Where does the refrigerant live when the system is off?

[pwned]

Say you have a 24,000 BTU/7kW PTAC
When the unit is off, where does most of refrigerant mass live?

[Grizzly]

I have never heard of refrigerant being referred to as a Living component.
Where is goes to "sleep" depends upon the system design.
Usually the greater mass would be on the H.P. Side because as a medium it is in liquid form.
But then again there are flooded evap systems where the opposite prevails.
The refrigerant will naturally migrate to the low pressure side.
It really depends upon the system design as to where the bulk ends up!
Grizzly.

[chemi-cool]

Refrigerant will migrate to colder point > evaporator.

If the unit equipped with a TXV with MOP, some of it will be in the evaporator up to the rated pressure.

If a SV is in use, than over 95 % will be in the condenser and liquid receiver.

[frank]

Refrigerant will migrate to colder point > evaporator.

Hello Chemi
Surely, if the ambient is colder than the evaporator, the fridge gas will accumulate in the outdoor unit ( compressor) hence the need for crankcase heaters
I'm thinking here of evaporators such as walk in coolers or AC

[chemi-cool]

Hello Chemi
Surely, if the ambient is colder than the evaporator, the fridge gas will accumulate in the outdoor unit ( compressor) hence the need for crankcase heaters
I'm thinking here of evaporators such as walk in coolers or AC

Well.... not really, The condenser and compressor are usually hotter than the evaporator.

AC in heating mode, yes.

By the way, can you spare me a day in November?

[Grizzly]

Well.... not really, The condenser and compressor are usually hotter than the evaporator.

AC in heating mode, yes.

By the way, can you spare me a day in November?

Sorry my friend.
But Frank Has a point. Here in the UK and many other northern hemisphere countries.
In the winter the outside units ( Condenser / Condensing Unit) can become colder than the indoor ones.
Therefore these would be at a lower Pressure or Temperature (one and the same!).
In this situation guess where the refrigerant migrates?
So many factors dictate where the refrigerant ends up!

Surely to answer the original question where the bulk of the refrigerant lives.
could depend upon system design and the operating conditions?
Grizzly

[Brian_UK]

Simple answer, included above, is that it will sit in the coldest place that it can get to.

[mikeref]

Hi PWNED, chemi and frank are right in the example you've given, it is a different story for commercial and industrial applications though. OFF: switched off- cycled off?

[pwned]

Well, I was asking where the bulk of refrigerant is stored, when the system is turned off, allowed to stabilize and temperature is fully equalized.

[frank]

By the way, can you spare me a day in November?

Certainly can my friend

[Brian_UK]

Well, I was asking where the bulk of refrigerant is stored, when the system is turned off, allowed to stabilize and temperature is fully equalized.

As with most small systems, things like your PTAC, the refrigerant will be everywhere when everything is at the same temperature.

The liquid will be at the bottom with vapour above it.

[Eeram]

When a system is shut off, the refrigerant will try to "live" in the coldest point, the evaporator.

If the condenser is colder than the evaporator, the refrigerant will move to the condenser. The same applies when the compressor is cooler than the rest of the system.

If the entire system is at the same temperature, refrigerant will tend to "live" with the oil. Liquid will sit in the compressor!

Use crankcase heaters and good pumpdown with solenoid valve in the liquid line on off cycle.

[Goober]

As with most small systems, things like your PTAC, the refrigerant will be everywhere when everything is at the same temperature.

The liquid will be at the bottom with vapour above it.

Mmmm....the refrigerant will be everywhere??? like and all seeing greater being, spanning different parralel universes, able to span the time space continuim and travel through the fabric of life itself....Sorry couldn't resist..

[Brian_UK]

As with most small systems, things like your PTAC, the refrigerant will be everywhere when everything is at the same temperature.

The liquid will be at the bottom with vapour above it.

Mmmm....the refrigerant will be everywhere??? like and all seeing greater being, spanning different parralel universes, able to span the time space continuim and travel through the fabric of life itself....Sorry couldn't resist..

Sorry, you must try harder next time.