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G

Gromit

Hello all

I am currently having a system boiler and unvented indirect cylinder fitted. The access to the outside for the discharge pipe is difficult and involves lifting chipboard floors so the engineer wants to connect it to a soil stack (I think it's called) - the big pipe that the toilet is connected to. Is this ok?

Many thanks and advice is much appreciated.
 
From a safety point of view, lift the boards and have the discharge outside where it is visible. It would need to be almost impossible to run the discharge outside to justify doing it any other way.
Having the discharge in a visible location may be the only way you know a very important safety device showing you something is wrong.
 
GrahamM said:
From a safety point of view, lift the boards and have the discharge outside where it is visible. It would need to be almost impossible to run the discharge outside to justify doing it any other way.
Having the discharge in a visible location may be the only way you know a very important safety device showing you something is wrong.
Click to expand...

i dont really agree with what you are saying, properly connected to the soil stack with the right connection is acceptable as per MI so why would it be unsafe, having near boiling water outside isnt inherently safe, and if it does discharge down into the stack due to temp/pressure relief valve opening i'm sure you will hear it all over the house
 
As far as I am aware kirkgas the MI's for most cylinders and my own training state to comply with building reg. G3:
"ensure the discharge from any safety device is conveyed to where it is visible"

Ideally but not the only option is discharging between 70-100mm from ground into a drain.

Only if there is no other reasonable option alternative arrangements may be carried out for the discharge termination. In my opinion lifting a few boards would not be classed as a reason not to comply with the above.
 
Hi. There are a few issues. The continuos fall required will be compromised with a trap, which will dry out providing the unit is behaving its self. The temp of discharge from temp relief valve (could be super heated steam)is hot enough to deform soil pipe if upvc. Unless changes to regs have taken place discharge pipe must be metal. The Mi. may not address uk buildig regs but European?
 
GrahamM said:
As far as I am aware kirkgas the MI's for most cylinders and my own training state to comply with building reg. G3:
"ensure the discharge from any safety device is conveyed to where it is visible"

Ideally but not the only option is discharging between 70-100mm from ground into a drain.

Only if there is no other reasonable option alternative arrangements may be carried out for the discharge termination. In my opinion lifting a few boards would not be classed as a reason not to comply with the above.
Click to expand...

this is where i have an issue with how we all get trained and updated, you are right depending on when you were trained, i am right as i am using the current version of the training material, when you get re-assessed after the 5 yr period you will be given the version i have now and will see that you could have been using the HEP2O fitting to safely discharge to a soil stack, i'm not having a go as you are using what you were given, but you arent keeping yourself up to date with legislative changes, and depending on where you work someone isnt doing their duty by updating you (if you are an employee the firm has this job, if you are SE it is your job) the new unvented training/assessment material is a couple of months old now, so in theory you could be 4.5yrs away from getting the update, its the same with gas, how do you get updated? also you mention the MI you have, this will have been printed based on old info, download the new version of your cylinder to see if it mentions the new way to fit the D2 pipe
 
I like to think I keep upto date with current changes in procedure/regs as much as I can and it was only 4 months ago I done my unvented.
Why does it state in the latest Building Regulations Part G (April 2010) paragraph G3(3)(b)
"ensure that any discharge from safety devices is safely conveyed to where it is visible but will not cause a danger to persons in or about the building"?

This is the MI for the cylinder installations from the Heatrae Sadia and Ariston website they do not mention anything about terminating into a soil stack as far as I can see and appear to state following the regulation quoted above.
http://www.heatraesadia.com/docs/Megaflo_systemfit_-_Issue_5_-_36005882.pdf

http://www.ariston.co.uk/uploads/doc4ac4ac5b7dc27.pdf

If i am wrong I do not mind being told so and would just like to sort this out. Are the building regs and my recent teachings wrong ?
 
Thank you all. In the event the joists went the right way and they have put the discharge externally without too much trouble. My brother in law works for the NHBC and one of his top guys didn't know the up to date rule about discharge pipes into stacks so it is clearly a complex subject.
 
Not if it is in back of a cupboard. Are you going to have the tenant check the tundish on a regular basis on the off chance it may be passing?
That is why I was told the preferred option is to have the termination at ground level outside if possible. More chance of being noticed. Does not appear to be the case for others.
 
