How To Size A Brewery Water Chiller?

Wondering how to size a Brewery Water Chiller? Here is a step by step guide. Read every word or just follow the examples. If you need help, our sales engineers will be happy to assist you.

1. Calculate the total volume in gallons for fermenters pulling down simultaneously

2. Multiply the total gallons by 8.33 to get total pounds

3. Multiply the total pounds by your temperature difference

4. Divide by the hours of your pull down (crash).

This is the Btu/hr required for your pull down process. Many brewers will add 10% or 15% to this number to compensate for extra heat being added by the pumps, heat loss and inefficiencies of their systems.

2. Multiply by 280 Btu / brick

3. Divide by 70 hours

III. Add the pull down load and the active fermentation load together for your total fermentation Btu/hr load

IV. Cold Liquor Tank (CLT)

2. Multiply the total gallons by 8.33 to get total pounds

3. Multiply the total pounds by your temperature difference of your water source minus target CLT temp.

4. Divide by the hours of your recovery time (time between batches)

This is the Btu/hr required for your CLT. Many brewers will add 10% or 15% to this number to compensate for extra heat being added by the pumps, heat loss and inefficiencies of their systems.

2. Multiply the total gallons by 8.33 to get total pounds

3. Multiply the total pounds by your temperature drop

4. Divide by the hours of your recovery time (time between batches)

This is the Btu/hr required for your wort. In most breweries, 100% of the water chiller load will be diverted for 2nd stage wort cooling, until the desired temperature is achieved, the diverted back to the tank cooling. Wort cooling is typically achieved in one hour or less with minimal impact on tank cooling.

1. Make sure that the chiller your are purchasing is sized properly. In our example, Amrta chiller needs to be able to provide 19,518 Btu/hr @ 28F Leaving Glycol Temp. Chillers in the US are sized by either tonnage or horsepower. In either case, you want to make sure that the chiller also factors in your glycol percentage. Typical glycol percentages are 30% to 40% glycol to water depending on your lowest outdoor air temperature where you live or 28F degrees (whichever is lowest). Propylene glycol will require more surface area in the heat exchanger than will water.

NOT ALL CHILLERS ARE CREATED EQUAL

Chiller capacities are based upon many factors. The major factors are fluid temperatures, ambient air conditions, fluid being cooled and compressor performance data. A refrigeration ton = 12,000 Btu/hr. Many chillers are rated for Air Conditioning standards, which are 44F leaving fluid temp. / 54F entering temp. and 2.4 gallons per minute per ton. A Brine Water Chiller will need more horsepower than an air conditioning chiller. In fact, an air-conditioning chiller may not operate properly or may not operate for very long due for a brewery due to the lower temperature required for a brewery. Operating at lower temperatures than what the chiller is designed for can also cause the compressor to fail prematurely. Amrta Chillers engineers its brewery chillers to perform at brewery conditions. When ordering, we ask for your conditions to make sure the chillers are sized and engineered accordingly.

In our sizing example above, at a quick glance, it would appear that a 2 ton chiller would be sufficient (2 x 12,000 Btu/hr = 24,000 Btu/hr). BUT, we need to know the design standards of the chiller. The cooler the fluid, the more compressor horsepower and the larger the evaporator (heat exchanger) required. The evaporator will also need to be larger when cooling glycol VS cooling water. In air-conditioning, where 44F is the desired fluid temperature, glycol may not be needed (especially if the air-conditioning chiller is being installed in a warm climate).

Make sure that you are calculating your worse case scenario based on the amount of brewing that will take place simultaneously. This is the time to consider any plans for future growth. If that growth is in the near future, it may be beneficial to oversize the chiller now so that you aren`t forced to purchase additional equipment later. Of course, if your planned growth is substantial or you are over sizing the chiller by a great amount, you could have adverse results if some sort of capacity control isn't built into the chiller. If your growth is more than 2 years out, you may be better off to purchase a smaller chiller now and add additional modules later.

As you can see, there are many factors to consider when purchasing a chiller, but with the proper engineering of your system, your brewery chiller should last for many years. If you need help sizing your brewery chiller, please contact a sales representative at info@amrta.com.cn. We are happy to assist you.