Back to the boiler, the right hand solenoid is the "FULL" gas and has to be open for anything to work at all.
The other two solenoids are in series with the gas supply and are 1/3 and 2/3 respectively.
On CH it works on 1/3 or 2/3 only.
On DHW it works on full ( thats 1/3 + 2/3 ) or 2/3 but NOT on 1/3 only.
Tony
The other two solenoids are in series with the gas supply and are 1/3 and 2/3 respectively.
On CH it works on 1/3 or 2/3 only.
On DHW it works on full ( thats 1/3 + 2/3 ) or 2/3 but NOT on 1/3 only.
Tony