dnb

OK, I know I'm not Dunc, but I have used a combi boiler before - the boiler instructions said there was no need for a bypass radiator (father in law and I installed the heating pipework, and we got a Corgi to do the boiler gas,flue, system check & commisioning)

The boiler didn't do anything wrong in the two years I lived in the flat with it

Surely if you turn the heating off, then there's no boiler heat to dissipate - even when making hot water?

Of course, if you're running the heating then it's not a good idea to turn all the rads off... (it said that in the book as well)

Of course this may not be the case for your boiler.

An explaination from the expert would be in order now.

Damn my spelling!!

[Edited by dnb - 8/6/2002 12:02:00 AM]

[Edited by dnb - 8/6/2002 12:04:36 AM]

[Edited by dnb - 8/6/2002 12:10:13 AM]

dnb

Ah I see - the dreaded thermostatic rad valves - we used a separate electrical room thermostat, and had normal valves on the rads, so they could never be completely shut off (unless you were indulging in particularly inventive daftness...)

That explains that one

BTW are there any thermostatic rad valves that actually work? All the ones I've seen don't!! (new house is full of them, and they are going to be replaced)

[Edited by dnb - 8/6/2002 9:09:04 PM]

Big Col

Hello

Need advice on my taps. Some background first. I live in a ground floor flat. The hot and cold water tanks are in a cupboard in the bathroom. The taps in the bathroom work OK. However in the kitchen the pressure from the hot tap is very poor. You can turn the tap almost 4 full turns before the flow starts and then it is only a trickle. The cold tap has good pressure (the same as in the bathroom) but again you can turn the tap 2 full turn with no effect then another half turn gives you full flow, there is no intermediate position.

Is the problem the taps in the kitchen? BTW the taps are one of those mixer type.

Any advice much appreciated as I'm not much use at home DIY.

Colin

Luke

Colin

Lets start at the shallow end!! Has they always been like this??

If yes- Check to see if there are any "Ball o fix" valves fitted. These could be turned right down. It a straight compression valve that can be adjusted with a flat head screwdriver.

If No- Maybe the internals on the taps have gone....

Good luck

Big Col

Yes it has always been like this. Only been in the flat about 9 months.

Luke

This is the valve that I am talking about!! There also could be gate valves.. Big red handles. The phot shows it in its closed position. Turn it inline for full flow.
Next check to see if the plumbing is inline... Also there are no valves in the airing cupboard.

Be lucky

scooby nutter

Is it a new flat??

These new kitchen taps have small (8-12mm)pipes going to them and it doesnt take a lot to block a pipe!

had it before myself where a piece of Cylinder lagging(foam stuff)had fallen into cylinder and gone all the way to the kitchen sink hot tap!!!!
It was my own fault for not turning the cylinder upside down!!Probably some clown at the Cylinder manufacturer!!

Also check to see if the nozzel of the tap unscrews(is it mixer tap??)check water flow again.
check under sink for valves,its very unusuall to find gate valves under the sink ,usually ballofix valves,when screw slot is inline with pipe, the water is on.

Check cylinder cuboard for a gate valve,its on the pipe from the big tank to the bottom of cylinder,check its open.

Failing all this disconnect tap under sink and then switch hot water on and see what the flow is like.

Plumbing

Duncan....Plumber and Corgi reg.Gas installer

mj

dunc, oh wise one of all things connected to water/heating'

why does a combi boiler need a bypass rad?

it's not a trip up question, it's just im having an ongoing row with her indoors to leave a radiator on to dissipate heat from the boiler- is this correct, and if so what happens if you dont leave a rad open? does this **** the boiler?

stevem2k

I had the same symptoms ... are the other hot taps ok ?

Turned out to be nothing more than a washer in the hot tap that had turned to mush.

Steve

scooby nutter

dnb,mj

Bypass rad,

There may come a point when the boiler is on and all radiators are upto temp(by means of Thermostats on rads)these will shut the valve causing no flow of water.Now if all these rad valves shut the pump on the boiler isnt clever enough to sense this and still keeps on pumping water round,but the water doesnt go anywhere and so the boiler will overheat.
We usually leave a radiator with just normal valves on.Mostly its the bathroom rad as its useful heat.
You could also have a loop of pipe under the floor before any rads are tapped off(think you need about 3 or 4 meters)so if all the rads do switch off then the pump can still pump the water around this small loop of pipe and not overheat.

Also ,even when running hot water and if the heating is switched off the pump will still run on after.Think when you boil a kettle,when it boils and switches off the water doesnt stop at that temp it continues to rise for a few more degrees(latent heat??).Its the same with the boiler.If you run hot water for a long period,eg bath,then when you switch the tap off the pump is still running to get rid of the heat.My Worcestor cdi does this for about 1-2 minutes after,because the boiler is near the bathroom ,the bathroom rad sometimes gets a little luke warm.


Hope that helps

Duncan

scooby nutter

dnb

The thermostats we use mostly are West therm valves.Never had a stuck one yet and quite cheap.Honeywell are also very good but sometimes the pins stick during summer ,so valve doesnt work.

The thermos should be put on the flow pipe on the rad,it will work best on the flow.Sometimes if they are put on the return pipe they can make a banging noise.

Duncan

Amen Corner

Colin,

Maybe this isn't right, but I thought it was a requirement that the kitchen tap was direct mains supply? In which case it wouldn't be coming off your cold water tank at all. That would suggest that it was the kitchen tap that was knackered rather than anything else.

But like I say, that could just be bollux.

dnb

Thanks.

Looking forward to getting the new heating & hot water now. The house can be put ack together then, and I can start to play with the Suabru again.

Big Col

Cheers for the replies folks.

Going on the advice here I think its the taps that are gubbed. Can you change the internals of a tap or do you have to replace the whole lot?

BTW here's a pic. This trickle of water is the hot tap open full.




Colin

scooby nutter

Amen corner

yes you are talking bullox

LOL

Its the Hot tap he is having problems with

Big Col,

I think you should switch the hot water off in the cylinder cuboard(or where ever it switches off) open the kitchen hot tap to make sure water has stopped running.remove plastic head of tap.using a suitable good fitting spanner and holding the actual tap remove the tap guts.Have a look down the hole where the guts of the tap sits/and where the washer seats and check that its clear.
Now get your missus/mate to watch the hole where the water comes out and now you open the gate valve in cylinder cuboard.

See what the water flow is like (you may need a upturned cup/dish just incase the water pressure is high cos it might hit the ceiling)!!

Give it a go...

Also what is on top of your Water tank??Sometimes loft insualtion falls in and gets sucked down the pipe and it causes blockages.I have had this loads of times.

Keep us informed BUT:::i cannot be held responsible if you flood the place!!!!!!

Duncan

Amen Corner

scooby nutter:

scooby nutter

Amen:
Quote:: The taps in the bathroom work OK. However in the kitchen the pressure from the hot tap is very poor. You can turn the tap almost 4 full turns before the flow starts and then it is only a trickle.

LOL

BIG Col,
Switch hot/cold water off ,Remove tap inserts and take them to bits.Grease with silicone based grease(not as in silicone from a tube),re-assemble and jobs doneprobably just binding inside as they are metal to metal insides.

Duncan