Temperature pressure relief valve dripping

ThisIsWeird

Lulu58 said:

ThisIsWeird said:

It isn't by any means vital, just 'recommended'.

That all sounds do-able.  I'll see if I can get some quotes.

When I checked the cylinder etc this morning there was more water on the plinth, but I still couldn't feel or see any signs of a leak.

I was out this morning but when I got home I could feel it was cold in the house so I checked the garage. The boiler had switched itself off again and there was a lot more 'wet' water (rather than the plinth being damp) on the plinth and floor.

Various parts of the piping etc were wet so I dried everything off and waited. After a while I could see a steady drip coming out of another valve (pressurised?) which is alongside the motorised valve for the water, see photo. It has 10 bar 775C Caleffi on the top of it. A quick internet search suggests it may be a Caleffi Robocal Automatic Air Vent with Check Valve but I'm not certain.

I'm not sure if it's the source of the latest leak or not. The drip seems to be coming out of the 'bobble' on the top.

I tried turning on the boiler and nothing happened so I turned the heating up which seemed to kick start various bits on the cylinder. I waited a few minutes and tried the boiler again and it started up this time. The display was showing the two T's on their side as before alternating with the figure 29 was has increased to 62 and the T's have gone.

There was definitely a motor type sound from the boiler as if something was trying to start up several times before whatever it was actually worked it reminded me of the sound of a fan.

I'm wondering if I need to get Worcester Bosch out once I get the cylinder sorted as it's under guarantee.

That is, indeed, an auto air vent. They shouldn't leak water out that top bit, only air. You can try tightening down that top knurled cap - just fingertight, and it should stop the leak.

Not sure I'd try turning the potential boiler cupboard into a drying room, as that could bring associated issues. Fitting an extractor would defeat the object of insulating against heat loss, and not fitting one would have cond forming on any cold bits like the cold mains supply pipes. The cupboard would, tho', lend itself to a dry storage place in the garage - anything that you don't want to be affected by damp.

Anyhoo, tighten that top knurl, and see if the water stops. 

Lulu58

ThisIsWeird said:

Lulu58 said:

Various parts of the piping etc were wet so I dried everything off and waited. After a while I could see a steady drip coming out of another valve (pressurised?) which is alongside the motorised valve for the water, see photo. It has 10 bar 775C Caleffi on the top of it. A quick internet search suggests it may be a Caleffi Robocal Automatic Air Vent with Check Valve but I'm not certain.

That is, indeed, an auto air vent. They shouldn't leak water out that top bit, only air. You can try tightening down that top knurled cap - just fingertight, and it should stop the leak.

Not sure I'd try turning the potential boiler cupboard into a drying room, as that could bring associated issues. Fitting an extractor would defeat the object of insulating against heat loss, and not fitting one would have cond forming on any cold bits like the cold mains supply pipes. The cupboard would, tho', lend itself to a dry storage place in the garage - anything that you don't want to be affected by damp.

Anyhoo, tighten that top knurl, and see if the water stops. 

Thanks again, ThisIsWeird.
The plumber has tightened everything, including the top knurled cap. This morning there are no signs of any leaks on the plinth or floor ... result!
I'm going to phone WB today to see if I can get someone out to look at the boiler.
You've raised some good points regarding the drying cupboard, thank you.

ThisIsWeird

Not sure there is anything actually wrong with the boiler. I think it's normal for it to start up on demand, and then go through a process which could take some time; pump on first (whirrrr), then it detects flow and return temps and checks that everything is ok, then fires up the burner. 

The two flashing 'T's mean something - I recall seeing it on mil's boiler, and I had to look it up. Something like it's running, but not firing the burner, or has shut the burner down for a while (whilst still pumping) to displace some of the hot water - something perfectly normal. I think.

I'd ask them about what you are observing first, before asking them to come out - who want a call-out charge only to be told rtbm, eh?

STOP PRESS. It might mean something else - the condensate trap needs refilling. Happens every time power is cut to the boiler. Do you have the manual for it? I'm surfin'.

