Syncron motors

[wat5190]

My Syncron motor stays powered up even when the central heating is switched off at the timer, hot water off as well. Is this a timer fault i have a siemens RWB9 if you turn the main power off at the boiler it shuts everything down and the motorised valve returns back to hotwater setting ????? Any help out there

 

[danielp]

well whats happening for you to be looking at it and motorized valves have a permanent live that dont come from the programmer

 

[doitmyself]

motorized valves have a permanent live that don't come from the programmer

Zone valves with an auxiliary switch have a permanent live, but mid position valves are fed from the room stat, cylinder stat or programmer HW OFF.

 

[wat5190]

Re: Syncron motor staying LIVE help help help

The motor shouldn't stay powered up when the heating is turned off, you can hear it buzzing and get extremly hot. when the central heating turns off the motorised valve should lose its power supply and the valve should return to the hot water position. but that is not happening i am having to turn the main supply to the boiler then the motor returns the valve back to hotwater. Why is power supply staying to the motor?????????????????????

 

[doitmyself]

Re: Syncron motor staying LIVE help help help

The motor shouldn't stay powered up when the heating is turned off, you can hear it buzzing and get extremly hot. when the central heating turns off the motorised valve should lose its power supply and the valve should return to the hot water position. but that is not happening i am having to turn the main supply to the boiler then the motor returns the valve back to hotwater. Why is power supply staying to the motor?????????????????????

From what you say, the valve is working correctly.

If a mid-position valve is in CH ONLY position the grey and white wires have 240v on them. It is the grey wire which supplies the motor with power, via one of the switches, to move it to the CH ONLY position. When CH is satisfied and the room stat clicks off, the white wire drops down to 0v, but the grey wire continues to have 240v on it, so the valve stays in the CH ONLY position.

As it is only a 6W motor, the current drawn is negligible, though the valve may stay warm.

Noise may suggest that the motor or one of the switches is on its way out.

You can get replacement motors or complete actuators, unless the valve is very old.

Turning the power off, or turning HW ON will set the valve back to its default HW position.

 

[wat5190]

I am sure that when the central heating switchs off it used to return back to the hotwater position, and not stay powered up all the time. I fitted a complete new 3 way valve because my old one, the motor had burnt out.
If ure right in what you say when my heating turns off at 8am in the morning the motor stays powered up untill the heating comes back at 5pm when i get in from work, but i find it gets really hot just worried it getting too hot and setting on fire lol.

 

[stevetheplumber]

I am sure that when the central heating switchs off it used to return back to the hotwater position, and not stay powered up all the time. I fitted a complete new 3 way valve because my old one, the motor had burnt out.
If ure right in what you say when my heating turns off at 8am in the morning the motor stays powered up untill the heating comes back at 5pm when i get in from work, but i find it gets really hot just worried it getting too hot and setting on fire lol.

when there is no call for heating or hotwater there should be no power to the valve and valve rests at hot water only position

 

[wat5190]

So why is mine staying powered up any ideas???? stevetheplumber

 

[doitmyself]

when there is no call for heating or hotwater there should be no power to the valve and valve rests at hot water only position

It all depends on where you start from!

If you start with power off, the valve is in the rest position, port B (HW open). Turning either CH or HW ON at the programmer has no effect on the valve. Turn HW stat up has no effect on the valve, but it sends 240V to the boiler, which then lights.

If we now turn CH stat up the white receives 240V, motor turns, first switch operates and the valve is held in to mid position. Power to the boiler is still obtained from the HW thermostat.

When HW is satisfied, or turned off, 240V goes to the grey wire. This allows the motor to continue from mid-position to port A (CH) open. The second switch operates and the boiler receives its 240V via the white wire.

When CH is satisfied or turned off 240v drops from the white wire and the boiler goes out. BUT the valve still stays in the CH (port A open) position as the two internal switches are not in their rest position. The attached diagrams may help.