1987 240 Estate 2.3 Heater is either on or off Help!!

Hello all

I have 240 2.3 estate which I bought as a parts chaser while rebuilding a Spitfire (Triumph not Supermarine). It is probably the best car I have owned over the last 20 odd years and I am going to keep it, The heater on this car is either off or on with no variable adjustment for the temp.

Is this a regular problem with theese cars? if so what is the usual fix for this problem?

Any help would be much appreciated.

Thanks

Chris

[Clifford Pope]

Older cars (not sure of dates) used a metal heater valve with a thermostat controlled by a sensor on a capiliary tube poking into the heater box. Later ones (and the only replacement available) used a plastic valve with no thermostat.
It sounds as if your thermostat has stopped working.I did have one where the bulb had been left outside the heater casing, so it never picked up that the heater was on. Easily done if someone has had the heater apart - you have to split the casing to get the bulb in, but have to take the unit out to get at it.
Why the plastic kind doesn't need a thermostat I don't know - it seems that the degree of adjustment must be better so simply restricting the flow is good enough. They are a pig to replace because the hoses are usually bonded on and it is easy to crush the heater pipes with enthusiastic use of plers and screwdrivers.