yeah it is a shame the fan got broken. im hoping it is not going to be a problem, i think it will be ok because it used to be running in an elnclosed box inside the boiler, where there is little air circulation. i will be running it in the open air with more air moving around it. i will test it to see how it does.
i wish i still had the cover plate. i have no idea what size the hole needs to be. i could make somthing out of plastic or ali, but i dont know how to test it other than just feeling the output with my hand.
thanks for all your advice guys! much appreciated.
i have mounted the fan, wired it all up, and tested it. it worked fine.
its all safe with rcd, earthed cable, and insulated crimped spade ends. i want to add a foot switch when i find a suitable one.
an electrician friend down the pub said i can easily fit a speed controller. would this be a dimmer type switch, or a specific "speed controller"?
anyone have a rough idea as to the tyere diameter i should go for? my intuition says just use one the sameish size as the fan output. is there any befenfit to reducing it down?