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kiwibrewer
04-21-2014, 02:34 AM
Hi Guys,

Our brewery is looking to upgrade our main cooling system as it has trouble preforming in the ambient heat of summer, for the 8FV's, 6BBT's and HX that it cools (our brewery can top 40*C/105*F during June/July). The poorly designed setup has the fans for the compressor located right inside the brewery next to the HLT! Good luck cooling down in the summer. Therefore my first move will be to get these guys put outside, following that I need to make a move on the cooling tank and compressor itself.

Few quick questions, as I've been given some inconsistent feedback from the three main suppliers I've contacted.

Company A says: We need to increase the size of the compressor from 5HP to 8HP, this will also require an increase in size from a 1500L Glycol tank (they did not specify the next step up in volume)

Company B says: Increase the size of the compressor from 5 to 8HP, but leave the tank as is. It will be OK.

Company C says: Just move the fans outside and it'll be fine (love this guy, he's so casual!)

Company D says: We can add some extra part to the compressor (it got lost in translation exactly what this part is or what the function will be, but my Chinese assistant said it will increase the cooling power somehow)

Whew.

Any thoughts much appreciated guys! Sorry if I forgot any crucial info on my system here, just let me know. I'm under the clock to get this sorted before we have another massive summer of cooling drams like last year!

Thanks,
Fraser Kennedy - Head brewer, Dr. Beer, Shanghai.

Starcat
04-21-2014, 08:22 AM
Hi Guys,

Our brewery is looking to upgrade our main cooling system as it has trouble preforming in the ambient heat of summer, for the 8FV's, 6BBT's and HX that it cools (our brewery can top 40*C/105*F during June/July). The poorly designed setup has the fans for the compressor located right inside the brewery next to the HLT! Good luck cooling down in the summer. Therefore my first move will be to get these guys put outside, following that I need to make a move on the cooling tank and compressor itself.

Few quick questions, as I've been given some inconsistent feedback from the three main suppliers I've contacted.

Company A says: We need to increase the size of the compressor from 5HP to 8HP, this will also require an increase in size from a 1500L Glycol tank (they did not specify the next step up in volume)

Company B says: Increase the size of the compressor from 5 to 8HP, but leave the tank as is. It will be OK.

Company C says: Just move the fans outside and it'll be fine (love this guy, he's so casual!)

Company D says: We can add some extra part to the compressor (it got lost in translation exactly what this part is or what the function will be, but my Chinese assistant said it will increase the cooling power somehow)

Whew.

Any thoughts much appreciated guys! Sorry if I forgot any crucial info on my system here, just let me know. I'm under the clock to get this sorted before we have another massive summer of cooling drams like last year!

Thanks,
Fraser Kennedy - Head brewer, Dr. Beer, Shanghai.

Increasing the size of the compressor means increasing the size of the " Condensing Unit." This means not just the compressor, but the condenser, evaporator and all that links everything together has to be matched. One cannot just change the " compressor " and leave everything else as is. The glycol well size is far less of an issue in this matter.
Without more information it sounds like you are short on capacity. While any refrigeration system may be " optimized " by a savvy Tech, its not really possible to get it to deliver more than it was designed for in terms of BTU/hr.
Sounds like you are saying that the existing unit is set up with a remote condenser that is close coupled and discharging air indoors.
While this is not good refrigeration practice, what has to be understood is that moving said condenser outdoors is not necessarily going to solve anything in a major way.
It depends on what the Condenser Entering air temperature is relative to what it was before the move. If that number is decreased, then there can be some efficiency gained, but its not going to be major.
The correct way is to have the load calculated by a Chiller outfit that sells chillers for Breweries. This is all based on math from your system and its duty.
Then you have everything " sized " to handle the demand without being overloaded. If you are flying seat of the pants and you know you are undersized, then sometimes adding a few more horsepower can work out.
One thing a lot of small Breweries fail to see is that redundancy of chiller equipment is absolutely necessary.
That means you really need more than one machine that can be valved on the main glycol supply and return header because your operation cannot run without cooling.
That make it super cirtical.
Otherwise your machine had better be golden reliable and you better have an HVACR guy close at hand for when its not.

All the best

jimvgjr
04-21-2014, 09:25 AM
Hi Fraser,

I received your email and am sorry but am stuck in meetings all day and not able to respond in as much detail as I'd like- at this time.

I'd like to run the cooling loads, this will then at least tell us the capacity your system requires. If you could complete our online survey here, we will run the loads and use this as a starting point. http://www.prochiller.com/brewload.html
Please list in the note section that you are just looking to confirm the total cooling load at this time and working with Jim on this.

I can definitely agree with all of Warren's points. If you have adequate cooling system capacity- relocating the condenser may make the best sense but we need to make sure the new condenser location provides adequate air flow at the right entering temperature.

Thanks,

Jim VanderGiessen JR
Pro Refrigeration Inc.
jimvgjr@prorefrigeration.com

kiwibrewer
04-22-2014, 02:02 AM
Hey.

Thanks a lot guys!

Jim, I've sent a load request through your website. Really appreciate you taking the time to answer even though you are busy.

I'll fire this feedback through to the Chinese engineer I'm working with and hopefully I can find a good solution for the issues I'm facing here.

Question re: the location of the condensing unit. Outside temps can hit 90-95 here in Shanghai in the heat of the summer, will this still be OK for our condenser? or is there a specific way to make sure that it can handle these temps?

Can you have too big a condenser?

Cheers,
Fraser

kiwibrewer
04-23-2014, 08:52 PM
One more quick question guys,

I have been told that we could look at installing a small HEX unit to run the refrigerant against the glycol, it this plausible as a means of increasing my cooling speed for the reservoir?

Currently my tank is cooled via a 3sqM cooling plate - is this efficient enough in your opinion?

Cheers,
Fraser

Starcat
04-28-2014, 07:57 AM
One more quick question guys,

I have been told that we could look at installing a small HEX unit to run the refrigerant against the glycol, it this plausible as a means of increasing my cooling speed for the reservoir?

Currently my tank is cooled via a 3sqM cooling plate - is this efficient enough in your opinion?

Cheers,
Fraser

If your current chiller system uses a plate evaporator immersed in a glycol well to transfer heat, you have an antiquated system that is not up with modern brewery HX standards as applied on Glycol chillers. If the machine is already overloaded or in difficulty on the condenser side, this kind of retrofit will compound the problem.
Sounds like you really need a better machine rather than trying to re-engineer an outdated one.

kiwibrewer
04-28-2014, 11:52 PM
Yup, antiquated is an apt description of the brewery in general!

So I'm looking to settle on a complete overhaul of the existing design here.

Upgrade from 6HP to 8Hp on the compressor, move the condensing unit outdoors and upgrade this to match the system (also providing a solid location to maintain that good airflow).

HE interface for cooling the the Glycol well.

New insulation on all my glycol lines.

Bring in a new technician who actually knows his stuff to make sure it all comes together smoothly!

This sounding OK?

Cheers,
Fraser