ThisIsWeird

Page 6: https://www.worcester-bosch.co.uk/professional/support/literature/greenstar-cdi-classic-system-operating-instructions

This should only happen when the power has been fully turned off to the boiler - either via the front on/off button being pressed, or the power cut via the isolator switch.

It shouldn't happen when the boiler is turned 'on' and 'off' by the programmer or 'stat as it is normally.

So, unless you have been FULLY turning the power off to the boiler one way or another, there is something amiss. 

It takes quite a while for it to go through this process, as the boiler assumes that the condensate trap may need filling as the boiler was fully turned off (as it would for servicing, or the house being left empty, that sort of thing).

So, the process itself is normal, but it shouldn't be happening under normal use.

Either the power has been fully turned off, or your boiler has been wired incorrectly, or your boiler has a wee fault. Have you turned your boiler off via the front switch?

Lulu58

ThisIsWeird said:

Page 6: https://www.worcester-bosch.co.uk/professional/support/literature/greenstar-cdi-classic-system-operating-instructions

This should only happen when the power has been fully turned off to the boiler - either via the front on/off button being pressed, or the power cut via the isolator switch.

It shouldn't happen when the boiler is turned 'on' and 'off' by the programmer or 'stat as it is normally.

So, unless you have been FULLY turning the power off to the boiler one way or another, there is something amiss. 

It takes quite a while for it to go through this process, as the boiler assumes that the condensate trap may need filling as the boiler was fully turned off (as it would for servicing, or the house being left empty, that sort of thing).

So, the process itself is normal, but it shouldn't be happening under normal use.

Either the power has been fully turned off, or your boiler has been wired incorrectly, or your boiler has a wee fault. Have you turned your boiler off via the front switch?

Hi ThisIsWeird and thanks for this and your other post with the links to the boiler manual.
This whole issue started with the boiler basically dying - no lights, nothing. Just prior to this I heard a motor/fan type noise which sounded like something in the boiler trying to fire up 8 or 9 times then the boiler just died. It was the middle of the day and not particularly cold.
I turned the heating right up so the system was calling for heat. The cylinder/plumbing started doing it's thing but the boiler did not fire up.
I tried turning the boiler on a couple of times but it would not come on. I left it for a while and tried turning it on again and this time it fired up. I got the two T's on their side alternately flashing with a figure. There was no error code.
The second time the boiler died, I wasn't in the garage so I've no idea what happened. As before, all the lights were out and it wouldn't start. It was the middle of the day and cold but not freezing.
I turned the heating right up again, nothing. I left it for around 30 minutes and tried to start it again and this time it fired up with the flashing T's etc.
I explained to WB what happened. They are coming out next week.

Unfortunately, my excitement at having no leaks was a bit previous! We still have a small leak, possibly from the cold feed near the bottom of the cylinder.

At some point in the near future we're probably going to replace the three motorised valves as we've had problems with them, and also fit isolating valves to each one. The plumber will take a look at the leak above at the same time.
Not sure whether to replace the Caleffi circlip multibloc valve at the same time. There's no drip through the tundish anymore.

ThisIsWeird

That boiler has a permanent blue indicator light on it to show when it's 'on', doesn't it?  Ie, the light is always on, even if the boiler isn't running, and is just on standby?
When it goes 'dead', does that light also go off?
If so, there's surely an electrical fault, possibly just a loose wire, possibly a faulty PCB. This isn't being caused by an external component such as the valves.
Yes, you need a GasSafe out!

Lulu58

ThisIsWeird said:

That boiler has a permanent blue indicator light on it to show when it's 'on', doesn't it?  Ie, the light is always on, even if the boiler isn't running, and is just on standby?
When it goes 'dead', does that light also go off?
If so, there's surely an electrical fault, possibly just a loose wire, possibly a faulty PCB. This isn't being caused by an external component such as the valves.
Yes, you need a GasSafe out!