There is a self build estate near us and I am told on good authority ( although I have never seen it) That on one house the tundish was at the back of a cupboard and the only way building control would pass it was if it had a camera with a monitor in a visable place ? A lot of trouble I would have thought but you never Know
 
The preferred method will always be to outside but building methods and practices sometimes make this impractical.
Say in a multi storey building there may be over 100 flats. Now you could have 100 discharge pipes of various sizes, all labeled with the house number for easy identification or as would normally be the case there would be a few central discharge pipes feeding from many properties.
Either way it would not be easy to identify where the discharge was coming from and more than one could be discharging at the same time.

Things had to evolve to suit building practices and the HepVo filled that purpose.
High temperature plastics have always been available so when the correct materials are used there is no problem.

GrahamM

G3 3.56 states
The discharge pipe (D2) should be made of:
a. metal; or
b. other material that has been demonstrated to be capable of safely withstanding temperatures of the water discharged and is clearly and permanently marked to identify the product and performance standard (eg as specified in the relevant part of BS 7291) ie polypropylene

The tundish should be fitted in a visible position.

Bit of history lesson for anyone who may be interested.

When the regulations were first written sometime in 1987 (but were not due to be on the statute until late 1988) it was still standard practice in the uk for hot water to be storage fed. At the time no one really envisaged a time when all water in new build and most replacements would be potable. Combis, although they had been available since the 70's were rarely seen.
I did my unvented over the weekend of 16th to 18th October 1987 (i remember it as it was the weekend of the great storm when Sevenoaks became one oak). Before there was any unvented fitted anywhere in Britain. I left the course thinking this is the way to go.
I built a house in early 88 and fitted an unvented (3 bar polystel, state of the art?? looked like a big butane bottle) and had to delay moving in until July as the water board would not give me a supply because it did not comply with water regulations! I had to apply to the Secretary of State for Scotland for a class relaxation which, much to the annoyance of the water officer was given.
How things changed in such a short time and my small claim to fame, 1st domestic unvented cylinder fitted legit in Scotland:D
 
GrahamM has a point. If no-one knows that the regs have changed or altered and even the Cylinder MI does not include the fact that you can now dishcharge into a soil stack. Something is massively wrong with our training/systems etc etc.
Must admit I didn't know that you can now discharge UV into a soil stack with HEP2o stuff. Now I know why I must have lost a job a couple of weeks ago. You live and learn!
 
There's no point in having a tundish if it isn't sited where it can be seen. The point is so that the discharge is apparent. Having said that, I've been to customers with BG contracts and the BG engineers haven't bothered to check the discharge pipe outside when a loss of system pressure has been reported.
 
Message to tamz.
Do you have a blue plaque on the outside of you house to signify you're acheivement. If not why not?

Must admit this has been a good thread,
 
The manu's all know but choose not to update their instructions for whatever reasons. Have a read through various manus instructions and you will find they all spout the same stuff with the same wee drawings.......Laziness? You should know the regs as it is your job to know them.
As for the training places, you have to question the quality of the training and what the "trainers" are actually aware of.
For anyone going through training who is not made aware of this is a disgrace but the rules ARE stated in the regs so they have a way out, but i admit they may be hard to interpret sometimes.

Buryboy
You owe me a pint for the lesson but i'll let you off :D
 
Message to tamz

Hope you meant a pint of beer not Good quality scotch.

Thanks agin.
 
Buryboy

No. The cylinder lasted 5 years before i came back from holiday to a flooded house! It was a polythene lined steel cylinder (it really did look like a big butane bottle with an expansion vessel on top) and it was ****ing out the 8" flange on the top.
Just off a delayed flight from Tenerife and in to a sodden hall (luckily a bungalow). Wife moaning her t... off as if it's my fault so i had to get the tools out and work until 4 in the morning fitting a Highflow400 which i had in the yard for a job the next week.
Cylinder went in the skip as it was worthless being made of steel.
 
but if you discharge into a soil stack then isn"t there a risk of health+safety, all them little germans running up with there mates mr.bacteria,?

sorry just a thought,
 
cjg said:
but if you discharge into a soil stack then isn"t there a risk of health+safety, all them little germans running up with there mates mr.bacteria,?

sorry just a thought,
Click to expand...

The bacteria will fit right in. Its a drain. Not all bacteria are bad btw.
 
