Anyone know things bout boilers?

[Bearsy]

I've got this combi boiler thing and sometimes after i have a shower or whatever it makes like horrible banging noises and then packs in. I've noticed that if i run the cold tap while it's making the bad noises they goes away though.

Anyone know what causes this? Do I need plumber or can i fix it myself?

[norwaysaint]

Well don't ask Junction 9. He knows **** all about this sort of thing.

[CB Saint]

I thought you had got rid of her

[Colinjb]

Low water pressure I guess. Just a wild guess.

[Bearsy]

Well don't ask Junction 9. He knows **** all about this sort of thing.
That smells like an in joke. Did he flood your kitchen?

I've just thought - it might be relevant - there was a problem with my toilet in that it was always running and cos it was the one adjoining my bedroom the noise was annoyings and one night when i was drunk i turned off the cold water at the mains thing under the sink. Didn't occur to me at the time there was a valve on the actual toilet pipe. Guy who come to fix my toilet said i was "idiot".

Could this have caused air-lock type scenarios?

[Bearsy]

Low water pressure I guess. Just a wild guess.

How do I make high water pressures?

[Colinjb]

Could this have caused air-lock type scenarios?

Possible, you may need to bleed some radiators, really make 'em bleed.

[Weston Super Saint]

I guess low water pressure too.

There should be a pressure gauge with a red line on it - between 1 and 2 bar - take a look and see what the reading is.

If it's low, there should be a small tap on the filling pipe, turn it to open until the pressure reaches the red line and it should be fixed....

[Colinjb]

How do I make high water pressures?

Most combi boilers have an 'infeed' tap. Before you locate that though check to see if there is a pressure guage on the boiler itself (maybe behind a panel) if it is less then 1 Bar then yes, low pressure. Add water until it's above at least 1 bar. (Do NOT exceed 2.5 bar)

[Bearsy]

Most combi boilers have an 'infeed' tap. Before you locate that though check to see if there is a pressure guage on the boiler itself (maybe behind a panel) if it is less then 1 Bar then yes, low pressure. Add water until it's above at least 1 bar. (Do NOT exceed 2.5 bar)

I've opened the panel thing but there's not a guage thing, there is a little LED light for "Low Systems Pressures" but it isn't on so I'm thinking dats cool!

[Colinjb]

I've opened the panel thing but there's not a guage thing, there is a little LED light for "Low Systems Pressures" but it isn't on so I'm thinking dats cool!

Then you may well have a serious case of air in the system. Is the heating on? If not turn it on, let the radiators heat up and check if any are less warm at the top then at the bottom. If there are any that have some 'cooler' areas at the top, then that's an air bubble.

You will need a radiator bleeding key to drain the air off. Most radiators will have a square shaped valve on a top corner.

[Bearsy]

Thanks for suggestions Colin! I've checked and radiators are all good. It never happens with the central heating anyways only when i run the hot taps or shower. I was thinking they were on separate systems or something?

Maybe I'll call the plumber back. I'd of done it sooner but i didn't want him calling me "idiot" again!

[Colinjb]

Thanks for suggestions Colin! I've checked and radiators are all good. It never happens with the central heating anyways only when i run the hot taps or shower. I was thinking they were on separate systems or something?

Maybe I'll call the plumber back. I'd of done it sooner but i didn't want him calling me "idiot" again!

No problem.

A combi Boiler heats both the shower/taps and the radiator 'circuit' but you are right, they are seperate systems. It could be some trapped air in the bathroom/kitchen tap pipes that is causing this 'banging' when the pressures and air in the pipes shift around. At least you know the central heating is all good.

And if he calls you an idiot, wrap a kipper round his face.

[RedArmy]

Then you may well have a serious case of air in the system. Is the heating on? If not turn it on, let the radiators heat up and check if any are less warm at the top then at the bottom. If there are any that have some 'cooler' areas at the top, then that's an air bubble.

You will need a radiator bleeding key to drain the air off. Most radiators will have a square shaped valve on a top corner.Correct me if I'm wrong, but that wouldn't make much difference if the air is in the hot water system.

You would usually know if there is air in the HW system because the taps would normally sputter. Sounds like it could be scaled up.

[Colinjb]

Correct me if I'm wrong, but that wouldn't make much difference if the air is in the hot water system.

You would usually know if there is air in the HW system because the taps would normally sputter. Sounds like it could be scaled up.

No, that's a fair point, something blocking the water flow would make sense. Either way we've ruled out any issue with the central heating side of things. Bearsy, keep us posted.

[saintscottofthenortham]

Air in pipes.

God damn. I'm wrong. I'll stick to wire and scalextric.

[Bearsy]

Correct me if I'm wrong, but that wouldn't make much difference if the air is in the hot water system.

You would usually know if there is air in the HW system because the taps would normally sputter. Sounds like it could be scaled up.

The taps ain't usually spluttering but i've found that if when the boilers is making the Bad Noises i turn on the hot tap then the noises stops and after a few seconds a spurt of superhot air and waters comes out hissing like a startled cat.

[Dog]

You have a hungry rat that loves warm copper.

[SO16_Saint]

i have absolutely no idea what the matter is with your water, but I have to say that you, Bearsy, is one funny bear

[jawillwill]

Has anyone put Junction 9's name forward yet? He's good at this sort of stuff apparently. Just make sure your bedroom door is locked when he comes round though.

[Saint-scooby]

Have you had a de scale anytime in the last few years?

[scotty]

Have you had a de scale anytime in the last few years?

Yes, but it was only minor.




(C what I did there?)

[Block 18]

If you have had a water meter fitted recently, you will need to have a shock arrester fitted the the cold inlet of the combi to prevent the banging sound in the shower.
http://www.rwc.co.uk/public/training/april02.pdf
The reason being your incomming mains pressue is now different on is prone to fluctuation, this will affect a shower more than other taps as they react theromstaticly.
Its a simple job and should cost no more than £70 to £80 parts and labour

[Bearsy]

That's interesting Block 18s but i ain't sure! It don't ever happen when the shower or taps is running, it only happens like 30 seconds after I've shut them off. You get angry noises and then the pipes start banging about, unless i immediately start running a hot tap which lets out a burst of steams or run a cold tap (not sure why that helps - does running cold tap put more cold water in your boilers?).

Also, it never happened before I had the issue with my toilet, but happens all the time since so i'm thinking i must of hurt it's feelings when i turned off the waters at the mains thing under the sinks. I think I'll call plumber. I was gonna try descaling last night as suggested by Scooby but couldn't figure out where I'm sposed to stick the fizzy tablet things.