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Chillers and Recirculators


Chillers (chiller pricing, subject to change)

MicroMax (download MicroMax manual here)
Downloadable PDF Document MM1000, 1-ton chiller
Downloadable PDF Document MM1500, 1.5-ton chiller
Downloadable PDF Document 2000MC-W, 2-ton chiller
Downloadable PDF Document 3000MC-W, 3-ton chiller
Downloadable PDF Document 5000MC-W, 5-ton chiller
* larger sizes available

Chillers vs. Water Recirculators

What’s the difference between a chiller and a water recirculator?

The major difference between the two is whether or not the unit contains a refrigerant. 

An actual CHILLER will have a compressor and a pump to actively remove heat from the liquid flowing through it, using a refrigerant (much the same way a refrigerator or a drinking fountain works). 

A WATER RECIRCULATOR does just that; it recirculates coolant through a radiator (much like the radiator in your car).  It passively cools liquid by using a heat exchanger and cooling fins.


Do I need a chiller or a recirculator?

There is no simple rule to determine whether you need a chiller or a recirculator.  If you are welding in high production, welding aluminum, or other important or exotic applications, a chiller is the clear choice.  If the production rate is low, or the machine is used infrequently, a recirculator is probably fine.  Please contact us for details.


Chiller Sizing

A general rule for sizing a chiller is that, for every 100KVA of welder, you should have about a 1-ton chiller.  For example, if you want to cool 4 welders that are 100KVA each, you will need a 4-ton chiller.  If you want to cool a 300KVA machine, you will need a 3-ton chiller. See below for further sizing details.

Water Recirculators
Water Recirculators Water Recirculators Water Recirculators Water Recirculators
ProCool 2
(for 10-50KVA*)
(for 30-75KVA*)
(for 75-150KVA*)
(up to 300KVA*)
*These are generalizations.  Duty cycle, machine setup, welding material, and many other factors go into BTU calculation.

Chiller sizing, continued...
BTU calculations, with duty cycle taken into account

If you want a more accurate method for determining your chiller or recirculator size, you can use the formulas below.

To calculate BTU's per hour of a resistance welder:

Resistance Welding: BTU/hr = (welder KVA) * (duty cycle) * (.85) * (.6) * 3415 BTU/hr

Resistance Welding: BTU/hr = (Welder KVA) * (Duty Cycle) * (Eff Power Supply) * (Eff Heat Collection) * 3415

Eff. Power Supply: the % of power out to power input; typically 85%

Eff. Heat Collection: the % of heat absorbed by the chilling water; Varies 50%-75% est

To calculate duty cycle:
(weld time on) / (elapsed time) = duty cycle

Say you are averaging 4 welds per minute on a 100KVA welder with a weld time of 15 cycles (250ms).

duty cycle = [(number of welds) x (weld time, in cycles)] / 3600
duty cycle = [4 * 15] / 3600 = 0.016667 = 1.67%
BTU/hr = 100 * 0.8 * 0.016667 *0.6 * 3415 = 2732 BTU/hr