Where is the motorised valve?

[KsMum]

We have a Flowmax Thermal Storage Cylinder (circa 1993) fitted with two pumps - situated in a airing cupboard upstairs. The system is operated using a Drayton LP241 programmer (also circa 1993), The Glow-worm Micron 40FF boiler is in the kitchen downstairs. Our problem is that the central heating will only come on when the hot water is programmed to come on. The CH seems to want to operate on the default times of the programmer - the rads become very hot at 4.30pm! The wall thermostat works - it will click if turned to indicate a temp of 15 degrees but will not turn on the heating unless the hot water is also on. The Drayton instruction sheet indicates that we should be able to operate HW and CH separately on a fully pumped and controlled system - which our plumber has confirmed we have. He thought the motorised valve might be faulty, but cannot find where it is. Is there one on this type of cylinder. Any help would be really appreciated.

Ks Mum

 

[Homesafe]

Usually in the cupbord next to cylinder or under the floor boards near it?

pics could help.

 

[swbjackson]

There isn't a motorised valve with a flowmax. The heating will only work when the hot water is on as the hot water program heats the thermal store and the heating pump draws it's hot water from this.

Have a look at http://www.range-cylinders.co.uk/pdfs/technical/flowmax.pdf

 

[KsMum]

Thankyou 'newgas' and 'swbjackson' for your answers. I have now read the link you suggested swb and indeed it does say you cannot have CH on without the HW being on. My son has lived in his house for 2 years or so and clearly the HW times have been altered which affected when the CH came on. He had not known this would affect the CH as the systems he has had in the past have operated independently. Wouldn't it be useful if this sort of information was written down by vendors when they sell you a place!!! Thanks again.

 

[JohnD]

but if you have a thermostat on the thermal store, and it is well insulated, surely it will stop calling for heat when up to temp, so you could leave HW on all day? Then, if you get a programmable room stat, you can set the times and room temps on that.

I am not a pro.