Hi,
We moved into a property a few months ago. Sealed system - Alpha SY24 system boiler and Heatrae Sadia Megaflo. We've had some problems with the Alpha, with the pressure rising when the CH was on.
To cut a long story short, boiler man is coming later this week to fit an new external expansion vessel.
However - I've just noticed that the main radiator in the master bedroom is getting slightly warm when the HW is running. The return pipe that goes through the HW cylinder is T'd into the return pipe for the CH. Above that connection point there is an isolation valve (simple screw one), and above that the HEP20 pipe that leads from the master bedroom. There's a similar isolation valve connecting the HEP20 that goes into the master bedroom.
I've found that there's a flow arrow on the valves. For the Flow pipe it's pointing UP, but for the Return it's also pointing UP, not DOWN. When the CH is on, the flow pipe gets really hot, but the return pipe below that isolation valve never gets more than warm.
It would seem to me that the isolation valve on the Return is the wrong way around. I'm assuming that the pressure above the valve is eventually sufficient to overcome the valve ? and could it be that this is what is causing the pressure rise in the boiler, rather than a potentially knackered expansion vessel (as there is no evidence of leaking).
Could it be that draining the system and turning this valve around (preferably replacing it with a new version) might cure the problem ?
Also - should the cylinder Return just be T'd into the CH Return, or should there be something there ?
We moved into a property a few months ago. Sealed system - Alpha SY24 system boiler and Heatrae Sadia Megaflo. We've had some problems with the Alpha, with the pressure rising when the CH was on.
To cut a long story short, boiler man is coming later this week to fit an new external expansion vessel.
However - I've just noticed that the main radiator in the master bedroom is getting slightly warm when the HW is running. The return pipe that goes through the HW cylinder is T'd into the return pipe for the CH. Above that connection point there is an isolation valve (simple screw one), and above that the HEP20 pipe that leads from the master bedroom. There's a similar isolation valve connecting the HEP20 that goes into the master bedroom.
I've found that there's a flow arrow on the valves. For the Flow pipe it's pointing UP, but for the Return it's also pointing UP, not DOWN. When the CH is on, the flow pipe gets really hot, but the return pipe below that isolation valve never gets more than warm.
It would seem to me that the isolation valve on the Return is the wrong way around. I'm assuming that the pressure above the valve is eventually sufficient to overcome the valve ? and could it be that this is what is causing the pressure rise in the boiler, rather than a potentially knackered expansion vessel (as there is no evidence of leaking).
Could it be that draining the system and turning this valve around (preferably replacing it with a new version) might cure the problem ?
Also - should the cylinder Return just be T'd into the CH Return, or should there be something there ?
