Drip from pipe into pipe under combi boiler.

Hi, I live in a block of flats and I recently got the Bulex/Valient same company, serviced.
My question is, there is a drip from a pipe into another pipe which has been cut to receive this water, but I have never noticed a drip before. Is it OK or should I get the service man out again? Thanks.

 

It's an indication of a fault.
Give him a call and tell him that you can see water dripping into the tundish from the PRV.

 

Thank you!

 

Welcome.

 

It has stopped dripping! Shall I wait to see if it happens again?

 

You need to be more specific about the exact appliance you have.

However, regardless of this, the photo you uploaded shows a pressure relief valve (PRV) and a tundish (open pipe) connected to a discharge pipe (ribbed pipe in the photo).

This setup is designed to handle the "uncontrolled" expansion of hot water within a sealed system under fault conditions.
Normal expansion is handled via an EV (expansion vessel) and this should cope with pressure increases thus preventing any "let-by" at the PRV, into the tundish.

Next time there is a demand for heat (either Central Heating or hot water) check the tundish again for let-by. Also check any pressure gauge you have for pressure readings above 3bar.

I would call the engineer and inform him of what you have witnessed.

 

Thank you for spending time, early Saturday morning! It was dripping after a F1 fault which happens time to time and I reset it by the reset button. I just had a hot shower and it is not dripping.
Will be going away for a week now and a month in August, can/will/should unplug from the scoket before I go? Again thank you, for being wlling to help others.
FYI

 

I'd still let the engineer know about the drip and the F1 fault. Your EV needs checking for air side pressure (should have been done during the service).

But, for now, if you're going away then yes, power it off and it also would be good practice to turn your incoming cold stop cock off. You should have one in your flat... Under the sink or in the boiler cupboard perhaps.

 

as an addendum .... the engineer may also have tested the PRV when the appliance was being serviced.

It is sometimes asked for by manufacturers that as part of the service procedures the relief valve is tested but an experience engineer will know that an older valve can sometime not seal again properly and can let by if it has been lifted. If the engineer did do this test then he needs to know the valve is now passing

 

UPDATE. Good Morning! Without a flashing red light or F1 there was a drip which I saw this morning. I used the hot water and it seems to have stopped. We dont use much hot water, boiling a kettle for dishes and DH shaving, face washing in the am/pm, would NOT using the hot water enough cause the drip. Also is this problem able to be left for 2 weeks and safe to unplug and leave incoming cold water stop cock on as that is in the basemant of the building and not sure where it is.

 

It is possible the hot pipes, when you use the boiler, are drying the water that is weeping/ leaking

Suggest you call the engineer. Also do not use the boiler so that area that is leaking will be wet for the engineer to see and then repair

 

Don't worry "too" much about the stop cock for when you go away... Its just a "good thing" to do if you are away from home... Especially if you live in a communal block and have occupied premises below you.

By turning off the power to the boiler, there is no chance of any water being heated and therefore "expanding" and thus forcing the PRV to lift and let by.

Might be worthwhile getting your own stop cock installed where the mains enters your flat... Or as close to that point as is possible.

 

By turning off the power to the boiler, there is no chance of any water being heated and therefore "expanding" and thus forcing the PRV to lift and let by.

So it is a good idea to unplug it? Can you say yes or no. I have not had a reply from the engineer and as stated before will be travelling.

 

Yes! It will do no harm to power the boiler off.

Different scenario if it was the middle of winter and there was a chance of cold water freezing in your pipes.

From what you have described thus far, it suggests that the leak (via the PRV) is due to expansion of heated water... Removing the heating of this water (by switching boiler off/unplugging it) should prevent the pressure increase and stop the leak.

"however" you may have other issues, such as a filling loop which is permanently connected and letting by... Thus increasing system pressure (even when cold) and powering the appliance off would not prevent this! So, disconnect and cap the filling loop also.

Ultimately, for peace of mind, whilst you are away from home, you need to either isolate both main water and power Or get your engineer back in.