Electrostatic Air Filter Installation

I have a Lennox Furnace and the air filter was serviced by removing the front door. It was a real difficult process to pull out the filter and also to replace it (making this process worse was the fact that I am using the rigid/metal electrostaic filter).

So, my service man said he could cut a hole in the ductwork and I could service it easily from there. It obviously is much easier but the concern I have is the hole he cut is 1/2" wider and 1" taller than the actual filter dimensions. I felt that this would allow air to be sucked from the basement and also around the filter (instead of through it) as it is no longer a tight fit. The service man claims that the dirt is attracted to the filter and that I should not be concerned about the size of the opening.

Any thoughts? is this a problem?

 

He had the right idea but I agree with your logic. Air will move where it can and what you will find is that some dirt stays in the filter and some gets by it. What I do is make a 1" 'U' channel that fits the filter and then find a way to make that fit airtight into the return. In your case, would you be able to take a piece of plywood and block off the area that isn't covered by your air filter? All you need to do is make it impossible for air to get around that filter. Next issue will be freeze ups on the air conditioner and low air flow because of the filter. They are pretty restrictive.

 

You dont say what model you have here. But if it had the large wrap around filter that you put over the wire frame Id go back to that for sure. like ken dont let air go around the filter. ED

 

Thanks guys, that's what I was afraid of. Anyway I have a regular box filter, as I did'nt want the box contraption that Lennox normally provides. Fortunatly, I can go back to installing the filter the old way and just ducttape the hole in the ductwork.

Oh well!!!