Sunvic Actuator - Not Switching - Manually Setting Help

[roverblue]

Hi there,

I have one of these removable actuators on my port valve in the airing cupboard..

http://www.toolstation.com/shop/Hea...ic+23+Port+Actuator+2+Port/d230/sd3232/p45139

I noticed over the last few days the radiators haven't been coming on but the water has. This has also come with bubbling or water noises from the hw cylinder.

It sounds daft but if i give the actuator a mild thump it starts to whirr and then the heating comes on, today even a thump wont fix it

I am guessing the motor has gone so took it off for the time being. I am left with a half moon looking valve that i can manually turn.

If I turn this to face the heating side fully is it ok to just leave it on this until I get around to being a replacement? I seem to get hot water and heating which is the right end result

My system is open vented, myson economist wm/40/50bf by the way. Its old and cr*p!

Thanks for your help,
RoverBlue

 

[stem]

From a plumbing point of view, there's no problem, however, inside the valve actuator there is a microswitch that is normally wired up to turn the boiler on when the valve operates. If the actuator doesn't operate neither will the microswitch, or the boiler (unless the hot water valve is open)

Having said that, you may get away with it if the actuator motor is just a bit weak and may work OK now there's no valve connected to it.

 

[roverblue]

Hi Stem,

Thanks for you reply its good to know I am not going to damage anything by manually setting this temporally.

I noticed last night that the hot water was no longer hot so it looks like that by turning this to face fully the CH port it isn't heating the water anymore.

If I leave this in the mid-position will it do both?

The good thing is that the heating for the first time since i moved in was nice and toasty these last few nights and the radiators hot to the touch. Could this be because in the past the motor wasn't operating correctly and not giving me full flow to the CH system when the water was hot enough?

Thanks for your advice,
Roverblue

 

[Hugh Jaleak]

The Sunvic valves have been known to be problematic, long term your best bet is probably to ditch it and replace with a Honeywell.

If you can get the valve to sit in mid position it should allow flow through to CH and HW, if as Stem says, you can get the actuator to sit in the correct spot to operate the boiler. Bear in mind both the roomstat and cylinder stats will be ineffective though with actuator disconnected from the valve.

 

[roverblue]

Hi,

thanks for getting back to me, the actuator is still calling the boiler as you suggest so its still firing OK. The motor is too weak to turn the valve though and I suspect has been for quite a while as the water has been boiling hot no matter what i did to the cylinder stat. Guessing it generally was stuck in mid-position, until somehow moving to HW only and getting stuck there.

If I get a new actuator will only a SUNVIC fit on the existing valve, if so does that mean replacing the 3 port and a new actuator?

Thanks for advice on Honeywell it seems they have a good rep. Stumbled across this list of horror stories for the SUNVIC when I was on Google so think I will stay away in future!

http://www.seered.co.uk/sunvic.htm

Cheers,
RoverBlue

 

[Hugh Jaleak]

Either replace the head, I suspect only a Sunvic actuator will fit (and work!), or change the entire valve. I replaced mine with a Honeywell, no issues since.