Oil fired boiler problem


Growing old, and fast
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Well, a mere 7 years after installing my, oil fired, Bosch Greenstar Camray Utility boiler (with a lot of help dfrom this site), it has developed a problem- due to the cold weather.

Came home today and the radiators were fairly cold. Investigation showed that the condenser outlet pipe was blocked solid with ice. Ten minutes later, and with a smug look on my face, I started it back up.

It ran for a short while then gave up the ghost.

I checked the oil supply, working from the boiler towards the tank:
No fuel at the boiler.
No fuel at the filter (a small amount of water came out mind).
No fuel at the remote oil fire valve outlet.
Fuel supply getting to the remote oil fire valve inlet ok.

So, the remote oil fire valve seems to have operated (would it operate if the condensing outlet pipe was iced up?) and not reset (can it reset? Or is it a one off operation?)

Any suggestions would be greatly appreciated.... It's quite chilly.



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Does it have a plunger or button to re-arm it? Have you thawed it, and the pipe to it, out with warm water? If you have already covered that (and I’d somehow be surprised if not) then it’s likely stuffed. If so, can it be jammed open or replaced with a straight coupler (for a very short period of course) until it can be replaced?


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I'm not as bright as you think Paul, I've only just checked and yes there is reset button at the bottom but, after attempts to press it in- no luck.

I'm freezing cold, it's very dark out there and, snow is covering everything (ok, not everything, certainly not anything taller than, say, 5 inches, but it's making for an uncomfortable work situation), and the wind is whistling around my 'trossacks' (which emitted a pleasant tinkly sound as I walked)- so I have decided to call it a day, er- night.

I've switched everything off and me-n-SWMBO will hunker down for the night.

No central heating, no hot water, and a bath which refuses to drain (on account of a drain pipe which is frozen solid)

Tomorrow is, as they say, another day.
A day for thawing out safety valves with a heat gun, or for teaching fire safety valves that they can be replaced with short lengths of piping ( for a short period of course, until they can be replaced)

On a positive note, I made good progress on the Velo earlier.
Wheels and mudguards are fitted, as are the control levers. (cables later)

PS Thanks for your suggestions Paul.


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Dave , You say a small amount of water came out of oil filter, I'm now wondering if some water could also be inside the safety valve, this may only be a small amount of water, but if this water has now frozen perhaps it is this thats preventing the valve from resetting:nusenuse:, -----
Suggest you light a fire under it :eusa_whistle::eusa_whistle:, (or perhaps a kettle of hot water would be more preferable:thumbup:)


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Sorry you’ve not been able to sort it out, Dave. I reckon it’s probably frozen (and hope so too) and that a bit of WARMTH will get you up and running.

It strikes me that these valves, while important and given their importance, are pretty archaic. The regs around them (from the little I’m aware of) seem a bit half baked as well. Devices that are required by the regulatory body to be external and risk not functioning vs the same things situated internally but that are considered naughty by the regulatory body because their specs don’t suit a warm environment and therefore fail to fulfil the objective...:nusenuse: It seems that objective (saving lives) has been dealt a double whammy by the very people who are charged with fulfilling it - whether that’s due to folks being burned to death or being frozen to death!

Surely solid state, remote sensing devices should be standard issue, and I can’t see why such an approach isn’t mandatory (i.e. an external electronic temperature sensor which, if it gets too hot, tells an internal electronically controlled valve to shut the system down? Best of both worlds, relatively simple, low cost, easily integrated and reliable. Why do people have to be dealing with contraptions that are like something out of the world of H.G. Wells?

P.S. While you’re teaching the valve a jolly good lesson, maybe you could increase the ø of that outlet pipe?
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Ya know how brake fluid is hygroscopic - so you don’t get water pool in one place and freezing preventing the operation of the brakes?

Well isn’t heating oil, being basically diesel, hygroscopic too? So how could water pool?
Also, I’d doubt if the take off from the tank is at the lowest part of the system where water would collect if it did.
I imagine The flow of fuel through this valve would be relatively high, as I get the picture it’s an in line device.
So I’m wondering the likely hood of water pooling there in the first place.
Furthermore (I’m affraid, lol) isn’t the system relatively new, so that’s relatively quick to have a water problem.
Could there have been any ingress of water?

Secondly, in days of old, in very cold temperatures, the diesel would go rather waxy and prevent a vehicle from running?
I dunno why it don’t happen in motor cars now....?
I think we’ve established the problem is seemingly one of fuel supply
Have you ever heard of trace heating and insulation? (Not being sarcastic there or anything) it’s whats used in industry.

There might be a net forum for this sort of stuff..say oilfuelers.com. I don’t mind discussing it here, but fact is I’m only guessing.

Finally, I’ve just been outside, and the gale, it’s soooo cold. Yet only a mere minus 3.5° on the gauge.
Over an hour to get back from wolves tonight. That’s an average speed of just under 14 mph.
Traffic has ground to a halt, yet there is little really to prevent modest progress.
I dunno what’s its going to be like in the morning, but because I’ve left my tools at work, I’ll have to go in now. So no possibility of my opting out.
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Growing old, and fast
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OK you'se guys- here's the latest update.....

The house is warming up as I type.

A kettle of boiling water did the trick.

Permission given for you bunch to look smug... Very smug indeed.

Thank you.

I was up at 6.45 this morning sorting it out, but the eventual flow of kerosene from the boiler supply- kinda put a big grin on my fizzog.

In my defence, it was so cold and dark last night that I just lost the will....

Re water being in the fuel, the tank has been in situ for about 20 years, so I'm not overly surprised that a bit of crap has got in.

Re insulation, I followed the regs for burying the pipe deep and I also fitted it in a full sheath of plastic piping (to save it getting damaged), but there is a few inches of exposed pipework- which has now been addressed.

And no Colin, I've never heard of 'trace heating', which I will look into in more depth, but which looks , after a cursory glance, to be a bit more than I need.

Once again guys, many thanks. (SWMBO says thanks too)


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Phew! A nice, simple and quick solution. Doncha wish every problem was like that?

Keep warm both.:thumbsup:
To be honest cg, I'm not sure how wise you've been in posting.

Given that the country is about to run out of gas, I imagine youd have quite a full house by the time we've all descended.



Growing old, and fast
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I've counted and we have 8 ginger biscuits.... Descend if you wish.

Now here's an interesting one: SWMBO was talking about our problem to the couple who run the village post office- and volunteered me to 'have a look'. (village life eh?)

So I'm now looking at a 2 year old Mistral oil fired jobbie and water is absolutely pouring out of it.

I noted about 8 fittings that had verdigree and assumed them to be the problem. (NVG plumbing)
Then, after removing the air hose I noticed that the air intake to the burner was absolutely full to the brim with water.

Further, I tried to drain it off and it kept re-filling.

Suddenly the condensing pipe bowl started to overflow and the water absolutely surged out of the burner air intake.

The washing machine had just been switched on.....

I could only imagine that the burner had burnt through the boiler proper allowing it to flow out... Couldn't make any sense of the washing machine effect though.

I tidied everything up and left....

And I thought I had a problem.


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Dave, I suggest that this time you stay well away from it, You could soon find yourself in very hot water :)biggrin: ), but this time with the authorities that be,
Not sure your even allowed to remove the cover these days without correct certification :icon_writing:,

So suggest you bid them well, and run like hell !!
In weather like this I find half the battle is in even finding the drain cock in the first place!

I hope you recommended a boil wash?
That should heat the boiler a bit...