Calling fridgies - Building a coolroom (advice needed)

[Airgead]

OK. So my shed is now built (well almost) and the coolroom is ready to be lined with insulation (100mm high density foam which is r3.3 plus r4 wool in the wall cavities and under the tin roof plus a layer of reflective foil). Its 1.8 long, 1m wide and 2m tall (minus 10cm on all sides for insulation) so its a pretty small space. All I need now is to work out how to cool it...

I have a few options -

1 - I have an old window air conditioner. With an external controller that should get things down low enough but could be prone to icing up and will be noisy. This is the easiest option. Just stick it on and turn it on.

2 - I have an old fridge. Would it be possible to rip it apart, use the compressor and coils to run the coolroom. i'm guessing it would need to be de-gassed, have some extra pipe added so the compressor could be outside the room and the coils inside then get re-gassed.

3 - As above but with an old chest freezer. That might work better as it might be easier to pull apart and is designed to cool lower than a fridge. Its also starting to rust and needs replacing anyway so will sit better with the missus.

Any fridgies out there who could give a considered opinion? Even better are there any fridgies out there (in Sydney) who would be prepared to help put it together in exchange for cash and/or beer?

Cheers
Dave

 

[hoppinmad]

Try this link http://www.mrmalty.com/brewstuff.php

 

[Airgead]

Yeah I've seen that (its where I got the idea from in the first place). Problem I have with the AC is that its an old one and is noisy as anything. Since the shed is hard up against the fence (and near our bedroom window) I'd rather use something quieter if I can... hence me looking at my fridge and chest freezer.

Cheers
Dave

 

[MastersBrewery]

I hate saying search but I'm almost out the door for the night. There is a specific controller (name escapes me) used for AC units in coolroom situations, check DIY on HBT. I know I have read a few buildups there and it may give you some tips on further insulation.

MB

 

[Ducatiboy stu]

2 & 3 will be tricky.

 

[wide eyed and legless]

Just buy a small split A/C, that's what I did cheap to run easy to install and quiet.

 

[seamad]

I'm looking at using one of these http://storeitcold.com/

 

[TheBigD]

I'm a fridgie
1 the unit will ice up at lager temps but will be ok for ales
2 won't have the capacity to cool a room
3 same as above

You really need a fan force evaporator and condenser sized correctly for your cool room

 

[Airgead]

Yeah. I'm looking at that coolbot as well... trouble is the old AC I have isn't suitable (not digital controls)... so I would have to buy something.

2 & 3 will be tricky.

Yeah... I'm hoping a smart fridgie will be prepared to work for beer... I wouldn't consider doing it myself.

Just buy a small split A/C, that's what I did cheap to run easy to install and quiet.

I'm giving it serious thought... trouble is its something I have to buy. Given I have slightly overspent on the shed already, the missus won't be too happy.

I'm looking at using one of these http://storeitcold.com/

Yeah.. looking at that. But the old AC I have isn't suitable so would have to buy something... see above.

 

[Airgead]

I'm a fridgie
1 the unit will ice up at lager temps but will be ok for ales
2 won't have the capacity to cool a room
3 same as above

You really need a fan force evaporator and condenser sized correctly for your cool room

I'm a fridgie
1 the unit will ice up at lager temps but will be ok for ales
2 won't have the capacity to cool a room
3 same as above

You really need a fan force evaporator and condenser sized correctly for your cool room

I'm not sure about 2 and 3.... its a pretty small space and will be opened very infrequently (maybe once a week at most). I have seen fridges that are bigger than the room so it might be possible.... Think of it as a fridge with the door removed and a long insulated tunnel fitted to the front... then the door put back on.

Maybe possible?

I know a proper coolroom unit would be better but $$$

Cheers
dave

 

[TheBigD]

The a/c units your best bet you could bypass the thermostat and just plug it into one of those electronic ebay temp controllers and wire a de-ice controller into the a/c if it's reverse cycle. I'd imagine you could get the temp down to around 8 degrees no trouble. I don't know how long the a/c would last though.

 

[shaunous]

Surely a window rattler A/C wouldnt last very long cooling down to cool room temps???

I ask because I have one sitting around doing nuttin, and I really really want a cool room, but I cant justify spending big dollars on a proper compressor yet.

 

[TheBigD]

Most recent roomies use a rotary compressor with a suction accumulator which can handle a certain amount of liquid flood back so you might be supprized. What kills them is high amps and liquid flooding into the compressor which obviously can't be compressed however yo may be able to strike a balance with a particular temperature and a de-ice controller. Lower temp means lower head pressure and lower current draw it's the liquid flood back you'll need to worry about.

 

[mash head]

If its any use I have a split cycle a/c in my cool room. the thermostat has been bypassed and it runs with a digital controller. I had problems with it icing overnight for cold temps so I put a floor fan hard up against the evaporator and ran it all the time, seems to work. Had it at 4 degrees for a couple of days while I hung some sheep. This is the only time Ive asked it to get that cold so how it copes with continued use at fridge temps will be seen.

 

[mash head]

I have a mate with a mobile coolroom and his evaporator is just lengths of copper pipe screwed to the walls, the compressor is an old a/c twin piston pump off of a car. It takes a while to get cold but once its there is pretty efficient.

 

[Ducatiboy stu]

Icing is the biggest prob with an A/C. If its an older one its not hard to wire in a thermostat to stop it icing up. This works in tandem with your normal room thermo. Basically the icing thermo sits across the cooling fins and when icing form ( ie you set itfor 1*c) it turns the compressor off. The important thing is to rewire the fan so it constantly draws air thru the fins when to compressor cuts out. This helps it to de-ice quickly.

 

[mrsupraboy]

I'm a fridgie
1 the unit will ice up at lager temps but will be ok for ales
2 won't have the capacity to cool a room
3 same as above

You really need a fan force evaporator and condenser sized correctly for your cool room

Completely agree. Fridgie to Fridgie.

These days u can get Ur self a nice little set up from fridge suppliers that will easily handle Ur load and cost Ur about 500. It would use less electricity and the gas in the unit would be designed to work at lower temps. Most old a/c units run on r22. Will most likely ice up on any temp below 20.

 

[MastersBrewery]

I'm looking at using one of these http://storeitcold.com/

these guys disagree with you both

Completely agree. Fridgie to Fridgie.

These days u can get Ur self a nice little set up from fridge suppliers that will easily handle Ur load and cost Ur about 500. It would use less electricity and the gas in the unit would be designed to work at lower temps. Most old a/c units run on r22. Will most likely ice up on any temp below 20.

Ice is dependent on available moisture, something AC's are renowned for removing though the coolbot controller was made for this specific purpose of preventing freeze ups. As far as cooling capacity, it's documented variously including the storeitcold web site linked above.

 

[Ducatiboy stu]

Yeah. I'm looking at that coolbot as well... trouble is the old AC I have isn't suitable (not digital controls)... so I would have to buy above.

The coolbot is nothing more than a fancy thermostat. Its sensor sits on the cooling fins. So when the fins start to ice it turns the unit off. It doesnt allow the fan to keep working and allowing the unit de-ice quicker.

There is heaps of fluff in the coolbots spiel. Its just an external thermostat with some fluffy marketing.

http://youtu.be/9vQaVIoEjOM

 

[stew.w]

U can buy packaged cool room units. I'm a fridge too and have put some in. Unless you seal the room u are going to have endless problems with iced up coils if you are talking about running this at fridge temps. I think if u bypass an ac unit thermostat to run those temps the compressors just going to shit itself anyway