Ambient temperatures

[Philip d1]

I had a Toshiba split on test run which I was getting 19 bar max head pressure and 5 bar back pressure I was thinking low on charge but now I’m thinking as ambient outdoor temp was 2 degrees Celsius was this causing the low head pressure it was R410a should i not be getting at least 25 bar high side

[cadwaladr]

Sounds a little low on delivery is there no fan speed control fitted?

[Philip d1]

It’s a new enough unit so I was thinking it should have fan speed controll I’m also just getting 32 Celsius in heat mode and 14 degree Celsius in cooling off the indoor but I was then just thinking of the ambient temp outside could this be catching me out on the pressure

[Brian_UK]

Is it running with an inverter compressor, if so then your pressures don't mean anything apart from that it is running.

[Philip d1]

Yes it is an inverter compressor so that’s why I had put it in test run to judge my pressures can u still not judge them in test run I thought in test run the compressor is at full speed more or less

[charlie patt]

Pressure is not a issue as invertor your air off air on is not correct however it relates to setpoint and position of pmv do you have a remote hardwired or info red
air of coil normally single figures heat 40 ish depending on ambient you really need to see Hz speed reading of comp and position of pmv this will advise if short
Both your pressures are short should be low approx 7 bar head is variable
May I ask has evap ever frozen solid or is it mainly on heat
even at ambient plus 2 you should have a low side pressure of 7 ish bar

[Philip d1]

It’s an hard wire controller it’s always on heating I’ve being told.it was a split so there was only one access port on suction so I only got the high side pressure on heating and cooling low side pressure which was 7 bar I’m back tomorrow to reclaim and weight compare to commissioning report.with the Pmv I need the hardware to read this which I only have for mitsubishi electric

[Brian_UK]

You might find the second access port inside the unit casing.

[charlie patt]

Second port is inside casing do you have a nice LCD controller or bit of a basic one both will give u info but the LCD one gives more you can sea what load its under and crossreference it the highest head you will get on these as this ambient is approx 400 psi that gives u approx 45 dc of condensor
When diagnosing faulty valve run flat out for 1,2 a hr and monitor temp then set temp to room temp you should hear condenser ramp down if it does ramp down but suction runs on a low pressure and liquid line start frosting heavy pmv ain't shutting down on heat if left it will freeze condenser if on cool will freeze evap solid