BOFA Filters

[TimBobTastic]

Hi

I have one of the BOFA extractors (it's excellent) and the fan speed is increasing (5 lights now), so I guess I will need to be buying some replacement filters very soon. My question is, do I need to purchase both or just one of the two?


I have had the machine 18 months and cut mainly plywood and occasionally acrylic (never MDF).

Thanks in advance

[TimBobTastic]

After talking to HPC I decided to change both filters... (They are always very helpful).

I have to say, I totally forgot how quiet the BOFA filter unit is when you have new filters fitted... It is whisper quiet ad makes less noise than the laser!....

I was a little taken aback by how quickly lights 5 and then 6 came on compared to the first 4 (the final light was on within 2 days of the 5th).... I would love to know the maths behind it... perhaps I can preempt my next filter change a little.

Next time, the filters will be ordered when light 4 first appears.... that will give me plenty of time and ensure I have filters to swap out without down time, when the need arises.

All in all, the BOFA filter has been a great addition to the workshop, well worth the investment, mainly because it allows me to cut in the middle of a residential area without the risk of annoying the neighbours with the smell of burning wood or acrylic... especially during the summer. It also gives me peace of mind for my own health and well being...

[JamesW]

Hi TimBobTastic,

For the last 18 months or so I've been running a BOFA filter, and I *think* that you can reduce your costs and extend filter life by replacing the "Deep Pleat Duo" pre-filter more frequently than the more expensive carbon filter.

I ate through my first pair of filters in about 3 months - and now, more than a year later, I have replaced the prefilter twice, but not needed to replace the carbon filter yet.

I suspect that this is dependent on what you cut. If it produces lots of smoke and dust (eg: MDF) then it'll clog the prefilter quite fast. If you cut lots of perspex, then the prefilter won't be that much impacted, but the carbon filter will get saturated quicker.

This is mostly guesswork, but informed by an extended chat with BOFA. What seems to be happening is that running the unit on speed 6 for a while (i.e. for weeks, rather than a day or three) encourages grot to make its way through or around the paper pre-filter, allowing it to start knackering the carbon filter faster. If you replace the pre-filter smartly, it protects your carbon filter for longer. The alarm will only go off after the carbon filter fails.

Even if you only extend the life of your carbon filter for a month, you'll save about £30 per year! I suggest next time you buy a filter, buy only the pre-filter, and see how much longer you can keep the carbon one going for. Then when the alarm sounds, replace the carbon filter. Then when you get to speed 6 again, replace the paper one, and so on. What have you got to lose? There's no point replacing a carbon filter before you have to. If your experience is like mine, I reckon you'll end up buying filters in a ratio of about 3 paper to 2 carbon, saving yourself about £80 per year - which is worth having. Just make sure you don't end up spending that on delivery costs!

I'd be interested to hear what your results are.

Hope this helps!

James

[TimBobTastic]

Hi James

Thanks for the detailed response, I will definitely be trying that when my filters need replacing again. I cut a mixture of ply and acrylic (about a 70/30 split) so I may be able to save a few quid in the long run... (I will try anything once)

Regards
Tim