CH only works if HW is on too

[jkb1976]

I have an oil fired Trianco Eurostar external boiler connected to a Drayton HW cylinder, via a Lifestyle timer. The whole system is only about 2 years old.

Problem is that, when the CH timer is in the 'on' position, the CH won't actually come on unless the HW is set to come on as well (it will however come on if the HW's timer control is advanced to 'on' manually). As soon as the HW timer is off the heating goes off too. Not a massive problem but obviously this means burning oil to heat water when it's not actually needed.
Any ideas what the problems could be ? I am a bit of a thicko when it comes to this kind of thing and just wondering if its a simple problem that could be fixed without calling an engineer.
Cheers.

 

[nickso]

it could be configured/wired to perform like this. this was popular some time ago and i wouldnt really expect a new system to be set up like this......i know sod all about oil systems though so maybe its that

if you have a heating and a hW valve and both are wired properly to the boiler then it could be the clock is in the wrong mode.

you can change it at the back of the clock.

edit.......now thinking about it it cant be the clock as pushing the heating on if its wired right would fire it up. its more likely the endswitch in your heating valve hasnt been wired up. the clock mode would still need to be changed after you wire it up right though.

 

[gas4you]

have you got a 3 port valve or two 2 port valves?

 

[jkb1976]

Thanks both for your replies. This is a recent problem so unlikely its got anything to do with wiring etc as nothing has been touched.

I've got 2 2 port valves.

Don't know if its relevant but a couple of weeks ago I had a problem with the boiler locking out and it would only fire up again after pressing the reset switch (and after a certain (decreasing) amount of time it would lock out again until the reset switch was pressed again). Eventually the problem was solved after replacing the solenoid vavle. Could this be anything to do with the current problem?

Cheers

 

[nickso]

ok....now we know more

if it is wired up right the its more likely its the microswitch on the CH valve that is faulty or the valve isnt opening far enough to hit the microswitch.

 

[gas4you]

agree with nickso. Change the ch valve head if no wiring has been touched.

 

[jkb1976]

Thanks for your help guys - much appreciated.

 

[nickso]

i wouldnt chnge the head......try to repair it first.

seized motor
seized shaft
microswitch burnt out

all can be repaired.