Tundish

[mickyg]

if your discharging a UV to waste pipe there is specific guidelines. It MUST go into a hepvo trap, theres no alternative. The price for the adaptor includes the trap as well.
http://www.nhbc.co.uk/NHBCPublicati...ical/StandardsExtra/filedownload,34921,en.pdf

The discharge is classed as part of the installation and "technically" should only be installed by a competent person.
If you block the discharge you make it dangerous, if you block the hot water draw off nothing comes out the tap. thats the difference. Not that I'm suggesting your going to block it, just trying to explain the difference.

 

[GaytonTonner]

Do as was done before, simply use 32mm plastic right up to the discharge on the boiler, no need for tundish, just needs an air gap which will be created by the 32,, pipe

Is that legal? What if the pressure relief is dripping, you would not know.

 

[mickyg]

Do as was done before, simply use 32mm plastic right up to the discharge on the boiler, no need for tundish, just needs an air gap which will be created by the 32,, pipe

Is that legal? What if the pressure relief is dripping, you would not know.

you would cos your boiler would keep losing pressure and stop working. I always leave a visible gap so any drip is visible, but its not essential. Manufacturers overal in all cases.

 

[silverback18]

Do as was done before, simply use 32mm plastic right up to the discharge on the boiler, no need for tundish, just needs an air gap which will be created by the 32,, pipe

Is that legal? What if the pressure relief is dripping, you would not know.

The boiler would cut out at 0.7bar, there is no law that says you need a tundish at the boiler, with the Atag you have to remember that you have the condense coming out of the same pipe.

 

[GaytonTonner]

Do as was done before, simply use 32mm plastic right up to the discharge on the boiler, no need for tundish, just needs an air gap which will be created by the 32,, pipe

Is that legal? What if the pressure relief is dripping, you would not know.

The boiler would cut out at 0.7bar, there is no law that says you need a tundish at the boiler, with the Atag you have to remember that you have the condense coming out of the same pipe.

Thank you. I downloaded the instructions, which does not say fit a tundish. It says something like an "open connection". It appears you are right if their instructions are correct. That is much simpler then. There is the problem of a normal trap drying out while away, while a HepVo trap will not.

 

[GaytonTonner]

Expanding on the topic although not related to the topic problem. Other boilers have the discharge pipe into copper. I see no reason why this cannot be run into a tundish and high temperature trap and waste pipe. This is no different to what atag are doing and their boilers are legal. Doing this will tidy up the walls of blocks of flats and stop the dripping.

Yes other boilers have copper for the safety discharge only, this is combined safety discharge and condense, because of the condense plastic pipe has to be used, consense will corrode copper

The atag appears unique in having the condensate and pressure discharge combined into one plastic pipe. This is a great touch and much easier to install as well. If a HepVo trap can be fitted to the pressure discharge of an atag then I see no reason why it can't be fitted to any boiler. The temperature of the discharge from an atag is the same as say a Glow Worm, yet the likes of Glow Worm say the discharge must be to outside and in copper. It doesn't make sense. If heat resistant plastic is OK for an atag then it is OK for any boiler. The atag way is much easier and there are no ugly pipes, which drip a lot, on the outside walls.

 

[Biggles..]

You could fit a hepvo to any boiler or unvented cylinder,part g has recently been amended to show this.

However like the atag you have to follow a simple set of guidelines,hepvo trap,high temp plastic pipe etc.

 

[silverback18]

Expanding on the topic although not related to the topic problem. Other boilers have the discharge pipe into copper. I see no reason why this cannot be run into a tundish and high temperature trap and waste pipe. This is no different to what atag are doing and their boilers are legal. Doing this will tidy up the walls of blocks of flats and stop the dripping.

Yes other boilers have copper for the safety discharge only, this is combined safety discharge and condense, because of the condense plastic pipe has to be used, consense will corrode copper

The atag appears unique in having the condensate and pressure discharge combined into one plastic pipe. This is a great touch and much easier to install as well. If a HepVo trap can be fitted to the pressure discharge of an atag then I see no reason why it can't be fitted to any boiler. The temperature of the discharge from an atag is the same as say a Glow Worm, yet the likes of Glow Worm say the discharge must be to outside and in copper. It doesn't make sense. If heat resistant plastic is OK for an atag then it is OK for any boiler. The atag way is much easier and there are no ugly pipes, which drip a lot, on the outside walls.

You only require a trap if you are entering a soil pipe, if you are discharging over a trapped gulley you do not need a trap as the boiler has its own trap.

As you say Polypropylene pipe and fittings which is what you need for high temperatures are availiable from Screwfix, wickes etc, but you need to support a pipe used for this purpose every 300mm

 

[GaytonTonner]

The BES http://www.bes.co.uk polyprop waste pipe is pushfit. Is their solvent weld suitable?

 

[GaytonTonner]

You could fit a hepvo to any boiler or unvented cylinder,part g has recently been amended to show this.

However like the atag you have to follow a simple set of guidelines,hepvo trap,high temp plastic pipe etc.

I never knew that. So there is no reason to have external copper pipes that drip

 

[silverback18]

The BES http://www.bes.co.uk polyprop waste pipe is pushfit. Is their solvent weld suitable?

Polypropylene is only availiable as push fit, solvent waste is not suitable for high temperature.

 

[GaytonTonner]

The BES http://www.bes.co.uk polyprop waste pipe is pushfit. Is their solvent weld suitable?

Polypropylene is only availiable as push fit, solvent waste is not suitable for high temperature.

Is all push-fit polyprop? Many makers or sellers do not specify and many sellers don't know.