Bathroom Downflow Fan Heaters

[Steve]

It got cold here last night and I woke up at about 3.15am with stomach cramps and starting an attack of Irritable Bowel Syndrome (IBS) - ended up sitting on the bog for 45 minutes!

I got to thinking - why do fan heaters have thermostats that turn down once "the room" gets warm? In reality, "the room" is usually nowhere near warm.

Downflow fan heaters are usually mounted at about head height or slightly above and, as we all know, hot air rises, so when the heater itself thinks it's hot enough it automatically switches the 2kw output down to 1kw - but at "sitting on the bog" height it was fekkin' freezing!!

[Brian_Gaff]

Actually its not much better for floor mounted ones either I find, You seem to get draughts setting it off randomly, or the hot bit is higher than you are. It would be very interesting to be able to see a thermal image of a given room with a given heater.

Maybe we need not just the heater, but some kind of air circulation system to take the hot air and pump it to low vents so the air is more evenly mixed. the other way is to use a remote thermostat. I'm surprised we have not seen Wireless each used in fan heaters by now, so you can put the thermostat in the coldest place. Brian

[Andrew Gabriel]

It's because they are often fitted into rooms which are far too small to operate a 2kW heater continuously, without getting far too hot.

One problem it might have is the connections to the internal stat going a bit high resistance, which will cause the stat to self-heat due to the current flow and cut-off prematurely. They're usually

1/4" car blade type connectors. Just pull them off and push them on again, and if they're not a tight connection, take them off again and pinch them slightly tighter with a pair of pliers (be very gentle, the tiniest pinching closed makes them much tighter, and you may struggle to get them back on).

I recently fixed a Smeg oven with this fault on the cabinet overheat stat - it would cut out about 5 mins after switching on. This stat usually only opens if the cabinet cooling fan fails, but this one was happening too quickly for that and the fan was working fine. Inspection revealed the stat connections were overheating due to the current and connection resistance having gone high (and melted the plastic cover and cable insulation).

[Chris Hogg]

I gave up on fan heaters in the bathroom years ago for just those reasons. We currently have a c/h radiator set on low just to keep the chill off, and a wall mounted infra-red quartz radiant heater for instant warmth:

[Steve]

Andrew Gabriel was thinking very hard :

Thanks Andrew, it's good to know the reasoning behind it although I do think the manufacturer's are being a bit 'overly protective' of us because I, and most other people I would think, am capable of thinking "Ooh, it's getting a bit hot in here, I'd best turn the fan down/off." I was blue and shivering like a leaf by the time I could get off the loo 8-o

[Steve]

Cheers Chris, I may just go that way very soon.

[Tim+]

Sounds more like a case of food poisoning than IBS.

Tim

[Steve]

Nah, definitely IBS, suffered from it for years. I was only blue and shivering because it was cold at loo level ;o)