Hot water and Central Heating off, Radiator still on!

[Softus]

respectfully softus, if i don't assume the boiler's firing up the how else is water getting hot?

I'd say that you're using the word "assume" when the correct word is "deduce".

Fault-finding, in any field, goes like this:

1. Expect.
2. Observe.
3. Theorise.
4. Test the theory.

In other words...

1. Determine how the system should behave.
2. See how it actually behaves.
3. Work out what could account for any mismatch.
4. Do something in order to check that you're correct.

You seem to have skipped step 2, but then you can get help with that here. However, you've rushed to step 3, skimped it a bit, and then omitted step 4 entirely.

But never mind all that. The real question is why something that didn't use to happen is now happening. The first thing to determine is why the one radiator differs from all the others. Once you find that out, the rest should be easy.

For example, with the system idle, and the rogue radiator valves open, do any of the pipes around the pump and zone valves get warm to the touch?

 

[diverdee]

when this problem occurs with the radaitor are the pipes to the water tank hot also.if so could be wired wrong and hot water on constant and boiler firing at night if tank cools a little bit

 

[JamesUK]

But never mind all that.

quite.


i'll investigate the question you raised. many thanks.

 

[JamesUK]

ta diverdeee.

will investigate.

 

[JamesUK]

as an additional problem/sympton my wife and i have just agreed that the hot water coming out of the taps is generally considerbaly cooler than before this problem manifested itself.

shed any light?

i'm 'deducing' ( ) that much of the heat is going into the problem radiator.

 

[diverdee]

is poss!! need to find out what else is working at same time then maybe able to narrow problem good luck

 

[JamesUK]

hmm. just noticed the valves are labelled ch and hw.

right now; hw is on, ch is off.

pipe area around hw is valve is warm, pipe area around ch is very hot.

significant?

 

[JamesUK]

hmm. and on closer inspection, the hw valve seems to be damaged. the little black 'lever' bit, excuse the amateur description, seems to have been snapped off.

 

[Softus]

hmm. just noticed the valves are labelled ch and hw.

right now; hw is on, ch is off.

pipe area around hw is valve is warm, pipe area around ch is very hot.

significant?

If you could refine the word "area" it would help - is the pipework hot on the 'downstream' side of the CH valve, i.e. its outlet?

If so, and if you've deselected CH at the programmer, then the valve is open when it should be closed.

If a valve is open when it shouldn't be, you need to check that it's not jammed. If the powerhead is removable then you can wiggle the spindle to see. This can also free it, but if it's jammed once then it will happen again. The jamming can be caused either within the wet part of the valve, or by the gear train of the powerhead.

If HW is also deselected at the programmer, then the boiler is lighting when it should not be. If the CH valve is fully open then it could be the cause.

Also, if the boiler is lighting then the pump should be running - have you felt the pump?

 

[JamesUK]

thanks a lot for that softus.

ok, seems both sides of the valve are hot. so yeah, it would seem that the valve is open. i've spotted the little 'lever' that is meant to move and this does seem to function properly when the ch is turned on/off.

it is the case that the boiler is lighting when it shouldn't be.

stupid question; where's the pump? what am i looking for? is it in the pics?

 

[JamesUK]

would also like to add that the boiler has trouble maintaining optimum pressure according to the gauge.

 

[gasgeezer]

Pump is in the boiler

 

[Softus]

If the system is losing pressure, then you must need to top it up.

If you top it up then you'll be using fresh water.

If you use fresh water, then you'll be diluting the concentration of corrosion inhibitor in the system.

If you do this for long enough, corrosion will start.

If corrosion progresses for long enough, then Magnetite and rust will start to block pipes, valves and heat exchangers, and cause to wear to the pump.

If this corrosion becomes advanced, then you will lose heating efficiency, and risk leaks from corroded radiators.

The pump is within the boiler casing.

 

[diverdee]

sounds like heating valve passing water through when it shoudnt.it may or may not be firing the boiler.it could be that when water is switched on it is also doing the rads.switch everything off allow to go cold.then switch each one on seperatley and see if both exit pipes on the valves get hot.this will tell you for defo if a valve is passing.dont forget thou that the one rad could be plumbed on the hot water circuit not on the heating this is not unusual on a old system

 

[JamesUK]

it's looking like two faulty valves do you think?