Troubleshooting motorized Valve?

[DanSig]

Hi and thanks for your time.

Currently have a problem with No central heating but loads of hot water. The motorized valve is a Honeywell 2 Port in the auto position. I switch this to manual and the heating starts working.

How can I troubleshoot this further?

Is this something I can replace myself?

Thanks in advance for your help.

Dan

 

[hi-spec plumbing heating]

would say the motor has gone.
check for power at the motor when calling for heat.

yes you can change it.

 

[DanSig]

When I take the valve off of manual it rolls back to Auto on it's own so I presume the valve is working ok, so it must be the motor.

What's the best way to troublshoot the motor, and check for power to it etc.

Thanks again.

Dan

 

[hi-spec plumbing heating]

theres two wires to the motor use a multi meter to check for volts to to motor

 

[Space cat]

Are you sure it's the valve that's faulty? It won't open without power. In a typical system this originates at a programmer/controller then passes through the room thermostat before it gets to the valve. The thermostat is where I'd start because the terminals are usually easy to get to. If you have power on both sides when it's on, that's when you start blaming the valve - or have you tried this already.

If you have no power on either side of your room stat you can start blaming the programmer.

 

[DanSig]

When I push the valve to "Man Open" the heating kicks in.
Are you saying that without power the valve would not open even manually?

Cheers,

Dan

 

[dal5band]

I thought the lever could be latched in the manual position ? to keep the heating going.

 

[DanSig]

Yeah I can latch the valve to manual and it works, so I presume this means that the valve isn't faulty. When I push it to the left without latching it automatically rolls back to the the right.

Does this mean the motor is working?

The problem is the heating does not come on unless I put it into manual.

Is this the motor? or the thermastat?

Cheers guys,

Dan

 

[hi-spec plumbing heating]

if you put the lever in man position and the heating works there is power from stat.

if you put lever in man position and it don't work there is no power getting to it.

you said your is working when lever moved.

 

[dal5band]

The most likely cause is that the actuator is not working (i'e' the motor unit). Normally, the actuator pushes the valve the same way as you are doing manually, it's only a spring that pushes back to the closed position. When you let go, the valve is moved to the closed position by a spring, the motor holds it open all the time it's on - that's why they burn out after about 10 years.

Make a note of the model number and get a new actuator, there will be instructions inside how to fit it, no plumbing required but you do need to do electrical connections. Make sure the boiler electric supply is fully isolated and double check.

 

[gas4you]

Putting the lever to manual will not activate the micro switch in the valve head to tell the boiler to fire. The room stat onlys controls the synchron motor. The grey wire, permanent live to microswitch, is what give the power to the boiler once valve has opened.

Personally I only ever change the complete head

 

[dal5band]

Yes - people refer to the "head" or "actuator" or "motor" mean the same thing - the box that sits on top of the brass valve.

Some people do refer to the actual little A/C motor inside the box but I've never opened one.