Help. Burst radiator.

[harbingerofdoom]

Nobody was in the room where it has burst but as we walked by we could hear dripping. As it's been raining non stop....
I think that we have isolated the radiator (finding the spanners was interesting!)
What would you do next?

[nocake]

Buy a new radiator...

[harbingerofdoom]

We can't find one the same size.

[nocake]

Hmm, that's a problem. As long as it's turned off at both ends it's not going to leak any more so you've got some time to find a new one. How're your plumbing skills? You need to get one a different size and add some extra pipework.

It's a quick job so if you use a plumber it shouldn't cost much. You can save some money by removing the old one and putting the new on the wall.

[harbingerofdoom]

After telling my DH several times that he is NOT to touch it,he has agreed that he is not a plumber . I can just imagine the mess he'd get us into going on past experience.
I've found a plumber and it sounds a nice simple job for him!
Out of interest,how common are burst radiators?

[nocake]

Not common but if you don't have an anti-corrosion chemical in the system they will corrode from the inside.

[harbingerofdoom]

The weird thing was that there was no black/rusty water at all.

[nocake]

That's because it's all lurking in the bottom of the rad, waiting to pour all over your carpet as soon as you lift the rad off the wall

[harbingerofdoom]

Thanks for that! Will look forward to it.............haha Lots of old towels. Already lifted carpet.

[PigletJohn]

a tip...

when you take off a radiator, always immediately turn it upside down to carry out of the room. That way, the valve holes (or in your case the split) will normally be at the top, and unable to dribble sludge on your carpet. Black sludge is pretty well impossible to remove, and will stain most things, including rough skin and plastics.

A radiator in good condition will withstsand enormous pressure, so your almost certainly rusted from the inside. This is usually caused by a plumbing fault that allows air, or fresh oxygenated water, to enter the system.

An old system, with no corrosion inhibitor, will eventually rust away, but usually it will stop working due to sludge and corrosion blockages before then.

Assuming that all your other radiators are equally old, and have had the same quality of water circulating through them, they are likely to be equally rusty inside, so you should plan to replace them before they leak, and to get an experienced heating engineer to diagnose the (probable) leak or pumping-over problem that caused it, and give the system a through clean to remove the corrosion sludge that is probably clogging your boiler and making it bang.

If you recently had a modern boiler fitted to old radiators, the cause might already have been cured, but the radiators will still be corroded and weakened.

[harbingerofdoom]

Thanks for you post *PigletJohn, you have made some very good points that are worth acting on and remembering.
What has happened is a warning, as the rest are the same age. Will try to prevent further problems by getting the whole system looked at properly and not just dealing with the one radiator.

[cantspel]

I have just had 7 large old panel radiators replaced with new convector rads. All the pipe work needed changing as the old one's were imperial and the new metric and i paid £1100.
2 others to be replaced but they will be done as part of our on going building work.

[PigletJohn]

All the pipe work needed changing as the old one's were imperial and the new metric and i paid £1100

'mmmm

half inch imperial, 15mm metric, direct fit (i.d. and o.d.)

three-quarter inch imperial, 22mm metric (needs a new olive)

one-inch imperial, 28mm metric, needs an adaptor

there must surely have been some other reason for the £1100?

Were the old pipes copper, or steel?

[cantspel]

No pipes didn't need changing.

The rads fitted were like these

www.screwfix.com/p/kudox-premium-type-22-compact-convector-radiator-white-600-x-1800mm/87748

and pipes were more than the odd inch out as we replaced small panel with large convector. The £1100 included the cost of the rads

[harbingerofdoom]

How often should a corrosion inhibitor be added to the heating system?

[PigletJohn]

not very often. It mostly needs topping up when it has been lost due to leakage, or lost its power due to aerated water enering the system, in either case the fault needs to be corrected first, and then the inhibitor added. It is possible to buy test kits for a few pounds from a plumber's merchant, if you have no faults (like me) you might add half a litre every five years or so.

If corrosion is occurring (or aerated water entering) then you will have to bleed the radiators, and gas will come out (it is actually hydrogen, and is inflammable, but there is usually very little). If you need to do this more than once a year, or you can tell that there is more than an inch of gas at the top of one or more rads (making the top cold) then something is wrong and needs fixing.

More likely, add new inhibitor each time a fault occurs or you drain some water, e.g. you take a rad off for redecorating or have to change a valve.

If you have a sealed system (with a pressure gauge on the front of the boiler) there is no reason air or fresh water should enter the system, if you need to top up the pressure more than once a year, there must be a fault.

If you have an open-vented system, with a feed and expansion tank in the loft, tie up the float and bale out any dirty water and mud from the tank before adding inhibitor.

The leading brands are Sentinel and Fernox. There may be test kits for other brands, I don't know.

[harbingerofdoom]

Yet again,you've come up trumps!
I've been down on my hand and knees looking at the other radiators. Most seem fine but the bathroom one looks similar to the one that's gone. Rusting on the bottom seam.
Both in cold/steamy places.

[harbingerofdoom]

I little update. The day after the new radiator was installed we woke up to puddles at both ends. Radiator isolated again, on the coldest night so far.
Plumber did come back and use enough plumber's tape this time. T'was also leaking at one end where he'd bent the pipe.
Inconvenient for us but a waste of time for the plumber (having to drain the radiator again). Job done in the end..................

[PigletJohn]

I use PTFE tape. I know some old pro plumbers who refuse to use it, claiming that their joints never leak and tape is the sign of an amateur. They are wrong, professionals' joints do sometimes leak, and PTFE is very good for preventing it.

Did he wear a cloth cap and a blue boiler-suit?

[harbingerofdoom]

He did explain that you can't get 100% seal with metal to metal 'always'.

Is this your foray into the 'Style and Beauty' section? No he wasn't,but it might be the next 'look'. It may well be the look,who knows.......................

[harbingerofdoom]

Update

Another one has burst.

This one has caused a lot more damage/inconvenience.

Getting hacked off now. What's going on?

[PigletJohn]

all the same age, all had the same water going through them = all equally rusty inside.

Was your system converted from an old boiler to a modern one, keeping the same radiators?

[harbingerofdoom]

All radiators the same age. So yes to no1.

No conversion,new throughout.

The previous occupant had a tiny 'back' boiler and two radiators.

[PigletJohn]

when was the boiler fitted? How old are the radiators?

has the boiler got a pressure gauge on the front, and what does it read?

have you ever had to top up the pressure?

if you look at the pressure relieve valve outlet which usually pokes through the wall behind the boiler, is there a water stain on the outside brickwork?

[harbingerofdoom]

The boiler is a Prima 80 gc

[PigletJohn]

one of these?

it looks rather like the Potterton Profile 100e my old mum used to have. An open-vent boiler with a cast-iron heat exchanger. 60% efficient and much loved by older heating engineers, is fairly simple and reliable, will last a long time. In the region of 20 or 30 years old.

As it appears to be open-vented, there will be no pressure gauge. There will be a feed and expansion tank in the loft, about 18"x12"x12" having a ballcock in it like in a WC cistern.

Go and look in this tank. I think you will find there is a lot of brown mud in the bottom. Possibly a blanket of fungus on the top, especially if there is no close-fitting lid. Look at the ballcock, is it dripping? How deep is the water, and is it near the overflow pipe? Is there any sign of a an inhibitor label on or around the tank, or a plastic bottle cast aside, probably with the name "Fernox" or "Sentinel" on it? Is there any date or indication of age on the label or bottle? The label might be on or close to the boiler or the cylinder.

Has the system been drained in recent memory?