Actuator Valve (or something else?)

[llwynygan]

I have a problem with my heating system (indirect unvented - with a cylinder). In order for the hot water to be heated my central heating needs to be on. If the central heating is not on (and the boiler is already fired up) the boiler does not fire up and heat water for the hot water cylinder. This is a real pain as it means we have to force the central heating to be on to get any hot water.

I have come across a Drayton zone actuator valve in the airing cupboard and wonder if this could be faulty? Or something else?

Other info that may be relevant is that the central heating has 2 zones - upstairs and downstairs - each controlled with their own thermostat and timing panel.

 

[SJB060685]

So you have 3 two port valves?

 

[llwynygan]

So you have 3 two port valves?

I am sorry I don't know what you mean. In the airing cupboard all I can see is one thing labelled "zone valve actuator".

 

[SJB060685]

Can you take a picture of the airing cupboard so we can see the setup please?

 

[llwynygan]

Here is the airing cupboard. The "zone valve actuator" that I can find is circled in yellow.

 

[SJB060685]

Ok. That I assume is the HW two port zone valve. I suspect the problem lies within this, unfortunately you're going to need a suitable heating engineer with an electrical multimeter to run a few tests.

 

[llwynygan]

I have a plumber coming next week. If the actuator valve is a potential cause I would like to have a new one in hand that he could fit. It is worth buying a better one - I have seen that Drayton ones are not the most reliable. If so, what do you suggest?

 

[SJB060685]

I always used Honeywell valves but as with any manufacturer, nothing lasts forever. However I do agree with you, Drayton seem to be more problematic.
If you decide to purchase one that's your choice, however I personally would really want to do some checks first.

 

[llwynygan]

I always used Honeywell valves but as with any manufacturer, nothing lasts forever. However I do agree with you, Drayton seem to be more problematic.
If you decide to purchase one that's your choice, however I personally would really want to do some checks first.

I will only get one if I can definitely return it for full refund! Is there any particular model numbers or specification I need to look for?

 

[SJB060685]

Just a standard normally closed Honeywell two port valve. Get it with 22mm tappings, I assume the copper pipework is 22mm?

 

[llwynygan]

Just a standard normally closed Honeywell two port valve. Get it with 22mm tappings, I assume the copper pipework is 22mm?

Probably is 22mm - not home now so cannot check. Will post here when resolved. Thx for your help.

 

[ShaunCorbs]

https://www.NoLinkingToThis/p/drayton-za5-679-2-2-port-motorised-valve-22mm-22mm-compression/32455

Might not even need to drain down depending on the body

 

[SJB060685]

First and foremost Shaun the head needs to be proved the fault, I suspect it is but need to be sure. The OP said he's not a fan of Drayton as well, hence why I suggested Honeywell. My experience with Drayton is not the best to be honest.