Hi, I have found many similar topics on google but don't seem to be able to find the exact same situation...
Recently our old potterton netaheat (semi-gravity) broke down so we have just had it replaced with a Worcestor Greenstar 12Ri and upgraded to fully pumped using a honeywell Y-plan pack. New cylinder and TRVs added to the radiators. Fairly small house with 6 rads.
The system is vented with an F&E tank in the loft, cylinder in the airing cupboard.
Before the switch we had problems with the F&E overflowing, with a constant dripping. which we assumed was just the ballcock on its way out (still think so). However after the upgrade things are a bit different.
When the hot water turns off, or when the pump turns off after the heating, there is a noise that sounds like water running through all the radiators, kind of sounds like a cracking noise almost the way it runs around the radiators, I had never knowingly heard it before the upgrade.
Initially this was also accompanied by a notable amount of water overflowing from the F&E pipe.
I called the installer back and he changed the ball valve so it doesn't overflow anymore. The water level in the F&E tank is much more sensible.
However the system is still venting some water, at least when the pump turns off. The noise still happens. I have tested this by turning the heating & hot water off and waiting in the loft a couple of minutes for the pump to turn off. I have put a bottle under the vent pipe to check exactly how much. The first time it was only maybe 1 - 3 fl. oz but I've left it there and will check how much is there tonight.
So I don't think this is meant to be happening... The system is installed in the correct order, boiler -> vent -> cold feed within 150mm -> pump -> 3 way valve. I don't think there's any bypass, but I see the boiler instructions say this is generally not needed.
Pump is a grundfos 15-50 and he left it on setting 3 when he left the first time. I have experimented with changing it down to 2 and its my impression that it seems to be less coming out, but I don't know if that is affecting it or not.
Should I worry about this? I believe this is generally bad for the system as it (probably fairly slowly at this rate) oxygenates the water? Any idea what the cause is?
Thanks
Matt
Recently our old potterton netaheat (semi-gravity) broke down so we have just had it replaced with a Worcestor Greenstar 12Ri and upgraded to fully pumped using a honeywell Y-plan pack. New cylinder and TRVs added to the radiators. Fairly small house with 6 rads.
The system is vented with an F&E tank in the loft, cylinder in the airing cupboard.
Before the switch we had problems with the F&E overflowing, with a constant dripping. which we assumed was just the ballcock on its way out (still think so). However after the upgrade things are a bit different.
When the hot water turns off, or when the pump turns off after the heating, there is a noise that sounds like water running through all the radiators, kind of sounds like a cracking noise almost the way it runs around the radiators, I had never knowingly heard it before the upgrade.
Initially this was also accompanied by a notable amount of water overflowing from the F&E pipe.
I called the installer back and he changed the ball valve so it doesn't overflow anymore. The water level in the F&E tank is much more sensible.
However the system is still venting some water, at least when the pump turns off. The noise still happens. I have tested this by turning the heating & hot water off and waiting in the loft a couple of minutes for the pump to turn off. I have put a bottle under the vent pipe to check exactly how much. The first time it was only maybe 1 - 3 fl. oz but I've left it there and will check how much is there tonight.
So I don't think this is meant to be happening... The system is installed in the correct order, boiler -> vent -> cold feed within 150mm -> pump -> 3 way valve. I don't think there's any bypass, but I see the boiler instructions say this is generally not needed.
Pump is a grundfos 15-50 and he left it on setting 3 when he left the first time. I have experimented with changing it down to 2 and its my impression that it seems to be less coming out, but I don't know if that is affecting it or not.
Should I worry about this? I believe this is generally bad for the system as it (probably fairly slowly at this rate) oxygenates the water? Any idea what the cause is?
Thanks
Matt
