Barry Wolk
09-02-2021, 04:52 PM
There was much discussion about the HVAC systems. Elmer kept a diary, which is full of information.
They really wanted dual controls for the dual heater core system, but found one basic principal will always win out, water, like electricity, follows the path of least resistance. Instead of separate controls they opted for a single thermostat in the left duct, right after the heater core. It is cable controlled from the console and opens a vacuum port on demand. That vacuum signal is sent to both hot water valves that open, pushing hot water from the output side of the water pump to each core. The return lines from each core go to the suction side of the water pump.
The problem is that if you have you have a valve that's 5 gallons a minute and the other one 10 gallons a minute, no water will flow through the 5 gpm core, and you'll get no heat. As everything else about the boutique manufacturer the testing of fit and finish was left to the supplier to perform. It appears they needed batches that were tested and paired up, and that was left for the supplier to test. If your car is not performing as designed and I'm sure many valves have been replaced in 60+ years it not likely flowing the same. Simple test. (2) 5 gallon buckets, two hose connections hooked to the same water source, and one source of vacuum for both valves. Stop the flow when one bucket fills and measure the difference. I'm not sure what the tolerance was, but better knowing this than chasing a gremlin forever.
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They really wanted dual controls for the dual heater core system, but found one basic principal will always win out, water, like electricity, follows the path of least resistance. Instead of separate controls they opted for a single thermostat in the left duct, right after the heater core. It is cable controlled from the console and opens a vacuum port on demand. That vacuum signal is sent to both hot water valves that open, pushing hot water from the output side of the water pump to each core. The return lines from each core go to the suction side of the water pump.
The problem is that if you have you have a valve that's 5 gallons a minute and the other one 10 gallons a minute, no water will flow through the 5 gpm core, and you'll get no heat. As everything else about the boutique manufacturer the testing of fit and finish was left to the supplier to perform. It appears they needed batches that were tested and paired up, and that was left for the supplier to test. If your car is not performing as designed and I'm sure many valves have been replaced in 60+ years it not likely flowing the same. Simple test. (2) 5 gallon buckets, two hose connections hooked to the same water source, and one source of vacuum for both valves. Stop the flow when one bucket fills and measure the difference. I'm not sure what the tolerance was, but better knowing this than chasing a gremlin forever.
23373
23374
23375
23376
23377