Hi Guys,
Got a problem with my heating at the moment in that the boiler is not switching off when the thermostat clicks off.
I think I've pinned it down to the motorised valve, which is a Drayton two-port with a ZA5 actuator. If I move the manual lever then release it the burner clicks off. I can also get it to click off sometimes by altering the thermostat to send on/off signals. After multiple attempts at this it will shut off, sometimes coming back on shortly after.
From what I've read, this sounds like there's something wrong with the actuator and for £40 odd, I thought I'd try fitting a replacement before calling someone out.
Does this sound right?
If so I have a question about fitting. My understanding is the valve is normally closed, and when it switches on, it both opens and tells the boiler to fire up. In the event of the actuator being removed from the valve, the valve would remain closed and the boiler would stay off.
If so, then why do the ZA5 instructions say to move the manual lever to the right before installation. Seems like this would have the actuator set in the open position, but the valve closed?
Many thanks!
Adrian.
Got a problem with my heating at the moment in that the boiler is not switching off when the thermostat clicks off.
I think I've pinned it down to the motorised valve, which is a Drayton two-port with a ZA5 actuator. If I move the manual lever then release it the burner clicks off. I can also get it to click off sometimes by altering the thermostat to send on/off signals. After multiple attempts at this it will shut off, sometimes coming back on shortly after.
From what I've read, this sounds like there's something wrong with the actuator and for £40 odd, I thought I'd try fitting a replacement before calling someone out.
Does this sound right?
If so I have a question about fitting. My understanding is the valve is normally closed, and when it switches on, it both opens and tells the boiler to fire up. In the event of the actuator being removed from the valve, the valve would remain closed and the boiler would stay off.
If so, then why do the ZA5 instructions say to move the manual lever to the right before installation. Seems like this would have the actuator set in the open position, but the valve closed?
Many thanks!
Adrian.