Leaky oil-filled electric radiator. Dangerous?

[Simon C.]

I've a free-standing [15 yrs old?] electric oil-filled rad in the spare room downstairs, what I pretentiously call my 'office'.

I notice the carpet underneath has developed a stain, puddle shaped. No real colour or smell, but I can only assume the radiator has leaked oil. The stain doesn't really bother me as its barely visible in the corner, but is it safe? I'll be repacing the radiator, but should I rip the carpet up too? Not likely to contain dioxins or similar nasties is it? The room is well used and don't want to end up poisoning our kids - or us really.

[Tabby]

At 15 yrs old, no, no PCBs/dioxins.

NT

[Simon C.]

contain dioxins or similar

Thanks for that. Do you know what sort of oil its likely to be filled with? Nothing else nasty? I get a bit paranoid about home safety after a near nasty fire a while ago [as mentioned in a prev thread] Its an 'EWT' radiator, German manufacture aiui.

[alexander.keys1]

contain dioxins or similar

I've come across 'EWT' fan heaters, they seem to be solidly built, some models with metal cases, I used to work in an asylum seeker's hostel, a nearby electric shop stocked them and they were popular with the residents, but not with the site engineer as they overloaded the rising busbars.... "THEY CANNAE TAKE ANYMORE CAP'N!", and indeed they couldn't, one day the busbars overheated and bent together.

As for leaking oil radiators, the liquid may be flammable, move it onto a non-flammable floor surface and contact the importer about finding an approved repairer.

[Tabby]

contain dioxins or similar

I don't know, I'd expect its the cheapest oil, mineral oil aka baby oil.

NT

[Michael Chare]

If you are using a heater that it is leaking oil I would say that your fears are not paranoia but fully justified.

[Tim Watts]

I doubt the oil is anything nasty. But it might cause damage to furnishings.

The big problem is that if the rad loses significant oil, it's going to stop working once the oil fails to be able to circulate properly. Then the OP is at the mercy of the overheat failsafe (assuming there is one[1]) .

[1] Don't assume anything. I had a couple of fan heaters that were of mid quality (not Honeywell good but the next level down). The sodding things had bottom air intakes to suck the fluff in which blocked the element causing local hot spots and resultant jets of red hot air that then melted the crap plastic grills or casing. No effective thermal fuse. IIRC they did have thermal fuses but those couldn't reliably detect local hotspots.

This year I have some De'Longhi oil rads - boy those are good. The panel arrangement (they call it the chimney - look for Dragon or Vento models) is bloody good. A 2kW unit that's about 600mm long really can put out

2kW without the internal stat cycling - unlike the cheap crap B&Q sell which are rated 1kW and probably put out about 300W based on the duty cycle.

[Tabby]

Loss of oil wont cause the thing to overheat, the stat will function as normal. Its only the element that'll overheat and die.

NT

[Tim Watts]

Starting a fire as it does so?

That's why I drew caution to the overheat protection vs the normal stat.

I have seen too many badly designed heaters to believe that all of them will fail safely.

[Tabby]

How is a non-flammable metal/sand heating element in an enclosed steel space going to catch fire?

NT

[Tim Watts]

Causing a hotspot on the dry stell casing next to it?

[Tabby]

Lets see if we can make some sort of estimate...

Normal case running temp 60C max to avoid burns Room temp 20C so normal case temp rise is 40C

Ignition temp of Paper: 450 =B0C (prompt) or 218=B0-246=B0C (eventual)

220C is 200C rise so to reach the eventual slow ignition temp of paper would require the case temp rise to be 5x normal.

At that sort of case temp I'm inclined to think there would be an awful lot of heating of the rest of the case by conduction, and even if the stat were in the worst possible place it should still detect excess temperature and cut out.

NT

[Andy Champ]

Presumably the element is at the bottom of the oil container, so the heat is carried away by rising hot oil.

As the oil level drops it will cease to circulate, the element now being near the top of the remaining oil.

The oil nearest the element will now receive the entire element output.

Do not leave it unattended!

Andy

[Tim Watts]

None of this would be a problem if regulations required:

a) High temp thermal fuse fixed to the element at the highest point (ie lack of oil detector)

b) Lower temp (just under the boiling point of the oil) thermal fuse in the oil close to the element.

That would constitute enough failsafes for me to feel happy. Alas sometimes you're lucky if you get any thermal fuses - or if you do, that they've been sensibly placed.

[ARWadsworth]

What! And end up paying more than £30 for a rad because of the cost of these safety devices?

At least you will be warm as you watch the house burn down:-)

[Tim Watts]

:->

Yes - the 30 quid fan heaters from Argos were good value - they fried after one year, for the reasons previously mentioned... Despite being run on a hard floor, not carpet. One melted a hole right through the plastic!

At least the rather more expensive oil rads I got shouldn't do that, and will find a second home in the workshop to be once I eventually get CH.

I know that was toungue in cheek - but for the nay-sayers (if any):

(In short - thermal fuses with various operating temps, 10A max normal operating current, wait for it...

42p+VAT each...

[Dave Osborne]

contain dioxins or similar

Transformer oil.

idea whether there's anything nasty in it, but older transformer oils contained PCB's, which are v. bad.

years old puts your heater at c1995, which is way after 1981 when the use of PCB's was banned in the UK. So very unlikely to be a problem.

[Tabby]

o contain dioxins or similar

Why do you think it would use transformer oil?

NT

[Ukjb]

replying to Tabby, Ukjb wrote: Oil by nature is flammable, explosive even, as the radiator looses oil the heating element will be able to heat the available oil to a hotter temperature, should the thermostat fail and the element be left on to long the oil could reach boiling point at which the vapours will be volatile, as the oil is lost natural air will be drawn in to replace the void, the internal atmosphere will become oxygen rich, this said their would be others signs like bubbling boiling noises, smell of the hot oil being burned off into the air long before the risk of fire, if the radiator is leaking get rid of it and buy a new one they are not expensive.

[Ukjb]

replying to Tim Watts, Ukjb wrote: This is all true, how ever given that their are millions of radiators fans and heaters in use today, and let's say they should all have 3 or 4 safety cut out functions on them we would be in dire shortage of radiator engineers as nobody would have a working radiator. We are talking about radiators here not a modern motor car