heater blowers

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ian bilsby
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heater blowers

Post by ian bilsby » Tue Oct 30, 2018 6:33 pm

My heater blowers are not coming on straight away in either auto or manual modes would this be connected to the FBH or another fault they all fire up after about 5 minutes of driving but this isn't ideal in the cold weather when trying to demist a steamed up windscreen also my windscreen is only heating up certain sections does this mean its fubared or could it just be connections .
Many Thanks Ian
P.s where can i get a basic fbh controller from using the third button on remote..... :headbang: :headbang: :headbang:

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Re: heater blowers

Post by PillowSmuggler » Fri Jan 11, 2019 9:05 am

Looks like you have waited for a while for a reply, so on the off chance you're still looking for one, the delay in running the fans appears to be intentional as mine has done this from new. If I had to guess, it's waiting for a glimmer of heat from the engine before it gently blows humid air from outside onto the super-cold windscreen so it doesn't make it wetter.
If you put it in manual and turn the fan speed to max it should blow regardless.
If you press the Programmed screen clear button above the demister buttons it should also run the fans at max straight away, and in my experience this is the best option for clearing the screen (other than running the FBH first of course!).

In theory, if your alternator isn't kicking out enough amps/volts then the car may decide to prioritise where the power goes, but I'd have thought that the screen clearing would have priority over the heated seats etc. I have a permanent volt meter attached to mine, and when very very cold the alternator will hang at around 10.5 volts for up to 30 seconds before the volts slowly creep up, then they'll suddenly jump to 15+ volts at which point you can hear the fans surge. To help the car out on such cold starts, I carefully hold the revs at 1500 which gets the alternator warmed up much quicker and gets the oil pressure up to get it round the engine.

The windscreen is covered by two separate rectangular demister elements, which means there's a vertical wedge shape in the centre of the screen that has no elements in it, and this will be the last to clear and will leave a nice ice patch to kill your wiper blades on. That gap is normal The individual finer-than-hair element wires can burn out, though my screen is now 12 years old and just has a few slower to clear vertical bands. I think they're tired rather than them being broken as they still eventually clear evenly rather than clearing in from the edges, so possibly you're seeing something similar? All the elements are bonded inside the glass so unless there's an obvious left or right hand side not clearing then it's either put up with it or replace the windscreen.

There are several FBH solutions out there, some commercial, some home made but I'm afraid I don't know specifically which of them uses the third button as a switch.

Regards, Dom.
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Re: heater blowers

Post by anglefire » Fri Jan 11, 2019 11:36 pm

PillowSmuggler wrote:
Fri Jan 11, 2019 9:05 am

There are several FBH solutions out there, some commercial, some home made but I'm afraid I don't know specifically which of them uses the third button as a switch.
I think the only commercial one I can think (But I'm well out of the loop these days!) of that uses the third button is Pete Bells remote FBH - it was certainly an option a year or two back following a home brewed one that used it - you have to program the third button to turn the lights on, which is all in the user manual.


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