cellar cooler icing up

[tayler46]

Hi all


recently installed a new cellar cooling unit. ran for a week then had a call saying it was high in temp. upon arrival both evaps where eavily iced up with soft ice on the coil and hard ice on the coil end. defrosted coil and tested system ran up cooling ok. if the cond fan is running can't get head pressure above 170psi (r404a) and 50psi suction pressure. runs for a few days with 6 degrees across the coil then ices up again. got it running on a pressure control for the cond fan to get the head pressure and suction up.. any help would be great thanks in advance

[wilks]

Hi all


recently installed a new cellar cooling unit. ran for a week then had a call saying it was high in temp. upon arrival both evaps where eavily iced up with soft ice on the coil and hard ice on the coil end. defrosted coil and tested system ran up cooling ok. if the cond fan is running can't get head pressure above 170psi (r404a) and 50psi suction pressure. runs for a few days with 6 degrees across the coil then ices up again. got it running on a pressure control for the cond fan to get the head pressure and suction up.. any help would be great thanks in advance

is the condenser outside ? whats the ambient temp ? if its outside and the temps low thats whats giving low pressures. Is the model fitted ok to work in these ambients ? u might need a fan speed control. I take it the evaps clear and fans are working .? does it still ice up with the pressure switch fitted ?

[chillled]

Just set the LP switch to run a 'wet cycle' as we used to, keep the evap temp above freezing, or you could fit a cheeky timeclock to turn the cond unit off every night say from 4am to 9am while the landlords in bed!!!

[taz24]

Hi all


recently installed a new cellar cooling unit. ran for a week then had a call saying it was high in temp. upon arrival both evaps where eavily iced up with soft ice on the coil and hard ice on the coil end. defrosted coil and tested system ran up cooling ok. if the cond fan is running can't get head pressure above 170psi (r404a) and 50psi suction pressure. runs for a few days with 6 degrees across the coil then ices up again. got it running on a pressure control for the cond fan to get the head pressure and suction up.. any help would be great thanks in advance

Stop worrying about the discharge pressure and start thinking about what the suction is doing.

Cheers taz..
..

[brunstar]

yeah i would just do a time initiated defrost, it sounds like the bottom of it is not defrosting and it is working it's way up the coil.

[chillerman2006]

Hi all


recently installed a new cellar cooling unit. ran for a week then had a call saying it was high in temp. upon arrival both evaps where eavily iced up with soft ice on the coil and hard ice on the coil end. defrosted coil and tested system ran up cooling ok. if the cond fan is running can't get head pressure above 170psi (r404a) and 50psi suction pressure. runs for a few days with 6 degrees across the coil then ices up again. got it running on a pressure control for the cond fan to get the head pressure and suction up.. any help would be great thanks in advance

Hi Tayler

sounds like you have either a lack off air flow or are flooding the evaporator, probaly the latter.

Set your superheat to about 6/7 degrees and this will raise your suction pressure.

This in turn will raise discharge pressure then if your still having problems we can look at how your condenser fan is controlled and how to check you are fully charged with refrigerant.

If you need any more info on how to set up private message me an email address and i can forward you stacks of info on commisioning

Goodluck Chillerman

[Slatts]

tayrer, do you have a defrost time clock on the system?
Do you have an LP control on the system?
What temp are you after in the room?
Did raising the HP make a difference?

If it's a beer room, I'd set it up for a 1 hour defrost at the end of trade and 3 or 4 30 min defrosts during the day timed for low usage times. A time clock with battery backup is what I'd recommend. without it your big defrost could end up occurring in high usage times.
In Australia we'd be after a room temp during trade of 0C. I set dirrect pull keg room thermostats to cycle between -2 and +2C. Gives a nice long off cycle.
Hopes there's something in this you can use.
Slatts

[fridge doctor]

Beer cellar temperature in UK should be 11 degrees. If the equipment is up to the job, and has a thermostat control there ought to be no problem.

[Slatts]

Beer cellar temperature in UK should be 11 degrees. If the equipment is up to the job, and has a thermostat control there ought to be no problem.

Damn Doc!
warm beer!
oh well, each to their own.

[fridge doctor]

It isn't the cellar's job to hold the beer at serving temperature, just to pre-cool it before it passes through the so-called 'python' and gets supercooled on it's way to the pump. Or at least that's how it was 5 years ago when I left there.

[paulwild]

thats right, the cellar cooler should be at around 10 c and the final serving temp is acheived by the brewarys kit normally a python cooler or cellermatic system?

[doormaster2008]

what system are you using.is it a beermaster

[wilks]

thats right, the cellar cooler should be at around 10 c and the final serving temp is acheived by the brewarys kit normally a python cooler or cellermatic system?

its all gone high tech now . Glycol cooler plates are used for most largers , super chilled and stuff . Glycol is kept at about - 10oC , some largers are served at or around 0oc .This is the general set up for the JD Weatherspoon estate and big pub chains like that , the local on the corner just standard remote beer cooler with python and water , as it was said before most breweries want pub cellars at 12 oC so no need to bother with defrosts on the cellar cooler , most ice problems on evaps are from dirty coils , infact id say about 95% .This is from venting fob bottles in the cellar and the yeast getting sucked up by the fans causing blockages in the coil . We normally turn system off and hose down , if this fails we use hydra coil cleaner ( as a last resort ver expensive !)

[laf100]

I don''t do a lot of cellar cooling these days, but the most recent I saw on R404a had a pressure switch to cycle the Cond' fan that maintains around 220-260 head. It was an old peice of cr*p but never had a history of freezing up the evap, despite the evap' coil being filthy.

[coolhibby1875]

it sounds like the unit might be oversized as the suction seems very low or maybee the orrrifice is to large i would fit a epr and use this to get a better control on your suction presure sort your suction presure out and the head presure will look after its self as long as its sized correctly.

[nike123]

I think that OP lost interest for that matter, or he solved his problem and don't care to much to respond on all yours solutions. You probably frightened him with all that attention.

[Slatts]

You're probably right Nike, but it keeps us away from the pub

[nike123]

You're probably right Nike, but it keeps us away from the pub

I don't see anything wrong in pub talks!

[Andy W]

I had a beermaster icing up one evap recently, the problem was a tiny particle of copper swarf stuck to the diaphram of the solenoid valve on the biggest evaporator so it was passing liquid all the time.

[mcunliffe4]

dont think u need a de - frost on a cellar cooler, sounds like your sysyem could be undercharged or a possible restriction in your liquid line. did you purge your lines when u brazed your pipe - work.