Theben Ramses 701 thermostat

[Tigger90]

I have a Ramses 701 thermostat that is about 20 months old and it does not appear to be working correctly.
The drayton Tempes 7 heating controller is schedulled to be off at the moent, bu the radiators are still pumping out heat. I have turned the Ramses right down to 14 degrees, the lowest ettling it will turn to and nothing is happening.

Could it be that the thermostat is faulty?
I have turned all the TRV's down, the rad in the hallwall does not have one so is happilly chucking out loads of heat!

Thanks

 

[D_Hailsham]

If the timer says the heating is off, the thermostat will not be the problem.

Can you give more details about your system components:

Make and exact model of boiler;

List all other components with make and model.

 

[Tigger90]

I have a Heatstor 300litre 18 kw boiler
A Drayton Tempus Seven controller
and the Ben thermostat
The hall way rad does not have a trv, but all the others do.

 

[D_Hailsham]

I have a Heatstor 300litre 18 kw boiler, a Drayton Tempus Seven controller and the Ben thermostat.

Is the Heatstor is an electric boiler? If so, who makes it? The only info I can find is from a firm in the Channel Isles.

If it is electric, you might be better asking on the Electrical Forum.

 

[Tigger90]

Hi, yes the bolier is electric and made in Guernsey, Channel Islands by DHS. It uses the cheap rate electric.

 

[D_Hailsham]

Hi, yes the bolier is electric and made in Guernsey, Channel Islands by DHS. It uses the cheap rate electric.

At 18kW and 240Vac the current drawn will be about 75A, which is more than any domestic timer and thermostat can carry, so there must be a control box attached to the boiler with relays in it.

The cause of the problem will probably be that contacts in either the timer, thermostat or the control box have welded together.

I think you need to contact the installer or the manufacturers.

 

[gasbanni]

Has it ever worked properly ?
if it has then I wouldnt suspect the thermostat but the timer.
Its probably wired up through contactors or it should be. you should be able to hear the contactors making and breaking when a demand is put on the boiler its probably best to get a professional in.

 

[Tigger90]

Thanks for the advice.
I got the local electric company in and it turns out the boiler should have been recalled by DHS, the elements should be 2x3kw x 3 = 18kw but mine has 2x4 x 3 = 24kw! There was too much load on it and one of the relay was permantly tripped and one of the wires was also a little burnt out.

But the problem I called them out for - the heating was coming on when it liked when it shouldn't have, it turns out the valve was sticking. A new valve has been fitted and all sorted now.

DHS, the boiler suppliers are coming in the new year to change my elements, they didn't want to fix it right on Christmas just in case I had any further problems...

Other than that yes, the boiler works really well, loads of hot water and heating and miles better than the gas heating and hot water I used to have.