Noisy Vented Y Plan.

[andy_s]

I have an open vented y plan central heating system, the pump is located in the first floor airing cupboard. Boiler is a concord WRS 240A in the ground floor kitchen. Initial problem, the hot water was not as hot as it usually was. I traced the fault to a reduced flow out of the indirect heating coil, the pipe was very nearly blocked and very magnetic. The feed from header tank was tee’d into the outlet of the coil! I have replaced the section of blocked pipe and re-routed the 15mm cold water feed into the 22mm vent, which is about 150mm from the inlet of the pump.

The system has always been noisy when on water only, I guess the air passing through has contributed to the original pipe blocking up. Having replaced the pipe I’d like to address the cause of the noisy hot water circuit. I can bleed all the air out with the pump running and the gas off so that the system is quiet and cool, but about 10 minutes after the boiler fires up I get the familiar swoosh through the pump in the airing cupboard. I have system cleaner circulating at the moment and would like to get a result before I flush out and re-fill with the inhibitor. The vent rises up above the FE tank before bending back down and I haven’t seen any sign of pumping over. All ideas gratefully received. Thanks in anticipation, Andy.

 

[ManchesterGas]

Why have you combined the feed/vent. Does the boiler allow it? Do you know what happens if you move the feed / vent around the system?

Is the boiler kettling ?

 

[Mike Jackson]

Probably dragging air in. I very much doubt that a combined feed and vent configuration is allowed on a concord as it probably doesn't have an overheat stat.

 

[stevetheplumber]

fit a myson air seperater to the cold feed and vent is the best way out

 

[andy_s]

Thanks for the advice given. The boiler does have a return temperature stat, i moved the feed as most y plan info indicates that the feed and vent are on the inlet side of the pump and a max of 150mm apart. The boiler isn't kettling either. I did consider an air seperator but i'm very restricted for space even though the aerjec isn't that big. The vent pipe goes up over the FE tank and then back down, ideally what height difference must there be between the surface of the water in the tank and the end of the vent? Thanks again, Andy

 

[WHPES]

Air separator is a bodge

Convert to sealed system, get rid of that silly little tank in the loft and all sorted - it's the way to go!

 

[diamondgas]

I have an open vented y plan central heating system, the pump is located in the first floor airing cupboard. Boiler is a concord WRS 240A in the ground floor kitchen. Initial problem, the hot water was not as hot as it usually was. I traced the fault to a reduced flow out of the indirect heating coil, the pipe was very nearly blocked and very magnetic. The feed from header tank was tee’d into the outlet of the coil! I have replaced the section of blocked pipe and re-routed the 15mm cold water feed into the 22mm vent, which is about 150mm from the inlet of the pump.

The system has always been noisy when on water only, I guess the air passing through has contributed to the original pipe blocking up. Having replaced the pipe I’d like to address the cause of the noisy hot water circuit. I can bleed all the air out with the pump running and the gas off so that the system is quiet and cool, but about 10 minutes after the boiler fires up I get the familiar swoosh through the pump in the airing cupboard. I have system cleaner circulating at the moment and would like to get a result before I flush out and re-fill with the inhibitor. The vent rises up above the FE tank before bending back down and I haven’t seen any sign of pumping over. All ideas gratefully received. Thanks in anticipation, Andy.

Surging is the opposite of pumping over andy_s ... open vent gets sucked on, basically! Ends up blocking up the pipe where the return is connected too!

The boiler you're referring too is dodgy to combine f&e though! Maybe worth considering replacing TBH and eliminating any crud build up?

 

[stevetheplumber]

Air separator is a bodge

Convert to sealed system, get rid of that silly little tank in the loft and all sorted - it's the way to go!

i dont think you can seal a wrs as there is only one stat i dont even remember a kit for these even if there was its probably out of production

 

[andy_s]

Once again, thanks for all the input guys. Due to available budget i think my most affordable solution at the moment is to try and fit an air seperator in prior to the pump (sorry WHPES!) i have seen a model that includes a 15 mm cold feed pipe, i am assuming that this will return my vent to a 'dry' state rather than the 'wet' vent i have created and will be acceptable for my very old but reliable cast iron lump. Then i guess it's time to start saving.......:sad3: