another heater problem

nicnet · 11-21-2007, 07:15 PM

for sure it's not the VSV problem - I can see the valve is constantly open, yet the air temperature coming from the vent fluctuates from hot to cool and back.

I will try burping again (have done it twice now for 20 mins), but I don't think this is the problem. If collant was having trouble flowing through the heater matrix, then surely it wouldn't go suddenly from cool to hot to cool, but rather a gradualy change in temp as flow through the matrix became slower, then quicker (for whatever reasons).

And what about the perceived change noise and change in flow rate of the air, as it changes from hot to cool and back - as I said, it sounds to me like a damper issue - perhaps the Air Mix Control Damper. You can see it on top diagram in page AC13 of TSRM:
http://www.cygnusx1.net/Supra/Librar...aspx?S=AC&P=13

I wonder how to get to that damper - perhaps keep it forced open to see if heat stays constant? (will also burp again).

Nic

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11-21-2007, 07:15 PM	#4
nicnet Stock Join Date: Oct 2007 Location: finland Posts: 7	for sure it's not the VSV problem - I can see the valve is constantly open, yet the air temperature coming from the vent fluctuates from hot to cool and back. I will try burping again (have done it twice now for 20 mins), but I don't think this is the problem. If collant was having trouble flowing through the heater matrix, then surely it wouldn't go suddenly from cool to hot to cool, but rather a gradualy change in temp as flow through the matrix became slower, then quicker (for whatever reasons). And what about the perceived change noise and change in flow rate of the air, as it changes from hot to cool and back - as I said, it sounds to me like a damper issue - perhaps the Air Mix Control Damper. You can see it on top diagram in page AC13 of TSRM: http://www.cygnusx1.net/Supra/Librar...aspx?S=AC&P=13 I wonder how to get to that damper - perhaps keep it forced open to see if heat stays constant? (will also burp again). Nic