Megaflo Tundish

[SimonG]

We had this one before. G3 is for above 15 litres. 15 and under you don't need G3 but you do need to follow the instructions around pressure relief, check valve, expansion and first draw off points.

 

[BLOD]

Since 2010 G3 is for all hot water storage - vented & unvented.

 

[SimonG]

Not applicable for 15 litre and under, should be, but isn't.

 

[BLOD]

Maybe I've misunderstood it, but the link below clearly states G3 now covers all hot water storage vented & unvented.

Amendments to Part G of the Building Regulations

 

[SimonG]

I stand corrected, section 3.19 of document G3 " Water heaters with a capacity of 15 litres or less that have appropriate safety devices for temperature and pressure will generally satisfy the requirements set out in G3(3)."

Good call Blod.

 

[dontknowitall]

Bloomin red tape ...

 

[mickie]

its all over this site..

 

[SimonG]

Bloomin red tape ...

It's not so much the red tap as the ambiguity of the statement in the G3 regs they have a set of regs upto 500 litres but then make special mention of under 15 litres. So why don't the 15 litre and under come under the upto 500 litres.

 

[PlumbBobBob]

they couldn't be bothered to rewrite all of the regulations and just changed the parts that had changed.

 

[mickie]

15 litres burting isnt going to bring a house down

 

[SimonG]

Sounds like a challenge for the Mythbusters!

 

[mickie]

YouTube - ‪MythBusters - Exploding Water Heater‬‏

cant find a small 15litre one being blown up

 

[GrahamM]

15 litres burting isnt going to bring a house down

It might not bring the house down, but if installed incorrectly it still has the potential to become a pressure cooker and burn your skin off if it was breached suddenly.
At 3bar pressure the boiling point is approx. 150°C. If that is suddenly vented to atmosphere it will instantly turn to steam.

 

[leakeee]

if water is even getting to the tundish it means you got problems. not might be a big one but an issue that should be looked at.