I have a two year old Vaillant ecoTEC Plus 615 system boiler which runs the heating and charges a Megaflow hot water cylinder.
I've noticed a rushing noise (like theres debris in the water) from it when its heating the cylinder. It kicks in when the flow temperature reaches approx 75c -80c and will then continue through to and during during pump overrun. When the flow diverts to rads after heating the hot water, theres what sounds like a lot of air whooshing through the rads for a few minutes then it is and remains nice and quite. Strangely, when I bleed the rads there is little if any air.
I can't say how long its been doing this because the boiler is in the airing cupboard and I don't usually go in the cupboard when the boiler is heating the hot water. I have been monitoring this for a few months now and it seems to be getting worse.
Things to note -
The pump speed is set to speed 1 for rads and overrun, and 2 for hot water.
The boiler is the highest point in the system and I have opened the AAV fitted to the pump.
Theres also an AAV fitted to the loop that feeds the hot water cylinder which is open.
Boiler is set to and holding a pressure of 1.5 bar.
Can anyone help me? Thanks.
I've noticed a rushing noise (like theres debris in the water) from it when its heating the cylinder. It kicks in when the flow temperature reaches approx 75c -80c and will then continue through to and during during pump overrun. When the flow diverts to rads after heating the hot water, theres what sounds like a lot of air whooshing through the rads for a few minutes then it is and remains nice and quite. Strangely, when I bleed the rads there is little if any air.
I can't say how long its been doing this because the boiler is in the airing cupboard and I don't usually go in the cupboard when the boiler is heating the hot water. I have been monitoring this for a few months now and it seems to be getting worse.
Things to note -
The pump speed is set to speed 1 for rads and overrun, and 2 for hot water.
The boiler is the highest point in the system and I have opened the AAV fitted to the pump.
Theres also an AAV fitted to the loop that feeds the hot water cylinder which is open.
Boiler is set to and holding a pressure of 1.5 bar.
Can anyone help me? Thanks.