is it possible

[sean1]

on a beer cellar cooling unit- hubbard running on r134a what could cause high suction pressure- 3 bar and high discharge pressure 23 bar with a large superheat.is it possible

[Gary]

Dirty condenser, fan not working, high ambient temp, etc.

[sean1]

even if the system has a tev fitted? thought high suction was only with capillary as expansion device ?

[Gary]

High suction pressure can happen on either, but is more likely on a TEV system.

[lowcool]

non condensables,unit undersized also

[Magoo]

All the above, listen to Gary's comments.
Have you checked compressor motor current?.
Something will blow soon, nothing surer. R 134A is reasonably tolerant, but compressor, probably not.
magoo
magoo

[Kp3]

with the hot spell were having at the mo in the uk you can expect that on 134a. the units will struggle on 134a on cellar cooler not the best refrigerant to have a cellar on i perfere 407c or 404a get alot better duty at of it. unfortantly it will take a while for it to pull the cellar down pos 24hrs after repair. as gary says make sure cond clean

[andywill]

I have to agree with lowcool, if your liquid line is cool to cold and it is not unit expansion then you must have air/nitrogen in the system, unless it is severley overcharged, especially if the unit has worked before.
If it is the case, decant,pressure test,good vac and if it has a charge weight then weigh the gas back in.

[sean1]

thanks went back today used coil cleaner on condenser and blasted with ofn suction went down to 2.2 bar and dicharge to 15 bar liquid line was too hot to touch before at tev but was warm to touch after room temp was 17 celcius and air off evap coil was 14 celcius