Szia,

>  There is a diagram on p. 80.16 of the Bentley manual, and that's probably
> the only mention of it.

My Bentley ends at 80.14 :-(
I don't think that somebody had pulled it out

> There is no cable for the valve; You leave the valve
> on in cooler months when you expect that you might want heat.

I see, this was my other idea

> But sometimes people have by-passed the valve/heater entirely because either the valve or the heater
> core was leaking.

OK, I'll see if someone by-passed the heater. Thanks for the reply.

ll@