Worcester Bosch Combi boiler - non return valve - help needed

[mainvein]

Hi,

Hoping someone on here can help me clarify the water regs on my problem:

Had a worcester bosch combi boiler installed in Nov last year, had no probs until last night, replaced a radiator, then re-pressurised the boiler back to just over 1 bar, then after about 3 hours, it made a very funny noise and lost all pressure, it wouldnt then refill and started leaking from the boiler. A guy from worcester Bosch came out and fixed it.

But the first thing he said was that 'the non return valve has been fitted onto the cold water feed, it should be on the central heating feed' - you want to get the installer out and swap it over (this is on the filling loop), saying thats not right at all

phoned the installer and he said categorically that the non return valve goes on the cold water feed and that the guy from worcester bosch doesnt know what he is on about.

can anyone shed some light as to which way round this should be? As one of these two professionals hasnt been trained properly. where can i find these regulations too?

If anyone could help that would be amazing

thanks

steve and claire

 

[payney1974]

non return goes on the cold main side but i bet at least 80 % are on the c/heating side (the ones i see anyway)!! \If you think about it when the filling loop is disconnected you could connect the cold main side to a garden hose to do anything.

 

[Puddle]

Hate to agree with Mr Worcester man but he is right ,non return valve should be fitted on heating side
If it did not would save us a lot of problems as we could remove the filling loop and drain system from there but this is not the case
yes you could put hose on valve and water garden,as you could on any tap in the house
what we do not want is people fitting drinking water points to heating system,which could happen if non return valve not on heating side ,they find their mistake then fit to mains and turn on with pipe work full of rusty heating water,hay presto cross contamination
Or as used to happen so often before filling loops became available and washing machine valves were used,some one would come along and fit washing machine to heating side and end up with white shirts going in and rusty brown shirts coming out
And no hot water and heating afterwards as all system pressure gone to fill washing machine

 

[mainvein]

thanks for the quick repsonses. are there any official regs on this? just read the boiler manual (makes no sense) but does seem to indicate that it should be fitted on the CH feed.

the installer said that the water regs changed last year? and that i can find them online to prove he is right. cannot find anything as yet.

 

[LIFES A GAS]

I think the regs changed a few years ago, as said above most external filling loop non-return valves are fitted on the system side, the regs say the non return should be fitted to the mains CW, most now incorporate an isolation valve within the non-return valve fitting. One advantage is that you can use the filling loop valve as a system drain point which you can't if the non-return is on the system side. To satisfy water regs the flexi-hose must not be left connected after use, it is an offence to do so. Not sure how you stand with some of the built in types, Worcester have a key that when removed creates an air brake others like those fitted to many Combi models don’t.

Martin

 

[payney1974]

Puddle, i thought they used to be fitted on the CH side but im sure the regs changed a few years ago?

 

[Ockyvines]

The regs did change a few years back (2003?)
The non return valve should now be fitted on the water main.
It used to be the other way around

 

[oldplumber]

The regs did change a few years back (2003?)
The non return valve should now be fitted on the water main.
It used to be the other way around

just looked at the regs on line (Im a sad bu**er) and the 1999 regs still apply and were amended in 2003 to change wc system flush amounts but nothing else really. The central heating system is still fluid cat 3 hence double check valves required on them, and the cat 3 fluid must be downstream therefore that would mean as far away as possible from the cw supply, ie on the central heating side combined with a permanent air gap ie remove the braided hose. Nothing else in the regs to say otherwise. additionaly if you look at mfis on filling loops they indicate the check valve should bolt onto the heating side, me thinks puddle is right along with wb man

 

[stevetheplumber]

non return valve should be on the mains water end of the filling loop not sure when it changed but for ages i was dismantling loops to get them the way i still thought was right

 

[Puddle]

I know some years ago there was some talk about this, as generally the non return valve should and has always been on the supply side, however we went through ok,should be alright to leave filling loop connected, then no, required disconnecting ,then if you disconect,non return valves would be required to be fitted to all mains out lets in property ,as all could be then connected to heating side, and so on, thought the last was filling loop is the exception to rule, or if you wanted to cover yourself one should be fitted to each side, heating and mains supply
It is generally accepted in the industry that there is a bigger threat form cross contamination by having non return valve on mains side than the heating side of the removable loop

 

[oldplumber]

non return valve should be on the mains water end of the filling loop not sure when it changed but for ages i was dismantling loops to get them the way i still thought was right

wheres this laid down, nothing seen in regs when i checked today?

 

[payney1974]

Hi,

Hoping someone on here can help me clarify the water regs on my problem:

Had a worcester bosch combi boiler installed in Nov last year, had no probs until last night, replaced a radiator, then re-pressurised the boiler back to just over 1 bar, then after about 3 hours, it made a very funny noise and lost all pressure, it wouldnt then refill and started leaking from the boiler. A guy from worcester Bosch came out and fixed it.

But the first thing he said was that 'the non return valve has been fitted onto the cold water feed, it should be on the central heating feed' - you want to get the installer out and swap it over (this is on the filling loop), saying that's not right at all

phoned the installer and he said categorically that the non return valve goes on the cold water feed and that the guy from worcester bosch doesnt know what he is on about.

can anyone shed some light as to which way round this should be? As one of these two professionals hasnt been trained properly. where can i find these regulations too?

If anyone could help that would be amazing

thanks

steve and claire

Steve & Claire as you can see there is a 50/50 split on here as to which side it goes on but i wouldn't bother losing any sleep over it its not that important as long as you disconnect the braided hose after filling system. Worcester Bosch guy sounds like a bit of a jobs worth!

 

[LIFES A GAS]

All I can say is, I have fitted several new kits to existing systems where the old one had failed for one reason or another, the instructions supplied by the manufactures shows the non-return valve fitted to the mains water side, so I fitted it in accordance with manufactures instructions.
Martin.

 

[Ockyvines]

wheres this laid down, nothing seen in regs when i checked today?

I checked in the MI of the Baxi Solo HE that I fitted today and it states clearly that the non return valve should be fitted on the water main side

 

[oldplumber]

got to suck back here, reading wras regs today and states double check valve tobe on cw main, live and learn. reason being that if the check valve is on the primary heating cct and an expn vssl fails an over pressure situ can occur, damaging the check valve and if the temp connction pipe is on and the feed valve open contaminated water will escape into the water suply system, see regs R24.2