toshiba unit

[bangoman]

commissioning a new toshiba install with two indoor units rav -sm562krt-e and outdoor rav -sm1102at-e.Bth units nt cooling bt compressor running .back pressure is standing pressure like compressor nt running at all.Checked pumping efficiency ok. units running on R410A

[nike123]

commissioning a new toshiba install with two indoor units rav -sm562krt-e and outdoor rav -sm1102at-e.Bth units nt cooling bt compressor running .back pressure is standing pressure like compressor nt running at all.Checked pumping efficiency ok. units running on R410A

Check 4 way valve!

[paul_h]

commissioning a new toshiba install with two indoor units rav -sm562krt-e and outdoor rav -sm1102at-e.Bth units nt cooling bt compressor running .back pressure is standing pressure like compressor nt running at all.Checked pumping efficiency ok. units running on R410A

What happened when you tested pumping efficiency, ie what did you do, what were the readings?

[Brian_UK]

Check valves are open.

[bangoman]

??????? check valves or check the valves .No check valves on the unit just the 4 way reverse cycle valve

[Loops]

Hi Bangoman,

I think Brian is saying check that the service valves are open.

What compressor pumping test did you do? A pump down test? Or what?

There are a couple of other things to check;

1. Gas charge. Note these outdoor units are pre-charged for 30m as a single split but 20m if a twin split (18m main pipe and 2m branch) - so check your additional gas charge calculation.

2. Wiring; this is frequently wrong. Outdoor to master indoor connections 12&3. Master indoor to slave indoor connections 1&2 only AND connections A&B. Optional connection A&B from Master indoor to wired controller. (You can use the supplied infrared controler but only communicates with master indoor).

The common error is the '3' wire between master and slave - do not connect. If it has been you'll need to correct the connection and then re-configure the address set up (wired controller for this).

I'd also suggest checking your pipe work isn't blocked - liquid line filled with brazed for example or a kinked pipe.

Cheers

Loops

[Loops]

Sorry should have asked what happens if you try heating mode?

The reversing valve is energised for heating. If the valve hasn't settled fully one way or the other then energising to give heat may help.

Cheers

Loops

[paul_h]

??????? check valves or check the valves .No check valves on the unit just the 4 way reverse cycle valve

If it's capillary or mech TX valve system, there will be check valves so the refrigerant goes "the right way". From the infomation you've given, check valves seem the most likely cause.
Electronic TX valve systems often don't have check valves though.
There's no way to test compressor pumping unless you can isolate the reversing valve anyway, as a faulty/stuck reversing valve will stop a compressor pumping down, hence my previous question, how did you verify the compressor pumping efficiency is good?

[bangoman]

thanks mates isolated the 4 way reverse cycle valve to find that its the culprit.stuck on heating mode .