Hi All
I have a Potterton Suprima 50, installed with new build house since 2000, started to go into 'lock out' last week then eventually packed in all together. Took some advice from these forums and re-soldered all joints on the PCB, worked ok for a couple of days. Found out about the fiasco with 'Watchdog' on the BBC, called Potterton, there's an engineer popping out tomorrow (28/05/2007) free of charge to sort things out!
Anyway, I was intreagued to understand how my central heating works so I delved deeper into my system, I have the following:
Potterton Suprima 50
Sunvic Select 207 Programmer
Sunvic SD2701 3-port Unishare valve
Sunvic cylinder stat.
Drayton electronic room stat. (forget model but basically, 'ON' or 'OFF')
Sunvic WC 2202A junction box
I wanted to look into the wiring as I'm convinced the CH has always been on when the DHW was only needed (middle of summer and room stat not calling for heat).
I dug out the following drawing and checked it against my installation, it is wired exactly the same. I'm able to follow how the circuit works but can't understand how the room stat. demands heat from the boiler and pump.
My guess is that there are some clever bits of circuitry within the Sunvic SD2701 which involves a relay diverting power internally when the 'grey' wire becomes 'live'. When the 'grey' wire becomes 'live' a relay diverts 240 volts from the 'white' wire onto the 'orange' internally either when the cylinder stat. becomes 'satisfied' or 'HW OFF' is selected on the Programmer. This then allows a call from the room stat. to demand heat from the boiler and pump.
Hope this makes sense to someone?
I'm not a plumber but I'm curious to know how the circuit works.
Many thanks in advance for any shared knowledge.
DH
I have a Potterton Suprima 50, installed with new build house since 2000, started to go into 'lock out' last week then eventually packed in all together. Took some advice from these forums and re-soldered all joints on the PCB, worked ok for a couple of days. Found out about the fiasco with 'Watchdog' on the BBC, called Potterton, there's an engineer popping out tomorrow (28/05/2007) free of charge to sort things out!
Anyway, I was intreagued to understand how my central heating works so I delved deeper into my system, I have the following:
Potterton Suprima 50
Sunvic Select 207 Programmer
Sunvic SD2701 3-port Unishare valve
Sunvic cylinder stat.
Drayton electronic room stat. (forget model but basically, 'ON' or 'OFF')
Sunvic WC 2202A junction box
I wanted to look into the wiring as I'm convinced the CH has always been on when the DHW was only needed (middle of summer and room stat not calling for heat).
I dug out the following drawing and checked it against my installation, it is wired exactly the same. I'm able to follow how the circuit works but can't understand how the room stat. demands heat from the boiler and pump.
My guess is that there are some clever bits of circuitry within the Sunvic SD2701 which involves a relay diverting power internally when the 'grey' wire becomes 'live'. When the 'grey' wire becomes 'live' a relay diverts 240 volts from the 'white' wire onto the 'orange' internally either when the cylinder stat. becomes 'satisfied' or 'HW OFF' is selected on the Programmer. This then allows a call from the room stat. to demand heat from the boiler and pump.
Hope this makes sense to someone?
I'm not a plumber but I'm curious to know how the circuit works.
Many thanks in advance for any shared knowledge.
DH