Nitrogen testing

[joemach]

I have had thus question for a while and never got around to ask anyone.

On a system with a hard lockout TXV (I think that is what it is called), when putting nitrogen in a system to leak test through the liquid line, the low side stops at around 200 psi. Should I then open the suction side on the gauges to equalize the pressure so I have 400 psi on both sides? This would be for a 410a heat pump? Or an I going to hurt the TXV?

[pecmsg]

Raise the pressures equally. Avoid putting too much pressure on one side or the other.

This also applies to valve plates, Scroll check valves everything.

[joemach]

Raise the pressures equally. Avoid putting too much pressure on one side or the other.

This also applies to valve plates, Scroll check valves everything.

OK. Thanks.

[Jackshvac6]

Open both your gauges all the way and turn on the nitrogen tank.

[AIRCON8]

i also open bot gauges all the way and let the nitrogen flow in slowly, but not going up to 400 PSI
i stop at 250

[pecmsg]

i also open bot gauges all the way and let the nitrogen flow in slowly, but not going up to 400 PSI
i stop at 250

R410A systems need much higher test pressure

600%’s

[AIRCON8]

nope i'm not go that high LOL
250 is the limit period

[VTP99]

What if your leak doesn't show up till 300# ?

[pecmsg]

nope i'm not go that high LOL
250 is the limit period

What’s the high pressure limit on that System?

What’s the Test Pressure on that system?

[AIRCON8]

i do residential up to 5 tons
pressure switches txv coils and compressor valve
no need to go to 600 psi
not me

[AIRCON8]

What’s the high pressure limit on that System?

What’s the Test Pressure on that system?

don't know i was just answering to a guy here

[jbhenergy]

i do residential up to 5 tons
pressure switches txv coils and compressor valve
no need to go to 600 psi
not me

Discharge at the compressor is going to be over 400 psi on a 410a unit.

Just saying.


Sent from my iPhone using Tapatalk

[beenthere]

When its a heat pump. Put the nitrogen in through the vapor side. The TXV is only hard shut off in cooling mode. It will still let nitrogen flow from the vapor side to the liquid line.

[pecmsg]

i do residential up to 5 tons
pressure switches txv coils and compressor valve
no need to go to 600 psi
not me

Whats your concern?

See Step 18:
https://portal.fujitsugeneral.com/fi...ll%20Guide.pdf

[HAWK71]

I was trying to find a leak on a 3 head mini split. Finally found it in a flair fitting. It took 400 psi to make it bubble. I left it with 200 psi for 2 days with no change

[VTP99]

I was trying to find a leak on a 3 head mini split. Finally found it in a flair fitting. It took 400 psi to make it bubble. I left it with 200 psi for 2 days with no change

Case in point.

[AIRCON8]

I was trying to find a leak on a 3 head mini split. Finally found it in a flair fitting. It took 400 psi to make it bubble. I left it with 200 psi for 2 days with no change

Nope i'm not going there
period LOL
400 psi too much it will leak at 200 and with a good leak detector you'll find it.

[rider77]

Nope i'm not going there
period LOL
400 psi too much it will leak at 200 and with a good leak detector you'll find it.

No, not really.
I’ve seen many systems where the leak only showed up at a higher pressure, say over 350-400 PSI.
Most minis and all VRF now require ~600 PSI standing presssure for 24 hours.

[hvacvegas]

No, not really.
I’ve seen many systems where the leak only showed up at a higher pressure, say over 350-400 PSI.
Most minis and all VRF now require ~600 PSI standing presssure for 24 hours.

Agreed, and its not even recent.
I remember reading about it for fujitsu 10 years ago.

[AIRCON8]

everybody talking about mini split and VRF
can you imagine 600 psi on a York micro channel coil ?
they leak just if you look at them LOL