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WhosAce
25-01-2021, 08:25 PM
Hi,
wondering if this is theoretically possible:

Have a P200 outdoor unit that has a max indoor capacity of 300

I wish to connect 2 groups each of 250 indoor units (total 500) but ONLY having one group available at a time.

Questions:
1) Does error 7100 (capacity error) Stop the system functioning or is it just a warning?

2) Could I trick the outdoor unit by setting dip switches to that of a P350 giving a max capacity of P525

3) remove the M-net's to those not in use while they're not being used?

4) Something else?

Thanks in advance!

frank
25-01-2021, 08:33 PM
How do you know that 50% of the gas charge is contained in each indoor group of 250 each time you isolate i group?

could leave the other group under or over charged.

WhosAce
25-01-2021, 08:42 PM
The pipe and other calcs are all within capacity spec for the P200 unit. I'm assuming the limit of 150% is due to most people expecting 100% capacity from all units simultaneously. I don't ever need that. The requirement is for 200-250 max

WhosAce
26-01-2021, 03:51 PM
OK, changing the capacity on the outdoor unit causes an error and so does disabling the connected capacity setting. Time to get smart.

WhosAce
26-01-2021, 09:27 PM
OK, cracked it I think! By disconnecting the M-net to a group of indoor units DURING outdoor unit start up it ignores the additional indoor units and all seems to operate normally.
I will add a time circuit that disconnects the group via the M-net each time the outdoor unit starts up. Thanks for your help!