The house we live in has an old electronic air cleaner attached to the furnance. It's a Honeywell F50E 1182. We have lots of wildfire smoke in the PNW right now and am wondering if using this system or putting a regular pleated insert in like they do in this video would be better at filtering out wildfire smoke. I have a 20x20x4 filter I could put in if so.
The electrostatic filter will be your best option to filter the smoke, you may need to clean it every week until things clear up, putting a filter that has a finer particulate rating than your system is designed for can cause problems. Your best bet now is to turn the fan on all the time so your air is getting constantly cycled over the grid. If you haven’t cleaned the filter hose it down now so it will be functioning at its peak performance. I have a granddaughter that has serious as a problems and the electrostatic on the furnace keeps the air inside clean enough she doesn’t end up in the hospital. The last time I also closed down the make up air intake as to reduce the amount of fresh air because of the smoke load. With the electrostatic you don’t want to slow the air exchanges these filters when clean are more effective at reducing smoke. A high density filter reduces the air exchanges so it is not as good even if it could take out the finer particles.
Smoke particles are on the order of 1 micron. A "pleated" filter is good down to about 3-5 microns so NO, that will not filter out the smoke. Some will get through.
What you need is a HEPA filter, which usually involves adding a HEPA filter unit into your system and these are effective down to about 0.3 microns.