Club 80-90 Forums

Following on from an "aside" I wrote in the other "Heater cable gone caput !" thread, I wrote "my heater water valve cable is caput". This means I am stuck with my heater valve open. Ok in Winter, but not so "cool" in Summer So I got thinking about an easier way round fixing it.

I have often thought the heat control in our vans is a bit crude. To replace my cable will require a lot of work (dash out etc) so I think I can kill two birds with one stone here and fit an electrically operated water valve in the heater pipe, like this =



And have it controlled by a simple cab temperature monitoring and control circuit (which I can build) so it can be set to thermostatically control what ever temperature I wish

Been there! You would still be working with/against/in spite of the temparature control lag that results from throttling the hot water flow to the matrix.
Personally I would have the dash out and fit a new cable.

Ummm, the old hysteresis issue. How about making it semi analogue with a variable mark space ratio output to control the valve. Nah, maybe that is getting over complicated. Click, click, click, click, all the time

You need one of these to control dat ting... A PID controller..

"A proportional-integral-derivative controller (PID controller) is a control loop feedback mechanism (controller) widely used in industrial control systems. A PID controller calculates an error value as the difference between a measured process variable and a desired setpoint. "

Usually comes with a heavily rated (amps) power relay.
They are veery clever devices and not necessarily that expensive these days.

Your sort of job John I think. . Cracking solution if it all comes in on budget

Just For your info You don't need to remove the dash to do the cable. You'll loose some skin and wish your hands where smaller but it can be done. I think it took me a few hours. Make sure you buy a new clip to hold the cable to the heater valve. Coz mile was S£ag^d.