This is what I love about this community. The wealth of knowledge available and the balanced opinions and not forgetting criticisms:D is priceless. It gives us the help and knowledge to become more educated, and hopefully better Engineers/Plumbers/Tradesmen/People.;)
Cheers everyone
Graham
 
ocentric said:
I've been to customers with BG contracts and the BG engineers haven't bothered to check the discharge pipe outside when a loss of system pressure has been reported.
Click to expand...
.

What can i say:) Tradesmen at their best :D
 
ocentric said:
There's no point in having a tundish if it isn't sited where it can be seen. The point is so that the discharge is apparent. Having said that, I've been to customers with BG contracts and the BG engineers haven't bothered to check the discharge pipe outside when a loss of system pressure has been reported.
Click to expand...

i agree that the tundish should be sited where discharge will be seen, however the main point of the tundish is to provide an airgap to prevent backflow. what would happen if someone didn't observe the g3 regs and the bend on the discharge was too close to the valve causing discharge to slow up to the point the tank still exploded...............the tundish provides egress for expanding 100 plus degree steam in emergency situations in which a baddly fitted pipe causes a hinderance.

KJ
 
Want to use the HEPvo but need to know if possible.

I have already solvent welded a boss adapter to stack. Can this be used or how do i get it out to change to rubber one? Already plastered and boxed in so limited space.

Also need to connect small basin and washing machine into the same pipe. I know the instruction said you need separate pipe just in case of blockage, I could run another pipe along the wall and tee in right next to boss adapter.
Is that possible?

Info: (new build, 150ltr or 180ltr tank)
Total pipe run from util area to stack is only 2m, hot tank next to washing machine then wc to stack. (no drain out side to discharge to)

If cant do above will have to go back to original plan and use Gledhill Pulsacoil (allot more money)
 
If you are running the discharge pipe in plastic it must be done in high temp plastics (polypropylene) and cannot have anything else using the same pipe.
You will need to put another strap on boss onto the stack to take the basin and washing machine.
 
you can only follow the MIs that the cyl comes with and if they are not updated how can you do something different, if there was an insurance issue later on I bet I know who would be the patsey and it will all fall down hill onto the installer.
 
GrahamM said:
As far as I am aware kirkgas the MI's for most cylinders and my own training state to comply with building reg. G3:
"ensure the discharge from any safety device is conveyed to where it is visible"

Ideally but not the only option is discharging between 70-100mm from ground into a drain.

Only if there is no other reasonable option alternative arrangements may be carried out for the discharge termination. In my opinion lifting a few boards would not be classed as a reason not to comply with the above.
Click to expand...

bpec training notes say EITHER the tundish or the termination point MUST be visible
 
buryboy said:
GrahamM has a point. If no-one knows that the regs have changed or altered and even the Cylinder MI does not include the fact that you can now dishcharge into a soil stack. Something is massively wrong with our training/systems etc etc.
Must admit I didn't know that you can now discharge UV into a soil stack with HEP2o stuff. Now I know why I must have lost a job a couple of weeks ago. You live and learn!
Click to expand...

with all due respect to all those who are damn busy doing a fine job day in day out, but it is the duty of the responsible person for the company to ensure all working practices meet current standards, whether that is a massive construction company or self employed, the info is out there, it is the same with gas regs that change, it amazes me the number of guys coming in for re-assessment who dont know about FSD's for appliances in multi occupancy dwellings, and that has been out for yrs, the latest edition of unvented training has all this info in it, ok you trained 4yrs ago and are not due to come back till next yr but you may be working to the old standards and costing yourself time and money or actually losing a job by not knowing you can now do something sa different way, ie terminate unvented via the hep2o
 
before i got to page 2 i was saying to myself soil pipe not a problem tundish in a visible position will show discharge.
 
it is definitely perfectly acceptable to vent into the soil stack, new build townhouse apartments do it all the time!!
but you MUST incorporate a VISABLE/AUDABLE WARNING to indicate all is not well... this can take the form of an external vent pipe chucking water down the wall, or in your case, a correct-for-purpose tun dish built into the discharge pipework to provide this warning.
WRAS regs.
 
kirkgas said:
it amazes me the number of guys coming in for re-assessment who dont know about FSD's for appliances in multi occupancy dwellings
Click to expand...

What is a multi occupancy dwelling? Is that one of these student hives places:):D
 
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