supply air question

[bugstein]

I have a brand new Goodman all electric 5 ton heat pump package unit on my roof. I have two 16 x 20 supply air filters (one in front of a vent and the other on the opposite side of the same vent in my house). The tech told me to use the fiberglass filters, I assume to increase air flow. He told me my equipment would last longer that way. I prefer the quilted filters, about MERV 7. Are these two supply sources enough to properly supply air to the 5 ton unit. I upgraded from a 4 ton GE (non heat pump) package unit.

[TwincamDave]

what size duct is behind the filters ?

[beshvac]

16x20 Hart and cooley grills max out about 770cfm before the velocity gets to high.

So for 4 tons at 1600 cfm they were already a little light....

Why did you upsize a ton? Did they check that the duct would handle it?

Pics would help.

[wahoo]

1' quilted (accordian type) air filters will greatly decrease (lower) your air flow. That's the main reason the installer told you NOT to use them. I can't imagine that two 16x20 air inlets will supply enough air for a 5 ton, but it'll be much worse if you go to 1" high MERV air filters. Use the cheaper filters and spray them with Endust when you put them in, much cheaper and not nearly as restrictive.

[bugstein]

the duct is also 16 x 20. I can add another grill/filter to the other side if necessary....

[bugstein]

The coverage area was slightly underserved by the 4 ton--it was installed about 35 years ago. I also wanted the quicker heating and cooling of the 5 ton. I don't recall if they checked the duct--I had several installers out here. What happens if the velocity gets too high ??

[bugstein]

I have been using the quilted for about a month--since I started using the unit. Is MERV 7 high--I see them at 13 and 14 ?? How effective will the fiberglass filter sprayed with endust be at catching small micron particles ??? How often would you change them ??

[beshvac]

x

[beshvac]

The coverage area was slightly underserved by the 4 ton--it was installed about 35 years ago. I also wanted the quicker heating and cooling of the 5 ton. I don't recall if they checked the duct--I had several installers out here. What happens if the velocity gets too high ??

It just pulls dirt thru the filter.....

[wahoo]

Any 1" filter that catches "small micron" particles will reduce air flow significantly. If you want a high efficiency filter, then go with the 5" filter made not to restrict air flow and still have high Merv ratings. 1" pleated "high Merv." rated filters are simply horrible products and will cause you to have decreased air flow and INCREASED operating cost along with decreased equipment life. I see these things EVERYWHERE in the discount stores, and we have a LOT of complaints/problems relating to their use. If you MUST use them, then change them each week as they'll plug that quickly. Kinda like the filters you use in your coffee maker since most are made from filter paper anyway. Horrible product. You simply can't get the performance of a high dollar filter such as the 5" units with a cheaper 1" product. There is a reason the 5" pleated filters have been around so long with such success. They work well for the purpose they are intended to be used for. Sure the 1" filters will "trap" more particulates.....a simple sheet of white typing paper will completely stop all particulates from entering your HVAC system. These 1" filters use high density filter material with inadequate storage surface area, so they quickly plug immediately upon use. We've seen them plug within just a few days of installation in a high traffic home especially if they have pets or numerous children. Years ago we offered a product called "filter coat" that would increase the dust catching capacity of simple fiberglass filters. We just recommend Endust now and folks who use it swear by it.

[kdean1]

Honeywell makes an extended media filter that will fit into a filter grille. Models FC40R & FC20R

[beenthere]

The coverage area was slightly underserved by the 4 ton--it was installed about 35 years ago. I also wanted the quicker heating and cooling of the 5 ton. I don't recall if they checked the duct--I had several installers out here. What happens if the velocity gets too high ??

Good chance it was the dirty coil and blower wheel that caused poor cooling.

Go look at your air filters now. Are they bowed in at the middle. if so, they are too small and too restrictive.

[bugstein]

I'll give the coated fiberglass a try. How long do the 5" filters last, and would they fit in my current vent grills ?? Thanks for all your help....