Central Heating downstairs will not turn off

[PRM64]

Hi all
I have a Valiant Thermocompact VU 242 / 1/E boiler that is situated in the garage. A couple of weekends ago I arrived home and found both the boiler and downstairs radiators were on although the thermostat and central heating timer was off. I turned the boiler off and re started but the radiators downstairs came on even though the timer was off and the thermostat was as far left as you could turn the dial.....

As of today the only was I can turn off the downstairs central heating is by turning off the boiler.

Upstairs works perfectly and is being controlled by the time and the upstairs thermostat.

I also have a thermostat in the garage, which I presume is frost, but I have no idea how this works...this is turned as far left as it can go as well.

I am not a great DIY / understander of such things, but I was wondering if anyone out there may be able to advise a remedy, before I call out British Gas or a heating engineer.

Hope all the above makes sense....Thanks in advance....P

 

[twgas]

1of two likely causes, frost stat is faulty (assuming its not freezing cold where you are) or downstairs heating valve is stuck on.

 

[PRM64]

1of two likely causes, frost stat is faulty (assuming its not freezing cold where you are) or downstairs heating valve is stuck on.

Thanks Mick, Is the heating valve something can be easily unstuck, I guess if it is simple I could have a go........Paul

 

[twgas]

If its not too badly seized then it would be easy for me, but I'm a heating engineer, I don't know how competent you are so cant say if you would be able to do it. Not all valves are un-seizable.

 

[PRM64]

Mick, totally incompetent would be a reasonable description of my engineering skills. Thanks for your advice....I will get someone out to fix...Cheers Paul

 

[twgas]

Get a heating engineer, not a plumber.