by ericmark »
Thu Mar 22, 2018 10:20 am
The earth wire simply put in a connector block or fold over and tape, clearly leave it there in case wanted latter.
Most fan will produce a back EMF when switched off, so be it a dimmer or not putting an LED bulb and fan on same circuit could cause a problem, it depends on how the LED is current regulated, however likely it will work. But any ones guess to how long.
There seems to have been a tradition to wiring fans to lights, the building regulations are split into parts, the Part P refers to electric but with the bathroom fan it is the other parts which become a problem. Can't remember exact wording but the main points are.
1) The fan must not cause fumes to be drawn into the house, in general not a problem with central heating, but gas fires often have what is called an open flue, not really open, it's just that they draw combustion air from the room, so extractor fans, tumble driers and like can draw fumes into the room.
2) If you have an opening window a fan is not required, so you can wire any way you want, but with out that opening window the fan needs turning on when items are used in the room, if no window then coming on with lights is OK. But if there is a non opening window, you need to be able to switch on fan without the lights. In real terms daft, as I know after a shower I switch on fan isolator and then flick lights on/off to help dry the room. But the reverse is also true, the fan does not need to be connected to lights, a simple push button for fan is enough.
3) Today we seem to be mad about not releasing energy, so there is a move to the heat recovery unit, idea is hot air going out heats the cold air coming in, there are two versions in general, those with two fans that pump air in and out, and those with a single fan which pump air one direction only and rely on pressure in room (or de-pressure) to force air in other direction. The latter use the pipe through the wall as a heat exchanger and look just like a standard fan.
Remember a tungsten light bulb only wastes energy if you don't want the energy it releases, so in a bathroom the inferred light actually warms out body direct, and so in the bathroom the tungsten bulb can be looked on as energy saving. It safes energy because the bathroom can be kept at a lower back ground temperature when not in use, inferred heat is instant so far more efficient.
I have changed to LED bulbs, not to save energy but to reduce maintenance, but if changing causes a problem, then simply answer is don't change, in doors changing to LED lighting only transfers where the heat comes from, since gas is cheaper than electric yes saves a little money but the lights are only used in the dark, so what we had was a boost of heat in the evening, the inferred heat does not work a thermostat very well, so we got warmer house in evening then in the day. So to compensate when fitting lighting which gives off no heat, we need to fit programmable thermostats.
