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Everything else / DIY water chiller - reading suggestions?
« on: July 15, 2021, 08:34:35 PM »
This year's fires and record heat have forced my to re-consider adding a water chiller to my in floor heat system for some modest cooling. Since the house is only 1100SF and superinsulated, and based on tests with my neighbor's home using well water, about 12,000 BTU would just do it, and that's within my daytime PV/inverter power of 1500W at 230VAC. I only need to pull out about 4 degrees per day, my hot day heat gain which I normally can overcome with just opening windows at night. But not when smoky or clouds hold in the heat at night.
I've read all about refrigeration systems and understand the principles, but lack hands on experience.
Water chillers are grossly overpriced for their BTUs, using titanium clad heat exchanger assuming corrosive, oxygenated water. My heating system is closed loop, so that's a non-issue and so I'd like to use a tube in a tube or stainless plate type exchanger between refrigerant and the in-floor, recirculated water. This will require new tubing on the low pressure side.
I'd love to find a book or other resource so I can learn how to estimate the amount of refrigerant required after evacuating the assembled system. I would prefer to use a non-inverter mini split outside unit, or modified evaporator window AC unit with 3/8 pipe run of about 6 feet to the plate heat exhanger. Issues I need to learn include when to purge after brazing, how to calculate refrigerant charge and lubricant, how to adjust the evaporator valve for optimal efficiency.
Any suggestions for good texts or websites?
BruceM
I'm looking for the practical experimenter's guide to homebrew refrigeration, I suppose.
I've read all about refrigeration systems and understand the principles, but lack hands on experience.
Water chillers are grossly overpriced for their BTUs, using titanium clad heat exchanger assuming corrosive, oxygenated water. My heating system is closed loop, so that's a non-issue and so I'd like to use a tube in a tube or stainless plate type exchanger between refrigerant and the in-floor, recirculated water. This will require new tubing on the low pressure side.
I'd love to find a book or other resource so I can learn how to estimate the amount of refrigerant required after evacuating the assembled system. I would prefer to use a non-inverter mini split outside unit, or modified evaporator window AC unit with 3/8 pipe run of about 6 feet to the plate heat exhanger. Issues I need to learn include when to purge after brazing, how to calculate refrigerant charge and lubricant, how to adjust the evaporator valve for optimal efficiency.
Any suggestions for good texts or websites?
BruceM
I'm looking for the practical experimenter's guide to homebrew refrigeration, I suppose.