Cold chamber.

[martin99]

I have been trying to get a cold chamber to run as well as i can. the chamber chills new engines to minus 30 , here are some readings i have taken. Any ideas on what i can do to improve on these.
H.P. pipe temp-34c
discharcge temp 75c
H.P. 220 psi
L.P. 9 psi
suction pipe temp varys, minus 18 to minus 24
chamber was at minus 17 at time readings were taken.
Unit runs on R404a and has adjustable expantion valve. Both coils are clean.

[Brian_UK]

Has the chamber ever reached your required -30°C?

[martin99]

yes it has.

[Emmett]

are you reaching -30 now and are just looking to "improve performance"? or are you experiencing a problem with the unit not pulling down to temp?

[martin99]

it does reach minus 30 and it does not have a problem. I was wondering what people thought of the figures and could they be impoved.

[Emmett]

Difficult to tell with the limited information, do you have the design spec's? that is where you need to start, superheat, subcooling, refrigerant charge, etc.