R410A Charging - Charge as Liquid, service port on Gas only?

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R410A Charging - Charge as Liquid, service port on Gas only?

Postby verylongusername » Wed Aug 03, 2016 2:55 am

Working through installation of my first multi-zone ductless (with my luck, happened to be Klimaire KSIM330-H219 which seems to be the least / worst documented...).

How do you add refrigerant on a ductless system? I know I must use liquid / low pressure side, but there's no service port. Trying to charge on gas / high pressure return line is pointless due to higher pressure. However, it appears that ALL ductless systems have service port on gas side only... What am I missing?...

It makes sense for multi-zone units to have service ports on high side (to validate functionality of each individual indoor unit). But is there a liquid side service port somewhere? Should there be one, at least, for charging?...
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- R410A Charging - Charge as Liquid, service port on Gas o

Postby Freon » Wed Aug 03, 2016 2:11 pm

I do not know anything specifically about R410a. However since a compressor is designed to compress the refrigerant in its gaseous state upon return from the evaporator coil, I sincerely doubt you would ever want to charge with liquid directly. And since you will not be able to charge on the high side port(s), I suspect the low pressure port may be buried inside the unit but I do not know this for a fact.

Check to see if there is another port at the compressor. Check the pressure, it may be the low side. Usually you use the high side when you first charge a system by weighing the correct amount of charge and adding is as liquid with the compressor off.
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