Electronic air filter question

[Qballgreg]

Just purchased a 10 year old home and discovered during the inspection that the air handler is new, but that there is a slot for an electronic air cleaner, but the slot is empty...meaning there is no electronic air cleaner/filter. There is a pleated filter in the ceiling leading to the air handler. Also the HVAC unit is a heat pump, if that matters. My question is whether I need to purchase an electronic filter, or is it okay to leave the space open and just use the pleated filter with a high MERV rating?

[t527ed]

measure the cabinet from the air cleaner and see if you can get a 4" or 5" pleated filter to fit it.
if you can put one there then remove the one from the filter grill.

[Qballgreg]

Not quite sure what you mean...the Filtrete filter I am currently using is a 20x30x1 MERV 12 in a drop down grate from the ceiling. I presume the air handler is above that with the open hole where there used to be an electronic filter. Are you suggesting removal of the filter I am using and just put a smaller one in the air handler?

[t527ed]

the frame size may be smaller, probably 16 x 25 or 20 x 25 but at 4-5" thick it will give you more filter surface area and less resistance. also having the filter right at the unit will trap any dirt that gets into leaks in the return duct after the return grill.

[Qballgreg]

Thanks...are filters of that thickness readily available at a Home Depot or Lowe's?

[BamaCool]

Thanks...are filters of that thickness readily available at a Home Depot or Lowe's?

No. Must get through local dealer. If you have a 3 ton on that 20x30x1 filter, you will be calling a contractor to come fix your unit anyway.

[second opinion]

Thanks...are filters of that thickness readily available at a Home Depot or Lowe's?

Yes in most locations.

[Qballgreg]

Why will I be calling a contractor?

[Qballgreg]

I just checked the unit and it is a 4 ton unit....so does that make a difference with the 20x30x1 filter?

[BamaCool]

I just checked the unit and it is a 4 ton unit....so does that make a difference with the 20x30x1 filter?

Big difference. 3 ton filter size. 4 ton unit - with a PLEATED filter = BIG PROBLEMS

[Qballgreg]

Although I appreciate your reply, it does no one any good to say something is a BIG PROBLEM unless you have the expertise to explain WHY....

[BamaCool]

4 ton requires 800 sq inches of non pleated filter area. (If filter is 1" thick). You have 600. Not enough for 4 tons. Causes air flow restrictions which in turn causes premature wear and tear on all parts - electrical and mechanical. Causes abnormally high head pressure in heat and low suction pressure in cool. Also increases power usage.

[Qballgreg]

Great info....so the obvious question is....what is the recommendation?

The air handler has a Honeywell electronic air cleaner...would a pleated filter (20x25x4 1/2 MERV 12) in this unit be acceptable and does it relate to the issue of the 1" filter in the return air grate in the ceiling leading to the air handler?