emerson refridgeration unit

[megawatts]

I have an emerson unit it was running and icing up around tev i check gas and found it was short of gas pressure tested and no leak found top up with r407c and unit running ok. After a week checked unit and it had iced up on evaporator coil. Checked tev and filter dryer and both seem ok. Had anyone got any ideas on why this happens and how to resolve it

[monkey spanners]

Chiller or Freezer? What sort of defrost system does the system have? Are the door seals and panels in good condition? Is the drain clear?

[cool hand fluke]

Guessing its a cold room if it's 407c.
Is the whole of the evap iced or just the start by tev.
If just the start, sounds short of gas again. Go around with your
Sniffer while it's still got a charge to give you a rough area.

If it's all iced yeah drains, defrosts, doors being left open fans ect.

Bryan

[gsracer]

R407c is a blend, so if it had a leak it's probably not the correct blend any more

[megawatts]

Thanks guys. Its a unit in a data centre there is no defrost setting that I have found as its all controlled by a trend system, its iced around 1/4 of coil to tev. I have increased fan speed to help but as there are 2 circuits on system its the 1st one that has faults

[manhnghia]

The PAC not enough refrigerant R407C, may be has leaking on system.