Professional Member
The bar called and said that their beer lines were frozen up. I got there and found them not frozen up. Apparently "the beer guy" ran hot water through the system to thaw them because they froze overnight. Nobody at the bar can tell me if the beer in the hoses from the kegs in the walk in cooler was frozen or if it was just frozen in the beer taps. I have no idea who this "beer guy" is. Boss says that we have been there in the past for frozen lines and the problem was the walk in box was too cold. Of course he told me that after I was there.
So I'm scratching my head about a few things. It's a Glycold unit with an air cooled condenser coil sitting in the walk in cooler. How does an air-cooled condenser work with a 35 degree ambient temperature? It was running 60 psi liquid pressure (134a). As far as I could tell both the Glycold unit and the walk in cooler were operating normally when I was there.
I'm on call this weekend so I have a feeling I'll be going there tomorrow when it's frozen up again.
Professional Member
The "beer guy" might be the company that services the taps and lines.
Many years ago when I was working in a resturant we had a company that came in and cleaned / sanatized / repaired the draft lines and beer taps. I can't remember if it was scheduled weekly or monthly service.
Professional Member *
I have had similar problems with managers cranking temps. down. Beer sells better the colder you can get it.Originally Posted by fv_tom
I would recommend installing tstat in the fan coil. Leave old one where it is. While hiding new one where it cannot be seen or gotten to very easily. You leave old one where it is so they have something to play with. You can wire it in series so that they can raise temp but not lower it. If it freezes up after that then the problem is elsewhere.
Banned
it's better to just;
wire in a ranco digital temp control and flip the little toggle switch inside (to lock mode)
no more worries about idiots changing the setting
.
Professional Member
I agree.
Professional Member
The Glycol unit is in the walk in? Needs to be on top of the walk in and it is not designed to run in such of a low ambient condition. I have seen icemakers installed in gas stations in walk in coolers and they wonder why they have harvest issues????
Professional Member *
Will still get calls about being to hot and that the tstat does not work because they cannot change temp.
Besides I have found that electronic tstat do not hold up well down here because of power surges. I have had to replace three at one location and finally switched back to mechanical.
Professional Member *
OOOPS! I had to reread. I missed that. You are right it will never work right.
Banned
if it's hot, repairs need to be made
we can't teach your customers, that's your job
it's your job to teach your customers, not to phuck with the equipment
i don't have any customers that need different temps for different days of the week in the same box
why does your customer need to change temps?
.
Professional Member
the unit is not designed to run in that ambient temperature, you should move the unit to somewhere in the 60-90f ambient range, 70-75 is ideal.
Seems like the compressor is still running ok, pt chart says 62f at 65 psig. So your still 35ish above ambient. Most glycol systems i have seen run a capillary tube, so with your head pressure so low, your suction pressure will also be low, you probably have uneven temperatures on the evaporator coil. Depending on where your thermostat bulb is, in the bath or on the coil, it will either run constantly and freeze on a regular basis, or it will short cycle. thermostats for glycol systems should be set at 26-28f. If its a dial style thermostat 1-9 or whatever you need to put a temperature probe in and set it to cut out properly.
So the root cause is the low ambient conditions.
THE Best option is to put the glycol unit in a proper ambient.
If the owner does not want to move it you might be able to get away with a pressure fan cycling control on the high side, maybe a cut in at 150 cut out at 110psi. Wire in series with the condenser fan. This will keep the head pressure in a proper range and your suction pressure will rise and maintain a better temperature in the glycol bath.
The suction pressure should be 15-19 psi.
Professional Member
The boss says "they always put those units in the walk in".
I still can't believe I never got called back. Apparently it works like a charm.
Professional Member *
For one thing. It is not my job to teach customers anything. If they want to learn then they need to pay and go to school.
For another, what you refer to as phuck with the equipment. Is what the corporate office for the store authorized me to do to stop a hard headed store manager from freezing up the unit.
The store manager kept turning down the tstat to 30 degrees so that his beer would sell faster. He was instructed several times that was what was freezing up the unit (also was noted everytime on the invoice). He actually told me I did not know what I was talking about.
So.
Regular Guest
you know I am curious just how long the line runs are for this draft system, really glycol cooled lines are just meant to maintain the temp of the beer not cool it further.
If he has the glycol unit in the walk in why does he even need a compressor how about just heat exchanger and pump and a tank for the glycol. if he wants is 30 degrees in there. most domestic light beers are only 4 to 5% alcohol of course it will freeze at 30
Professional Member
The beer lines are 50 or 60 feet long.
Regular Guest
sounds like the guy doesn't understand that alcohol can freeze too
Professional Member
Perhaps you are talking about the old round barrel Kold Draft Beer Glycol/water Chillers that have to be mounted in the walk-in box?
Professional Member
It looks like your typical condenser/fan and compressor for a small refrigeration unit (like a reach in cooler). The glycol tank is about 1 cubic foot and the evaporator is in the tank wall. There is a pump for the glycol just beside the condenser fan. One of the journeymen at my company theorizes that it works because the walk in box is actually what is keeping the glycol cold, and the compressor for the glycol unit barely runs.
Regular Guest
I doubt that the compressor is needed just a heat exchanger and a small pump to move the glycol
Professional Member
I'd call Perlick and ask them for the standards. Run length, quantity of lines, thickness of insulation, temp set points of walk in where the kegs are stored, and what the glycol temp should be. I used to work on these a long time ago. And I found Perlick to be the industries leading supplier and knowledge resource.
I think there is a Temp difference that you base your setpoint on. TD. If your storing at 34 in the box, and you want 34 at tap, the glycol running in the bundle would be 5 or 10 degrees less. Just like TD in refrigeration. Example. 35 degree box, 15 degree td, Saturated Suction temp would be plus 20. And I remember having to sort of try different setpoints to get it just right.
Posting Permissions
Reply