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Slim R410a
18-01-2014, 10:31 AM
Hi,

I need to carry out the following on Monday, any answers would be much appreciated.

Outdoor is a PURY-P250YHM-A, connected to 8x Indoors. (4x indoors fed from a master BC box and 4x indoors fed from a slave BC box) Could not access BC boxs on my visit for model no.s.

1) Pump down/recover refrigerant. (best way of doing this?) all into cooling and put one on test run or use dip switch on outdoor?

2) Re locate 2x indoors fed from the slave BC box - keep the same addresses?

3) Dis-connect the other 2x indoors fed from the slave BC box and remove indoors and pipework from system as no longer required - blank off flare nuts with 5/8" and 3/8" blank nuts? Addressing?

Many thanks,

marc5180
18-01-2014, 10:45 PM
I'd probably recover the whole charge.
I don't like to pump these systems down.....I've had a few where the service valves are passing and when pressure testing it has leaked through.

Relocating the 2 indoors - yes, it makes sense to keep the same indoor address.

If your taking out 2 of the indoor units then it would be ideal if they were the last 2 addresses on the system, then you could just carry out a Virgin restart (SW2-2 on the outdoor) and let the system auto address. I'm not sure of the exact size of the flare nuts but these can be fitted to the BC box, either with the copper bonnets on them or a piece of braised pipe

install monkey
18-01-2014, 11:19 PM
just make sure the 2 u take down get reconnected to the same port

install monkey
18-01-2014, 11:22 PM
mitsi dont recommend pumping down, as mark says, by degassin the lot then your garenteed that you dont have any other issues afterwards,as valves do pass, dont forget you may need to adjust the charge as youve removed 2 systems and relocated 2

Slim R410a
19-01-2014, 09:03 AM
Thanks guys,

Others have also mentioned not to pump down due to the valves passing so will recover the lot.

So for example if the 2x indoors we are relocating are no 7 & 8 - keep this address the same on the BC ports and indoor units. (and obviously use same pipework connections)

If the 2x indoors that are going are no 5 & 6, keep this address the same on the BC ports? Will the system therefore not 'see' that we have removed them?

install monkey
19-01-2014, 10:06 AM
any local remotes- may req group control editing and also delete indoors off g50 centralised

marc5180
19-01-2014, 10:38 AM
Once you have removed 5 & 6 and carried out virgin restart.
The system will look to carry out an electronic handshake with each connected indoor unit, if you have removed for example 5 & 6 then it won't see that indoor or which port it was connected to (because the bc port is also set from the indoor unit PCB on SW14)

So it would count, indoor 1, 2, 3, 4, 7, and 8.
If you decide you want to readdress them to follow suit, then you would need to change the indoor address, the remote controller address and the central controller address on the 2 addresses. The first 4 won't need touching.
Don't forget to delete the address out of the central controller before you virgin restart. I'd also delete the address from the local remote controller (filter & filter swing to get into engineers mode)of the units that you are taking out completely otherwise you could end up with a ghost address fault (6600)

Slim R410a
20-01-2014, 10:45 AM
Each indoor has its own PAR-F27 local remote. There is also a schedule timer which (I think) is linked to this system and 3 other PUHY systems.

So will anything have to be re-addressed if I am using the same address/ports for the other 2x relocated indoor units?

marc5180
20-01-2014, 01:29 PM
Each indoor has its own PAR-F27 local remote. There is also a schedule timer which (I think) is linked to this system and 3 other PUHY systems.

So will anything have to be re-addressed if I am using the same address/ports for the other 2x relocated indoor units?


If that's the case then just delete the addresses from the local remote controllers on the 2 indoor units that you are taking out and carry out a virgin restart.