Sealed System Problem - Cold Xmas!

[Ste Kearney]

Of course it's Chrismas Eve and no plumbers around for love nor money...

Been out a lot (pantos etc!) last few days and this is the first time I've really noticed the lack of hot water and the house feeling colder so I suspected sth might be wrong!

First sign, patch of water in Son's bedroom. A few days ago he complained of being too hot so I turned the thermo valve down. This patch of water has only become noticeable now.

Second sign is zero bar on boiler gauge (Worcester 9.24). Obviously no hot water and no heat.

So removed the thermo part of the valve and reseated it, there is still a very slight leak and it's now turned up full like it was before. I've refilled the boiler with the filling loop thing pressure to 1.5 bar (red arm is set to 2.0 bar), and turned boiler on, hot water to on. That was over an hour ago and still no hot water and stone cold rads.

I seem then to have lost too much water in the heating system but without drain keys I'm stuffed. But why would I not get any hot water? Or, asuming the whole system has been off for 2/3 days with no pressure, will I have to wait longer for system to pressurise and heat up? Pressure seems to be holding with boiler on but I dunno why I get no hot water at all - used to be almost instant.

Help, kids are freezing!

Ste

[John Rumm]

First port of call, have a read through the FAQ:

First sign, patch of water in Son's bedroom. A few days ago he

Where is the water coming from?

That would do it....

With many boilers of this type the heating system needs to be filled and working for the hot water side to work correctly.

No - the system is pressurised with the filling loop. After it is full it should run. One thing to check however is that you don't have large amounts of air in the rads. Do you have a radiator bleeding key? (If not look at the bleeding valve at the top of the rad, some can be opened with a screwdriver). Bleed each rad to chck there is no air in there. If there is you may need to top up the pressure again afterwards (or even suring if there is lots of it).

Does the boiler have a display / indicators etc? Does it say anything? Does it have a "reset" button? If so, try pushing it. (it is likely that if the boiler was running while the system was loosing pressure, the boiler would have "tripped" as a safety measure. It may stay in this protective state until you clear it).

Some things to look out for. A thermostatic valve, on a radiator like you described, should not leak like that regardless of being open or closed. Hence you have a problem there that will need to be addressed at some point. See if you can see where the leak is coming from and report back here.

Also if you have drained and refilled too much water in your system then you may have lost some of your corrosian inhibitor. Adding more might be a good idea to prevent future problems.

[Ste Kearney]

Think I fixed it, but....

Hard to tell for sure but it seems to be the where the pin that the thermo valve setting knob turns or presses - not sure how it works.

No key no - will get one for sure!

I said boiler is a Worcester 9.24, but looking on net for help it doesn't seem to match! Mine has one dial (temp) and a pressure guage, and two lights, orange 'standby' and green 'demand'. Behind a lift down flap is an electronic programmer. The display indictes no faults just time and programme.

Yeah but prolly have to wait till after Xmas when the plumbers return from their three weeks on Bondi Beach....

Re: leak see above...

I reckon, bearing in mind how water spreads when on the floor (laminate floor) I reckon I lost about a quarter of a pint at most. Leak is tiny, about one drip every 30 secs?

Anyway, the good news or bad news if I don't want to be labelled a thicko! I climbed up to see if pilot light was on (damned thing is mounted really high up and I'm 6'4") and it wasn't. Followed the instructions on the back of the panel to relight it and voila, so far so good. Hot water is well, warm at the mo, rads heating up. Pressure is rising to 2.2 bar at the mo, I think I may have been over-jealous in refilling. Will it release the extra pressure automatically?

First thing I would normally check is pilot light, but the water leak and this being my first experience of sealed system through me! Honest!

So hopefully I should be ok till after the hols and get the valve sorted and rebled.

Thnaks for the help, hope this can help others - ie check the obvious!

Ste

[Andrew Gabriel]

There are about 20 drips per cc, so that's 1cc every 10 minutes, 144cc per day, a litre a week. If there's, say, 2 - 4 litres of water pushed into the expansion vessel, you'll empty it and depressurise the system in 2 - 4 weeks at that rate.

Slow leaks like that can dry on the hot pipework before they even get to drip off and stain something, which can make them hard to find.

Yes, but if there's some other weak link in the system, it might do so through that before the pressure relief valve operates.

1 bar is normally enough for a cold system, unless you have any central heating pipework more than 30 feet above the guage.

[John Rumm]

Sounds like the valve is knackered and needs replacing in which case. Easy enough job to DIY if you can't get a plumber.

The work by a wax capsule in the valve head expanding and pusiong down on the pin. With the pin fully down the water is shut off, with it fully up the valve is full on. You may find you you can bodge this with some leak sealing epoxy for the time being. Or just take the thermostatic head right off to leave the valve fully open if it leaks less that way. (If the rad gets too hot, then you can turn it down a bit with the lockshield valve at the other end)

If this was only a slow leak, then chances are you have not lost much water from the system. Once the pressure is down, less comes out - especially on an upstairs radiator since there is less "head" of water in the system above you.

I just had a look on their site

at some of the user guides. I notice the one I looked at (a greenstar HE combi) had a temperature knob that had a reset position at the low end of its travel. Hence to request a reset, you turned it right down to minimum, then back to your desired temperature.

If that does not help, have a look and see if you can find a closer match to your boiler and hence a manual for it (assuming you don't already have a user manual that is! ;-)

(If your lucky someone like Ed or Geoff will see your post and know exactly what is needed for this boiler)

OK nothing much to worry about from the inhibiter point of view then. I would expect you would need to loose a few pints in total to drop the pressure to zero though. Eaiser perhaps if it is a small system (i.e. not many rads) since the amount of water in it will be less.

Ah, should have read this bit first... ;-) Sounds like you are mostly sorted.

Many boilers you would fill to about 1 bar when cold, they will then rise to 1.5, perhaps 2 when hot. Some want more however. There is a pressure relief valve which will open at 3 to 3.5 bar typically. It is better to not alow this to operate if you can though, since it is possible for these to leak afterwards if their mechanism does not reset correctly.

If need be you can drain a little from a bleeding valve, or drain point. The drain point can often be opened with a spanner or pair of pliers if you don't have a key for the bleeding valves. Beware, the water will stain if you spill it on a carpet though!

[BigWallop]

But an increase in pressure could also increase the rate in which the leaking part spouts water. At a lower pressure the part may not leak at all.

[ski]

Have a look for an overheat switch which may have tripped 'cause of no water. Sometimes they are a tiny red button inside the front cover

[raden]

In message , Ste Kearney writes

Hiding to nowhere ...

the 9.24 has no permanent pilot, it's electronic

there are two pcbs inside, a blue sequence (ignition) board and a white control board (~ 3" by 6" with a transformer and two relays on). I see a lot of control boards with water damage, check that first

Do I assume that you don't have a manual for the boiler ?

Where do you live, I probably have manuals for the complete range of

9.24s (there are several versions). I am in Watford

[raden]

In message , ski writes

Ian, you're a very naughty boy

Absent without leave AND top posting

how are you? Long time no see