Are you allowed to run a discharge pipe from a cylinder into a soil pipe?

[uwantsome]

as above, cheers

 

[Meady]

I'm pretty sure you are as the company I work for does it on site, but we run high temperature pipe to it straight from the soil and have a hepVo trap (one of the dry traps) connected to the tundish.

 

[plumber0808]

A unvented cylinder yes.

 

[uwantsome]

yes thats what i thought. Ive been running them in on site for ages now. Straight out of the unvented cylinder using a hepvo valve, into inch and a quarter push fit and then connected to a soil pipe. An old guy at my firm says you are not allowed to do this though, he's adamant of it

 

[plumber0808]

It is permitted. Stick it to him

 

[AWheating]

yes but you should only be doing it if there is no possible route to outside. As mentioned it needs to run throught a hepvo valve as detailed in its instructions and i think in the building regs.
You did need to ask LBC permission to route to waste but i think thats changed now. You also need to be able to prove the waste system can take the high temps from such systems.

 

[uwantsome]

well its site work so there is always a route to outside with copper. Most of the houses i do now are 3 story and the cylinders are on the top floor and that would mean taking a copper pipe through each floor and core drilling a hole, thats fine but when the soil pipe is about 4 metres away its easier and at less cost to connect it into a soil pipe. Also a neater job, i just hope what i have been doing is right

 

[AWheating]

ask your local building control or the nhbc inspector. Normally cost should not be a factor in the way the discharge is run tbh.

the waste pipework needs to be of a material (normally pushfit) type capable of a working temp of above 100 degrees i think, have a read of part g.

if its on the drawings as youve fitted it then your covered and i would not worry.

 

[uwantsome]

cheers, yeah it is push fit and the nhbc guy has passed every single house I've done and the site wins awards. obviously the old guy is talking rubbish.

thanks for the replies

 

[plumber0808]

I wouldn't point it out to the NHBC inspector as they are now done. Just incase he did decide to make you change them based on it can go outside. If your 3 floors up with a soil stack 4 meters away its going in there every time.
would save a lot of money on materials and labour.

 

[garyplumb]

I've seen a soil pipe collapsed after heating water had been discharged into it, so it's not ideal to go to the stack but can be done.

 

[Dan Masey]

This is from a megaflow and runs strait into the soil stack next door.

 

[aqualogic7]

is there a tundish higher up forming a AA airgap

 

[stratplus]

That hepvo should be vertical for unvented discharge as in g3 regs.

 

[Dan Masey]

 

[Dan Masey]

That hepvo should be vertical for unvented discharge as in g3 regs.

Really?

 

[Howsie]

Yep. And the D2 doesn't comply either.

 

[stratplus]

Yes, it can go horizontal in other applications but when used for a discharge should be vertical. I'll dig out my G3 book to be sure.

 

[stratplus]

From the Bpec manual: Hepvo "must be vertical and adjacent to the water unit"
The pipe should be polypropylene to BS5254 or BSEN1451.

 

[stratplus]

That tundish contravenes regs as well. They've come out of the tundish straight to an elbow.

 

[Dan Masey]

Yep. And the D2 doesn't comply either.

Why not mate? The middle pic isn't D2 by the way. It's a condense from the boiler above. Pic 3 shows D2 with a constant fall. I didn't instal this by the way. I just came across it today. Like to learn these things. Not questioning anyone.

 

[Dan Masey]

Ah you mean the 300mm before the first elbow??

 

[stratplus]

Tundish is fitted right next to the double socket! These can splash if they discharge!!

 

[Howsie]

I'm surprised the BI's dog didn't spot this 😉

 

[Dan Masey]

Learning all the time. There are 65 of these fitted in a building we look after. ( we don't do the heating / cylinders by the way). They all get serviced every year. Wouldn't these changes need to be made on a service then? Maybe the regs were different when installed years ago.