't care.
Appreciate any thoughts on it-at this point my game plan is new evap with TXV, flush, new drier, and a 250 micron triple evac. And a HPS.
Gotta be tough when you're dumb!