Labs, Plastics, Lasers, Semiconductor, Medical, Pharmaceutical, Extraction, Chemical, the list could go on and on. What all of these industries have in common is they all require a chiller at some point in the process. Determining the size of the chiller required is as simple as following a formula. As long as you have a few facts, it may be done without being an expert. However, if you’re unsure, please do not be afraid to contact us, we’d love to assist you.
How to Size a Chiller
There is a single and easy to follow formula for determining the size of chiller you require. However, there are a few factors you must know before you begin:
- The incoming water temperature
- The water temperature you require
- The flow rate
General sizing formula:
- Calculate Temperature Differential (ΔT°F) ΔT°F = Incoming Water Temperature (°F) – Required Chill Water Temperature
- Calculate BTU/hr. BTU/hr. = Gallons per hr x 8.33 x ΔT°F
- Calculate tons of cooling capacity Tons = BTU/hr. ÷ 12,000
- Oversize the chiller by 20% Ideal Size in Tons = Tons x 1.2
- You have the ideal size for your needs
For example, what size chiller is required to cool 10 GPM from 72°F to 58°F?
- ΔT°F = 72°F – 58°F = 14°F
- BTU/hr. = 10 gpm x 60 x 8.33 x 14°F = 69,972 BTU/hr.
- Ton Capacity = 69,972 BTU/hr. ÷ 12,000 = 5.831 Tons
- Oversize the chiller = 5.831 x 1.2 = 6.9972
- A 6.9972 or 7-Ton chiller is required