# Mini split superheat/subcooling



## Bitters (May 28, 2014)

No need to take humidity reading. The testo 550 has every thing you need.


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## yuri (Nov 29, 2008)

mini splits are a weighed in/critical charge according to the length of copper and the manufacturers chart not like a resi unit in a furnace or air handler.


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## Doorguru (Feb 20, 2015)

Bitters said:


> No need to take humidity reading. The testo 550 has every thing you need.


 Thanks. What parameters am I interested in on the 550 and what do I compare them to?


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## Doorguru (Feb 20, 2015)

yuri said:


> mini splits are a weighed in/critical charge according to the length of copper and the manufacturers chart not like a resi unit in a furnace or air handler.


 
I know I can reclaim and recharge it by weight, but my unit is already charged. I just want to verify it has the right amount of R410.


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## yuri (Nov 29, 2008)

I use the chart that comes with it from the install manual and the length of copper and then it gives you the suction pressure at the outdoor temp. No need for superheat etc. Not sure if all brands do it that way.


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## beenthere (Oct 11, 2008)

Doorguru said:


> I know I can reclaim and recharge it by weight, but my unit is already charged. I just want to verify it has the right amount of R410.


Can only verify correct charge on a mini split by removing and weighing it. They are not charged by Sh or SC, nor can their charge be checked by using Sh or SC.


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## roughneck (Nov 28, 2014)

Minis are very different then other units, especially inverter drive equipment. 
No SH/SC on these units.


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## Doorguru (Feb 20, 2015)

Thanks for the help guys. :thumbsup:


How about on a conventional 4 ton R410 unit? 

Would a Testo 605-H2 unit, along with a charging chart, and my Testo 550 be the ticket to calculate and check superheat/subcooling ?


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## beenthere (Oct 11, 2008)

On fixed metering devices, yes it will work fine for SH. Won't tell you what the SC should be most of the time.


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