Tundish on unvented cylinder

[Mgrant]

Hey is it usual for a tun-dish to splash alot of water out when testing the discharge of the pressure or temperature relief on full? There's no problem with the discharge pipe over 300mm before first bend after tun-dish and less than 9 meters in 22mm.

 

[townfanjon]

yep James they generally do splash, some a lot, some a little.

 

[AWheating]

yes it always happens and they are not really a very good design/fit for purpose

 

[Meady]

I always find this happens, my one at home only goes about 5 metres in 22mm and is 500mm from the tundish to the first bend. You have to let the pressure go slowly or the water goes everywhere.

 

[AWheating]

I always find this happens, my one at home only goes about 5 metres in 22mm and is 500mm from the tundish to the first bend. You have to let the pressure go slowly or the water goes everywhere.

What a plumber who bothers to check/service his own plumbing?? what is this world coming to???

 

[Mgrant]

Ok if the pressure or temperature relief did blow of is it likely to be at full bore or not? The splashing could cause some damage especially with the position of the cylinder in the loft.

 

[SimonG]

Ok if the pressure or temperature relief did blow of is it likely to be at full bore or not? The splashing could cause some damage especially with the position of the cylinder in the loft.

It will be running quicker in a failure mode than just a simple manual discharge.

 

[Mgrant]

So if the cylinder did discharge it would cause quite abit of damage due to the tun dish splashing. Would it be worth getting the manufacturers out to look at it?

 

[josh]

As said nearly all of them do it, so what would they say?
500mm of 28mm straight from tundish does take it away quick enough though but still get the odd drip sneak out.

 

[Mgrant]

As said nearly all of them do it, so what would they say?
500mm of 28mm straight from tundish does take it away quick enough though but still get the odd drip sneak out.
It a 22mm connection on the tundish outlet. And 22mm pipe takes it away 0.7 meters to first bend under tundish and less than 9 meters of 22mm pipe. Its splashing out of the tundish not backing up.

 

[Mgrant]

Its alot more than an odd drip that's sneaking out

 

[josh]

I wouldn't worry about it, i'm sure someone on here has but i'v never heard or seen a PRV/expansion relief let go full bore. only ever trickle.
You can go on and worry forever about everything and anything if you wanted.

 

[Mgrant]

I wouldn't worry about it, i'm sure someone on here has but i'v never heard or seen a PRV/expansion relief let go full bore. only ever trickle.
You can go on and worry forever about everything and anything if you wanted.

Thanks so they don't usually discharge on full bore? Its only on full bore when it is splashing over.

 

[townfanjon]

The only thing I try do to help is to try make the first bend as far away from the tundish as poss, defo use a pulled bend , and try keep the rest of D2 on a 'fall'.
If it's just about horizontal and you use an elbow, it won't help.

 

[josh]

I'm sure some have but i have never heard of it/come across it.
You have followed the regs and MI's so what more can you do.