overflow on combi boiler

across

please can someone tell me if the overflow to my combi boiler should be constantly dripping it is a little brass fitting outside if this makes sense and it is wet on the floor all the time which means i have an icy floor. i have asked the people who did it but they said it drips to stop the temp guage going into the red, many thanks for any advise!

ariba10

If the drip is from the end of a pipe from the boiler to the outside, it is probably the from the pressure relief valve. Is the presssure gage showing too high a pressure. It is usualy about one bar

across

yep sorry i didnt mean temp guage it is the pressure valve youre right !!!
anyway yep it is always high and just at end of "(green) about to start 3(red)!!!!!!!!! but when i had the engineer back he said dont worry it needs to drip to keep pressure right but it is so messy the kids keep standing under it like it's a shower(even though it only drips!)cos they like getting wet can i do anything to stop it or put something on to catch it?

bestyman

Hi,
From your post it would seem the dripping pipe is from the pressure relief valve but are you sure that its not the condesate pipe?

If you have a condensing boiler this will also have a pipe ( probably 3/4 inch and plastic) that discharges condensation from the flue. This pipe should discharge into a gulley etc where it will not be a nuisance.

ASSUMING ITS THE PIPE FROM SAFETY VALVE (usually 15mm copper)
A combi boiler pressure should be between 1 and 1.5 bar when cold. As the water heats up it expands so the pressure will rise but under no circumstances should it go above 3 bar ,

If it does go above 3 bar when hot there are a few possibilities.

1. It was above 1.5 when cold.
2. The filling loop is passing water ( it should be disconnected)
3. There are too many radiators on the system for the size of the boiler ( well infact the size of the boilers expansion vessel)
4. Faulty expansion vessel.

DO NOT STOP END OR BLOCK THE DRIPPING PIPE!! Should the pressure in the boiler rise above 3 bar ( for above reasons) a safety valve is fitted that discharges water outside, basicly to stop the high pressure blowing the boiler up.

If the valve drips when pressure below 3 bar this would suggest a faulty pressure relief vale ( safety valve)

In any event it is not supposed to drip so have this fixed as soon as possible.

across

thanks i think i'm i'm going to get onto them again because it has always dripped no matter what and ive had it now since september if anyone has anymore advise it is really appreciated thank you so much for helping!

economiser

If it is the pressure relief (safety) valve outlet it should not be dripping. Probably got a bit of grit stuck in the valve. Opening it for a second or two and then closing may flush it out. You may then have to top up the pressure again from the water supply.

across

finally got the boiler fixed!! there was actually a leak inside too!as well as the puddle outside!! two different problems outside was cos they had never turned the stop taps off on the two pipes originally in september when it was installed!! the leak inside was the condensation bottle lid had cracked it had been put on too tight originally!!so needed a new one! the man from worcester boilers was so rude he wasnt going to touch it cos i had a worktop that he disliked he managed to do the job but said they will put a marker by my address to never come back again unless the worktop is removed!! anyway cant understand how the inspector passed it then!!
i rang and told them never to send that engineer around to my house ever again!!
many thanks too all of you who replied earlier to this problem!! :T