Heater bypass

[tuzza123]

I can see the point of heater bypass but surely making a bridge between the pipes before heater will affect the water flow when heater is on reducing heat output

[steamo]

You could have a valve switching water flow to either the bypass ot the heater matrix. Thats how it works in an old mini IIRC (normally a cable operated valve) hope it helps.

[tuzza123]

Thanks for info have solved problem as the heater have fitted blows into old Vw duct pipe I have made a flap to block output the nice bit is that it is still controlled by origional knob in cab .
I would post a picture but but cannot use this complicated method