Unvented Cylinder - Tundish Leak

[AOIS]

Would anyone be able to advise the likely cause of the tundish overflowing on my unvented cylinder please?

 

[Best]

Overflowing? As in, - water coming out of the tundish onto the floor?

 

[Best]

Firstly, if your unvented unit is discharging water, then it needs serviced by an unvented qualified plumber.
The tundishs can often let some water out onto floor. If they are letting a lot of water out, then the discharge pipe might be too small, or blocked, or pipe end down into a blocked gulley.

 

[AOIS]

It was a small puddle of water just under the tundish.

 

[ShaunCorbs]

Best to get it checked out by a unvented qualified person (G3 registered)

 

[AOIS]

Last year the same thing happened and they installed a bigger tundish. It’s now occurred again.

 

[AOIS]

It’s also leaking down the pipe and l there is a wet patch on the ceiling below.

 

[ShaunCorbs]

Last year the same thing happened and they installed a bigger tundish. It’s now occurred again.

Any chance of a pic of what they've done ?

 

[AOIS]

This was replaced.

 

[Harvest Fields]

The tundish isn’t really the issue. Get an unvented Engineer out to check it all over and give it a service.

 

[Best]

There shouldn’t be any water going into tundish, so you have a fault with your unvented cylinder, or it’s controls or pipework.
You might also have something wrong with the discharge pipe, but get your unvented unit serviced - has to be done once a year.
Edit, - Harvest beat me to it.

 

[Harvest Fields]

There shouldn’t be any water going into tundish, so you have a fault with your unvented cylinder, or it’s controls or pipework.
You might also have something wrong with the discharge pipe, but get your unvented unit serviced - has to be done once a year.
Edit, - Harvest beat me to it.

Makes a change

 

[AOIS]

Thanks for the advice all. It was serviced in November.

 

[ShaunCorbs]

Thanks for the advice all. It was serviced in November.

How long was he there ?

 

[Harvest Fields]

Thanks for the advice all. It was serviced in November.

Get the engineer back to have a look at it for you. Sometimes things like this happen.

 

[Best]

Thanks for the advice all. It was serviced in November.

Something wrong with it and perhaps previous fault wasn't resolved

 

[Best]

How long was he there ?

Tempted!

 

[AOIS]

Could this issue be related to a intimitant knocking noise from my boiler?

 

[Harvest Fields]

Maybe. Get an engineer out, but make sure you tell them that it is an unvented cylinder as not all can work on them.

 

[Welder]

Your statement about them changing the tundish screams at me they have ZERO idea.

Unf many engineers think they are competent to work on UVCs. However, without doing the courses they simply cannot know enough and certainly not understand them intimately enough to fault find.

Ask to see your engineers G3 ticket. If they cannot provide move on to someone who can. Sorry, but safety & pragmatism must take precedence over £.

There are a number of potential causes. Some far more serious than others. It really does need looking at properly and by a G3 qualified person with at least 18mths under their belt. Hell, every a school day for me...

Good luck and pls let us know how you fair.

 

[AOIS]

Your statement about them changing the tundish screams at me they have ZERO idea.

Unf many engineers think they are competent to work on UVCs. However, without doing the courses they simply cannot know enough and certainly not understand them intimately enough to fault find.

Ask to see your engineers G3 ticket. If they cannot provide move on to someone who can. Sorry, but safety & pragmatism must take precedence over £.

There are a number of potential causes. Some far more serious than others. It really does need looking at properly and by a G3 qualified person with at least 18mths under their belt. Hell, every a school day for me...

Good luck and pls let us know how you fair.

Thanks you

 

[Welder]

Just realised. In the image you posted is the pipe into the top of the tundish the same size as the one out of the bottom? 15mm? If so that further reinforces my earlier assertion of whoever did it not being G3 qualified and not knowing the UVCs.

It is a core requirement for the lower pipe to be at least one size up from the one going into the top. So, if 15mm into top then 22mm out of bottom. If 22mm into top then 28mm our from bottom.

This size mismatch MAY be a cause of the overflowing out of the dish, BUT more importantly, it should not be running in the first place so needs some form of remedial action.

 

[AOIS]

For the 3rd time in 18 months I have a small leak appearing on the ceiling under my unvented cylinder.

Last time this happened was in March and I was told this was as a result of the air gap needing replenishing which the plumber did for me at the time. It was previously done in November last year during the systems first service.

It is normal for the air gap to need replenishing every 4 or 5 months please?

 

[AMGasServices]

Does it have an external expansion vessel or is it built in the tank ?

What pressure was it topped up to last time ?

 

[AOIS]

It is all built into the tank. It’s a Megaflo indirect cylinder.

 

[Harvest Fields]

It is all built into the tank. It’s a Megaflo indirect cylinder.

There is one on my estate that needs doing every 6 months.

 

[AOIS]

Why do some need this others don’t?

 

[AMGasServices]

Air may be escaping from somewhere.

 

[Best]

For the 3rd time in 18 months I have a small leak appearing on the ceiling under my unvented cylinder.

Last time this happened was in March and I was told this was as a result of the air gap needing replenishing which the plumber did for me at the time. It was previously done in November last year during the systems first service.

It is normal for the air gap to need replenishing every 4 or 5 months please?

If you are having to keep topping up the air gap, you could get your G3 qualified plumber to install an external suitable expansion vessel

 

[Harvest Fields]

If you are having to keep topping up the air gap, you could get your G3 qualified plumber to install an external suitable expansion vessel

I suggested that to the bloke around the corner to me but he wasn’t having it

 

[Best]

I suggested that to the bloke around the corner to me but he wasn’t having it

Some people just won’t listen.
Should then have told him, - all he can do is pay for install of a brand new replacement Megaflo.