too much heat - problem
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From: Indianapolis, IN
too much heat - problem
I am going to start out the easy way - post for some help before I exhaustively Search. Actually, I have already searched a bit and read a few suggestions. But, today I have new conflicting/confusing data.
Problem - too much heat in the cabin, regardless of the temperature **** setting.
Possibilities, and some data from running Scanttol Test Outputs
1. Is there a hole in heat duct hose coming from the engine in the footwell. Have not pulled off the cover, but, the heat is coming from all of the vents. left and right, so I do not think it is just a simple leak from a hose on one side.
2. Mixing servos not closed. Interesting - Left side (which I thought was the hottest) servo is working during Test Outputs. Right side did not respond, but later, responded to the CLOSE test. So, this may be Part of the problem, but there is more data....
3. Rear blower comes on and stays on HIGH regardless of temperature setting. At least during the test tonight. I thought it should come on Low for heating. High for engine cooling. Per the system description, under High speed the differrential pressure dampers should close and divert the hot engine air to the wheel wells ?
4. Rear blower did not come on during Low Speed test on Scantool. Came on High Speed for test.
5. Left secondary blower did not come on during Scatool Test. Right fan came on. Fuse(s)? Relays? for these fans? are they controlled independently. I read about "amplifier" in the system description for the blower controls. ??
6. I have had intermittent blower responses, especially when using AC, and more so on speed setting 4. Seems to go from High to Higher, and at times runs faster but no more air coming out.
7. Had fault codes 31, 43, 45, 46 (I recall), that have something to do with the rear fan, I believe.
8. I am starting to think the key variable that so many things are linked to is the rear fan not always operating on low speed when it should.
9. Rear fan issues - one fuse? can the resister munted in the heat tube fail? which relay controls the fan?
10. So many things seemed to have happened all at once. I am wondering if the CCU is to blame? Just a week ago, the system was heating beautifully - one click up or down on the Temp **** brought an instant change.
If anyone can point me in the right direction for the search.
Problem - too much heat in the cabin, regardless of the temperature **** setting.
Possibilities, and some data from running Scanttol Test Outputs
1. Is there a hole in heat duct hose coming from the engine in the footwell. Have not pulled off the cover, but, the heat is coming from all of the vents. left and right, so I do not think it is just a simple leak from a hose on one side.
2. Mixing servos not closed. Interesting - Left side (which I thought was the hottest) servo is working during Test Outputs. Right side did not respond, but later, responded to the CLOSE test. So, this may be Part of the problem, but there is more data....
3. Rear blower comes on and stays on HIGH regardless of temperature setting. At least during the test tonight. I thought it should come on Low for heating. High for engine cooling. Per the system description, under High speed the differrential pressure dampers should close and divert the hot engine air to the wheel wells ?
4. Rear blower did not come on during Low Speed test on Scantool. Came on High Speed for test.
5. Left secondary blower did not come on during Scatool Test. Right fan came on. Fuse(s)? Relays? for these fans? are they controlled independently. I read about "amplifier" in the system description for the blower controls. ??
6. I have had intermittent blower responses, especially when using AC, and more so on speed setting 4. Seems to go from High to Higher, and at times runs faster but no more air coming out.
7. Had fault codes 31, 43, 45, 46 (I recall), that have something to do with the rear fan, I believe.
8. I am starting to think the key variable that so many things are linked to is the rear fan not always operating on low speed when it should.
9. Rear fan issues - one fuse? can the resister munted in the heat tube fail? which relay controls the fan?
10. So many things seemed to have happened all at once. I am wondering if the CCU is to blame? Just a week ago, the system was heating beautifully - one click up or down on the Temp **** brought an instant change.
If anyone can point me in the right direction for the search.
Last edited by DWS964; Oct 19, 2009 at 09:08 PM. Reason: update