Mid position valve problem

[jakeh83]

Im trying to diagnose a problem y plan system that won't go to mid position but will go onto heating or dhw only, would that indicate a faulty valve or programmer issue? It's a Drayton ma1 mid position valve

 

[AMGasServices]

Do you have access to a multi meter?

Also how’s your knowledge with electrics?

 

[MHG]

With stats calling for heat the valve will go heat only or Dhw only I would say valve u/s as the programmer appears to be working ok as previous comment check with multimeter to confirm

 

[jakeh83]

Do you have access to a multi meter?

Also how’s your knowledge with electrics?

Yes I do it's a job I'm going back to been nothing but a pain!

 

[AMGasServices]

Check the voltage on the orange and white wire you should be getting 240v. For heating and hot water.

 

[MHG]

3 Port Valve Operation
The valve itself has three plumbing connections - in, out A and out B.
Regardless of other settings, at least one of the outlets is always open, so it is always possible for water to flow through the valve.
Outlet A is normally connected to the central heating, with B used for hot water.

Electrically, the valve has 5 wires:

• Green/Yellow, Earth - connected to the metal body of the valve.
• Blue, Neutral - internally connected to the neutral side of the motor.
• White, Live in 1 - Activates the motor inside the valve to select either AB (both) or A (heating)
• Grey, Live in 2 - Used with the White wire to select outlet A only (heating)
• Orange, Live Out - this is used to switch the boiler on when the valve is at position A.

No power
With no power applied, the spring holds the valve in position B, so water only flows to the hot water cylinder.

Power on White only
The motor will move the valve to the mid position AB, so both heating and hot water are selected. Internal switches and other components ensure the motor is held at this mid point.

Power on White and Grey
Here the motor will move to position A (heating only). When it gets there, an internal switch connects white and orange together, and this output is used to activate the boiler.
This results in a noticeable delay when switching on heating only, as the motor has to move the valve from B to A. This takes several seconds.
Hope this helps

 

[jakeh83]

3 Port Valve Operation
The valve itself has three plumbing connections - in, out A and out B.
Regardless of other settings, at least one of the outlets is always open, so it is always possible for water to flow through the valve.
Outlet A is normally connected to the central heating, with B used for hot water.

Electrically, the valve has 5 wires:

• Green/Yellow, Earth - connected to the metal body of the valve.
• Blue, Neutral - internally connected to the neutral side of the motor.
• White, Live in 1 - Activates the motor inside the valve to select either AB (both) or A (heating)
• Grey, Live in 2 - Used with the White wire to select outlet A only (heating)
• Orange, Live Out - this is used to switch the boiler on when the valve is at position A.

No power
With no power applied, the spring holds the valve in position B, so water only flows to the hot water cylinder.

Power on White only
The motor will move the valve to the mid position AB, so both heating and hot water are selected. Internal switches and other components ensure the motor is held at this mid point.

Power on White and Grey
Here the motor will move to position A (heating only). When it gets there, an internal switch connects white and orange together, and this output is used to activate the boiler.
This results in a noticeable delay when switching on heating only, as the motor has to move the valve from B to A. This takes several seconds.
Hope this helps

Great stuff mate