Hi, yes the boiler does have a permanent blue indictor light indictor to show when it's 'on'. The light went out both times when the boiler died.
I'm hoping the WB engineer can find a fault and sort it out, as opposed to saying there's nothing wrong with it and then we still don't know why it died twice.
Just for clarity, is there absolutely no connection between the boiler and the cylinder and associated plumbing etc which could result in the boiler dying? So even if the cylinder etc developed a fault, the effect would not be that the boiler would die?

ThisIsWeird

Lulu58 said:

ThisIsWeird said:

That boiler has a permanent blue indicator light on it to show when it's 'on', doesn't it?  Ie, the light is always on, even if the boiler isn't running, and is just on standby?
When it goes 'dead', does that light also go off?
If so, there's surely an electrical fault, possibly just a loose wire, possibly a faulty PCB. This isn't being caused by an external component such as the valves.
Yes, you need a GasSafe out!

Hi, yes the boiler does have a permanent blue indictor light indictor to show when it's 'on'. The light went out both times when the boiler died.
I'm hoping the WB engineer can find a fault and sort it out, as opposed to saying there's nothing wrong with it and then we still don't know why it died twice.
Just for clarity, is there absolutely no connection between the boiler and the cylinder and associated plumbing etc which could result in the boiler dying? So even if the cylinder etc developed a fault, the effect would not be that the boiler would die?

Almost certainly, there is no connection.

The blue light isn't 'controlled' in any way - it doesn't indicate anything (afaIk) other than the boiler is receiving power - it is ready for action. If that light goes out, something has interrupted the boiler's power supply. So, the fact the blue light goes out is significant.

That will be a loose wire or connection in the power supply to the boiler, or something electrical internal to the boiler - a dodgy connection, a dry joint, a loose wire.

Can you see the cable going to the boiler? Give it a wobble...

Can you ID the isolating switch on the wall nearby? Does it have a red neon light on it? If so, the next time the blue goes out, see if the red does too.

Lulu58

ThisIsWeird said:

Lulu58 said:

Hi, yes the boiler does have a permanent blue indictor light indictor to show when it's 'on'. The light went out both times when the boiler died.
I'm hoping the WB engineer can find a fault and sort it out, as opposed to saying there's nothing wrong with it and then we still don't know why it died twice.
Just for clarity, is there absolutely no connection between the boiler and the cylinder and associated plumbing etc which could result in the boiler dying? So even if the cylinder etc developed a fault, the effect would not be that the boiler would die?

Almost certainly, there is no connection.

The blue light isn't 'controlled' in any way - it doesn't indicate anything (afaIk) other than the boiler is receiving power - it is ready for action. If that light goes out, something has interrupted the boiler's power supply. So, the fact the blue light goes out is significant.

That will be a loose wire or connection in the power supply to the boiler, or something electrical internal to the boiler - a dodgy connection, a dry joint, a loose wire.

Can you see the cable going to the boiler? Give it a wobble...

Can you ID the isolating switch on the wall nearby? Does it have a red neon light on it? If so, the next time the blue goes out, see if the red does too.

Thanks as always, ThisIsWeird. 
I'll check the cable today. I think I know which one is the isolating switch but none of our switches have a neon red light. I'll check to make sure which one is the switch for the boiler.
Hopefully the WB engineer can get to the bottom of it today. In a way it would be good if the engineer found a fault so that at least the problem is identified rather than finding nothing if that makes sense.

ThisIsWeird

Yes - intermittent faults like this are the worst!
It should be very helpful to him that you noticed the blue light goes out, too, at these times of fault. And, since the 'condensate trap is being refilled' symbol (the two Ts) comes on afterwards for the typical 15 minutes, that, too, indicates that the boiler has completely lost its power supply each time.
But whether it's an internal or external cause, that's his task to find!
If he can't find the cause, then they'll often replace the front control panel or PCB. Remind me - is it under warranty?
To confirm, there is no way the rest of your CH system - valves, stats, progs, etc - can be causing this power loss that I can think off. Not unless it's been wired completely wrong, but then it would demonstrate this fault every time the external device activated! Infinitesimally unlikely.
The external controls & devices - prog, stats, valves, etc - act to tell the boiler when to 'fire up', but the boiler already needs to have been 'on' - with that blue light lit.