just need to quickly check something if possible... when turning hot water ON from the programmer the 3 port mid is already open to H/WATER? So SHOULD the orange wire be live??
orange wire on 3 port mid?
- Thread starter londonboy123
- Start date
the orange will be live when calling for hw.
yeah thats what i thought, it is live and 230v but the motor is just not energised as it is already in the open position (port A is blocked).
Well said.
I have lost count of the number of contributors who think that the boiler is always turned on by the orange wire.
the cyl stat call (1) usually puts the power to pump and boiler (as mid pos valve is already open to hot water i guess.
The Orange wire is only life in the heating mode
In the Y plan system, when Hot Water is called for, power to the Boiler is provided directly
from the cylinder thermostat, the valve is not energised. When Heating is called for, the
Heating ON wire (White) is energised and the valve will motor to micro-switch #1 and stop
in a mid-position.
If the Hot Water is then turned off, (either by the programmer or cylinder thermostat) the
Hot Water OFF wire (Grey) is energised. If there is still a demand for Heating the valve
will then motor towards the Heating Only position and switch micro-switch #2, which then
puts a 240V supply onto the boiler. The orange wire only has a 240V supply from the
valve when it is in the Heating Only position i.e. 240V on White & Grey wires.
When heating is satisfied, from the Heating Only position, 50 - 150V (voltage can vary
according to the supply) will remain on the orange wire and the valve will continue to be
energised and warm to the touch. Switching ON Hot Water or turning OFF at the mains
will de-energise the valve and it will spring return back to the Hot Water Only position.
In the Y plan system, when Hot Water is called for, power to the Boiler is provided directly
from the cylinder thermostat, the valve is not energised. When Heating is called for, the
Heating ON wire (White) is energised and the valve will motor to micro-switch #1 and stop
in a mid-position.
If the Hot Water is then turned off, (either by the programmer or cylinder thermostat) the
Hot Water OFF wire (Grey) is energised. If there is still a demand for Heating the valve
will then motor towards the Heating Only position and switch micro-switch #2, which then
puts a 240V supply onto the boiler. The orange wire only has a 240V supply from the
valve when it is in the Heating Only position i.e. 240V on White & Grey wires.
When heating is satisfied, from the Heating Only position, 50 - 150V (voltage can vary
according to the supply) will remain on the orange wire and the valve will continue to be
energised and warm to the touch. Switching ON Hot Water or turning OFF at the mains
will de-energise the valve and it will spring return back to the Hot Water Only position.
Only because it is connected to the same terminal as the boiler!
Read Mid-position valve working and Diagnostics
as you say always live. but when on heating the orange is live from the mot valve to power the boiler and pump.
but in hw the power to boiler and pump comes from the cyl stat and only makes the orange live cause its in the same terminal as the cyl stat.
What is the point in giving an answer which, although correct is "economical with the truth"?
Anyone looking at the wiring of a Y-plan would realise that the voltage at the terminal to which the orange wire is connected would read 230v when the boiler was running as the same terminal also provided power to the boiler and, sometimes, the pump. So you have to read behind the question to find out what the OP was really asking, which is: "will the orange wire be receiving 230V via the switches in the motorized valve when the valve is in HW only?"
To which the indisputable answer is NO, a thousand times NO!
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