.71 Piston ???

[Robhenry]

Ive got a 3 ton older 10 seer trane and a goodman 3 ton coil. With the .71 piston size my evap seems to be starving with only 3or 4 inches on bottom of A coil cold. I think the a coil needs a bigger size orifice. any suggestion on what size to exchange piston with to increase coil capacity. Suction line not getting as cool as needed at the service ports.

[basshound71]

what does the condenser call for

[Robhenry]

Does the data on nameplate offer any info? manual is not avail. Whats your experience

[basshound71]

It may say but I doubt it. Go to manufactur and give model and serial.

[basshound71]

superheat, subcooling

[Robhenry]

Gotcha, time to pull out the fieldpiece.

[stephy]

Not to be a stickler about math...

But if you have to call tech support, it is a .071..........

Little bitty hole..

[catmanacman]

a txv and start kit

[Glennhvac]

Hmmmm the first thing that should come to mind is that that coil did not suddenly have the wrong orifice. Has it not worked in all the years it has been installed? Plugged cap tubes?

[basshound71]

a txv and start kit

or that

[Robhenry]

Thanks for the reply, I have been thinking about this. Possibly a clogged or partially clogged dryer near the compressor. My next step will be to add a txv kit. Going to check the price today.

[SBKold]

The piston size is listed on outdoor unit data plate.

I didnt believe I had missed that all these years....but it is there!

10seer 3ton Trane is likely a .069-.071 though.

[Robhenry]

I'm gonna look closer myself. thank you for your reply.