Heater Bypass

[Loubaruch]

Hedgehopper kindly pointed out that inserting a water shut off valve in the heater feed from the inlet manifold might not be prudent as it would prevent water circulation on warm up before the thermostat opens. A bypass pipe is supposed to be fitted that allows circulation to continue even if the normal Heater electric valve shuts off the supply to the heater. Following the water plumbing carefully my 96 500 does not appear to have any form of heater bypass and as far as I know it is as original and there are no signs of alterations. Where is the bypass located? Or were some cars not fitted with a bypass?

[Loubaruch]

Thanks very much fellows. I will reinstate my mechanical shut off valve in the feed from the inlet manifold as it did seem to work very well and allowed cool air to circulate.

[Loubaruch]

Thanks again for the cautionary warnings.

Had a word with my local TVR workshop manager who said that they had never seen a heater bypass on the later cars they have serviced, and they must have seen scores. Also he could not see a problem with fitting the mechanical valve as it is doing no more or less than the electric one when working properly. Thats good enough for me!