Diagnose this: bad reversing valve or undersized unit?

[rifter1]

Symptoms: 2-speed heat pump doesn't heat well in winter and doesn't cool well in summer.

I had two different guys give me a diagnosis on this.

the first guy diagnoses a bad reversing valve.
the second guy diagnoses an undersized unit.

So I went out to see for myself.

What do you think.

[ISOTHERMAL]

looks like the installers didn't run the proper stat wire to start with, and the techs need to look a little closer. I wonder how they came up with their diagnoses?? Did you tell them what you found?

[jddilligaff37]

not only did they not wire in y2 but also the white wire is what i would think to be w1 if this is correct when unit goes into defrost your electric back up does no receive the signal to energize your back up heat blowing cold air
installers need to RTFM . NOT ENOUGH CONDUCTORS I only run 18/8 on any hp install i do and 18/3 on ac units two wire for od t-stats is this a goodman or amana unit?

[kpsheets0580]

Assuming the reversing valve is energized for cooling when Y2 makes in heat it would actually be cooling instead of heating. Then in the summer it would only cool once Y2 is made.

[beachtech]

looks like i wouldn't post this about my techs i would deff have to talk with them abut thier diagnostic skills or send tham packing ouch!! three call to find this. should always check behind installers during start up or first waranty call!!!

[rifter1]

It's ICP.
Althought some of the Carrier units (50ZPA, ZHA... come to mind...) also have this pink wire as Y2. The reversing valve is the orange unit wire, which is of course wired with the white wire to the O terminal in the unit. Lazy.

[nubbin]

I would go into detail on one hp that does not cool after fan coil control board changed and 'O' is connected to Oh Oh !! but the owner may have helped.