Drayton Mid Position Actuator Issue

[BugalowDave]

Hi I'm after some help,

A recent problem has risen with my HW and central heating system and not sure if it's a mechanical or electrical problem.

On the timer I have the HW system come on in the morning and a hour later have the CH come on and to stay on for the rest of the day, however when the HW goes off the boiler does not keep the CH system going and gradually the radiators go cold.

I've checked to see what the actuator is indicating through this process, on physically switching the HW on the actuator indicator goes to W then on switching the CH on the actuator indicator goes to M then I switch the HW off leaving the CH on (at the timer) and the actuator remains on M and the boiler does not continue to work for the heating, If I turn off and then on again to the electrics completely to the whole system the actuator indicator then moves to H and the boiler then kicks in for the heating.

So can someone advise is it the actuator that needs replacing or is to do with the electric/control system not giving the actuator the right signal to move? I want to find out before spending money on it.

Thanks in advance for any advice.

 

[Johntheo5]

Can you do the following tests,
1 HW programmed on but cylinder stat turned down to minimum, CH programmed on and roomstat calling for heat, does the valve move to the CH position?. If not do test 2.
2 HW programmed off, CH programmed on and roomstat calling for heat, does the valve now move to the CH position?.

 

[BugalowDave]

Hi Johntheo5,

Thanks for replying, I did test one twice and it did move to CH I also did test 2 and it did again move to CH on returning the cylinder stat to the desired temperature and switched the HW & CH on the valve then moved to M (mid point) I then switched the HW off (CH on) and the valve moved back to CH, If I scratch my head further I'll get splinters.

 

[Johntheo5]

Hi I'm after some help,

A recent problem has risen with my HW and central heating system and not sure if it's a mechanical or electrical problem.

On the timer I have the HW system come on in the morning and a hour later have the CH come on and to stay on for the rest of the day, however when the HW goes off the boiler does not keep the CH system going and gradually the radiators go cold.

Saw your answers above, strange allright, when you say the HW goes off, (and the valve fails to move to the CH position), is this when its programmed off or when the cylinder stat switches it off?

If you do another test....with both CH&HW requested, Programme off the HW, does it move to CH only, and again with both CH&HW requesred and you turn down the cylinder stat does it move to Ch only?

I've checked to see what the actuator is indicating through this process, on physically switching the HW on the actuator indicator goes to W then on switching the CH on the actuator indicator goes to M then I switch the HW off leaving the CH on (at the timer) and the actuator remains on M and the boiler does not continue to work for the heating, If I turn off and then on again to the electrics completely to the whole system the actuator indicator then moves to H and the boiler then kicks in for the heating.

So can someone advise is it the actuator that needs replacing or is to do with the electric/control system not giving the actuator the right signal to move? I want to find out before spending money on it.

Thanks in advance for any advice.

 

[CBW]

Sounds like an electrical fault. What happens if you try heating only?

 

[stem]

On the timer I have the HW system come on in the morning and a hour later have the CH come on and to stay on for the rest of the day, however when the HW goes off the boiler does not keep the CH system going and gradually the radiators go cold.

When you say "when the HW goes off" are you saying:

a) Switched off by the hot water cylinder thermostat because the water inside the cylinder is now hot? or

b) Because the programmer has switched off the hot water?

 

[Johntheo5]

When you say "when the HW goes off" are you saying:

a) Switched off by the hot water cylinder thermostat because the water inside the cylinder is now hot? or

b) Because the programmer has switched off the hot water?

The "another" test I suggested in post#4 might show if its a fault with the cylinder stat satisfied contact 2 or a fault in the HW OFF contact in the programmer?.

 

[BugalowDave]

Thanks for the replies it's become academic at the moment as I tried to move the indicator tab and it snapped so I'll be replacing the whole actuator if the new one has the same fault then I'll be calling a heating expert as it will then be beyond my limited skill, thanks for all the advice.