Cellar Cooler Icing Problems

[Baz]

Hi All, i'm in need of some advice. I have looked at a 12month ish old Beer Master cellar cooler, supplied by the Climate Center, Condensing unit is model BMO-150-1 and evap is model BMI407-69 charged with R407c which had stopped working. after by-passing low pressure switch and with my gauges attached, the comp was pulling down into vacuum at -0.5 bar g, thinking that the unit was under charged i proceeded to charge the unit only to get heavy frosting on the suction line at the comp, thinking that it may have moisture, i recovered, vacuumed (no leaks found) then i purged the system with OFN (still no leaks present) when i charged again the same thing happened, low side frosted at comp and kept pulling into vacuum. (it was difficult to charge accurately as no weights were on the id plate and sight glass was positioned vertical) I did not change filter dryer as it was brazed in and i did not have a spare and the TEV has also not been replaced. If anybody has any advice it would be much appreciated.

[nike123]

First check evaporator air flow by measuring with anemometer.
What is in sight glass?
It doesn't much mater the fact that sight glass is positioned vertically. It still gives you indication of blockage before him. Check temperature drops at elements on liquid line from condenser to TXV. If everything OK check function of TXV.

[tonyelian]

hi baz
did u check the evaporator fan runs or blocked evaporator

[Kp3]

sounds like tev is faulty, if you charge it to a fall sight glass you will be fine

[thebigcheese]

sounds like tev if ur fans etc are ok.... 407 on a cooler???

[bernard]

I agree as long as the evap fan is running then your TEV is the problem.Make sure the bulb is fitted correctly,set the adjusting screw back to the centre postion and run then set up your superheat.

Regards Bernard

[Baz]

Hi All, Thanks for all your suggestions, the evap and condensing fans are all working ok. I will check air flow but i think its fine, and will look at the TEV. will let you know how it goes.

[Gary]

Before you blame the TXV, check it for plugged inlet screen.

[wilks]

even tho the evap looks clean doesnt mean it is , first thing to check is air flow across the evap , like i said before 95% of calls for evap ice ups are dirty coils .

[wilks]

sorry , 95% of cellar cooling ice ups are down to dirty coils .

[JustinARC]

Yep sounds like to me the evap is blocked with crap! or even iced up. May need pressure washing.