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baker
02-02-2004, 09:08 AM
I am designing a water cooled air conditioner and want to use an automotive heater/defroster unit as part of the condenser setup. The unit is rated at 20,000 BTU but the wholesaler can't give me any information as to what this means.

Presumably there are industry standards for water flow rate, water temperature diff, air flow rate and air temperature diff.

Can anyone suggest what these values are likely to be?

baker
03-02-2004, 08:33 AM
Thanks, but the 20000 BTU rating is on an automotive heater, where hot engine water heats the cabin air.

Jaguars used to have thermostats that were a lot lower than Fords (160F vs 190F from memory), so a heater in a Jag would transfer less heat than the same unit in a Ford (when they weren't the same company).

I would assume that the heater manufacturers rated their units to some standard, so that vehicle manufacturers could select the right model. I am just trying to get some idea of what these standard conditions would be. I would assume that the temperature differences would be a lot higher than what is normally found in refrigeration.

chemi-cool
03-02-2004, 04:27 PM
hi mark,

if automotive air-condition is your problem, Karl Hofmann is your man!

chemi