Any benefit to adding 5-inch media filter when new system is installed?

[jtrammel]

If U use filters in the conditioned areas or in the Return ducts, U should not use a filter in the furnace/air handler; - double filtering increases the static pressure way too much.

Two large filter racks in the conditioned area with the deep filters will do a great job filtering, along with being very efficient.

As long as you design the duct for it it will not increase static to much. I have a customer that I installed has 3 filter grilles with 1" fiberglass and a 5" at furnace. Runs at .5 static

[jtrammel]

As long as you design the duct for it it will not increase static to much. I have a customer that I installed has 3 filter grilles with 1" fiberglass and a 5" at furnace. Runs at .5 static

They have cats and dogs so they use the 1 inch filters to catch hair and change them once a month. The 5" gets changed once a year at fall prev maint and it never looks dirty

[RoBoTeq]

As long as you design the duct for it it will not increase static to much. I have a customer that I installed has 3 filter grilles with 1" fiberglass and a 5" at furnace. Runs at .5 static

It is always a bad move to have two points for filtration, and it is completely unnecessary. I'd like to know where you are measuring the SP on this system.

[jtrammel]

Return plenum between filter case and blower compartment and high temp limit switch in heat exchanger.

[RoBoTeq]

Return plenum between filter case and blower compartment and high temp limit switch in heat exchanger.

Must be an oversized return ducting and filters, which is good. Still, if you have a filter grill, why do you need another filter? If the duct is leaky, then the filter grills are useless.

[jtrammel]

The customer was worried about pet air getting into the newly installed and sealed duct from the filter grille to the furnace media filter and didn't want the expense of 3 fc40s so we sized it accordingly and did it that way.

[RoBoTeq]

The customer was worried about pet air getting into the newly installed and sealed duct from the filter grille to the furnace media filter and didn't want the expense of 3 fc40s so we sized it accordingly and did it that way.

Many things can be done for specific issues. This should still not be promoted as something that is normal to do because it will adversely affect most systems.

[tedkidd]

.5 ESP with two filters, so just barely makes spec. I wonder how good it would be with one point of filtration.

Of course you need to satisfy customer OCD without or they might find someone else.

[jtrammel]

I wasn't promoting it I was just saying that it can be done if it was designed to do so. Same with 3m filtrete filters. As long as its designed for it then it's ok. I agree that 99% of the time the duct is not designed for restrictive filters and it causes problems.

[Florida Joy]

I wasn't promoting it I was just saying that it can be done if it was designed to do so. Same with 3m filtrete filters. As long as its designed for it then it's ok. I agree that 99% of the time the duct is not designed for restrictive filters and it causes problems.

Hey ya'll, I appreciate all the back & forth discussion my question has generated. It's been enlightening!

I've decided to stick with the two 20x20 filter grilles and NOT install the 5" media filter, because it would require potentially problematic modifications to my air handler stand that might reduce return airflow.

I've also decided to try returning my recently purchased "back-up stock" of Filtrete 1" filters to Sams's Club and get the 5" if I can find them at any HVAC warehouse in my neighborhood. My son is the RE Michel manager in Orlando, so he can probably bring me one the next time he comes with the kids for a visit with Grandma.

I've tried finding the 5" filters for 1" filter grilles in local retail outlets, to no avail. Some thought I was dreaming and said there was no such thing. Others said they've not been able to "get them in" yet. I'll call around on Monday to some of the local HVAC warehouses.

Thanks everyone!

[second opinion]

Hey ya'll, I appreciate all the back & forth discussion my question has generated. It's been enlightening!

I've decided to stick with the two 20x20 filter grilles and NOT install the 5" media filter, because it would require potentially problematic modifications to my air handler stand that might reduce return airflow.

I've also decided to try returning my recently purchased "back-up stock" of Filtrete 1" filters to Sams's Club and get the 5" if I can find them at any HVAC warehouse in my neighborhood. My son is the RE Michel manager in Orlando, so he can probably bring me one the next time he comes with the kids for a visit with Grandma.

I've tried finding the 5" filters for 1" filter grilles in local retail outlets, to no avail. Some thought I was dreaming and said there was no such thing. Others said they've not been able to "get them in" yet. I'll call around on Monday to some of the local HVAC warehouses.

Thanks everyone!

I've tried finding the 5" filters for 1" filter grilles

Think real hard about this.

[jtrammel]

Ac supply houses around here carry them in common sizes. Retail stores usually don't carry anything but 1" filters. RE Michael should have them if not I know they can get them.

[RoBoTeq]

I wasn't promoting it I was just saying that it can be done if it was designed to do so. Same with 3m filtrete filters. As long as its designed for it then it's ok. I agree that 99% of the time the duct is not designed for restrictive filters and it causes problems.

I think a few philosopher/theologian types have commented on this sort of contradiction of others by using an out of the norm example;

"Ye know nothing at all, Nor consider that it is expedient for us, that one man should die for the people, and that the whole nation perish not."

]"This thought comes to us from Caiaphas, the High Priest mentioned in the Gospel of John.

"Even supposing the chief good to be eventually the aim for the individual as for the state, that of the state is evidently of greater and more fundamental importance both to attain and to preserve. The securing of one individual's good is cause for rejoicing, but to secure the good of a nation or of a city-state is nobler and more divine."

This comes to us from Aristotle, in his "The Aim of Man".

A more contemporary quote is from Spock in Star Trek: The Wrath of Khan;

The needs of the many, outwegh the needs of the few, or the one.

Our needs for this thread are for the many, not the one that contradicts the most logical suggestions and solutions.

[Florida Joy]

I've tried finding the 5" filters for 1" filter grilles

Think real hard about this.

??? Sorry, I'm a little dense at times. What are you trying to say?

[RoBoTeq]

I've tried finding the 5" filters for 1" filter grilles

Think real hard about this.

What's to think about? This type of filter is available and has been posted in a video on this thread. All it is is a 5" filter that goes through the opening of the filter grill's filter rack with a 1" filter type flange that fits the filter rack. A pretty clever idea as long as the depth is available at the filter grill.

[Mr Bill]

All it is is a 5" filter that goes through the opening of the filter grill's filter rack with a 1" filter type flange that fits the filter rack. A pretty clever idea as long as the depth is available at the filter grill.

Well shoot the horse and slap me silly, that is a good idea!!

[54regcab]

What's to think about? This type of filter is available and has been posted in a video on this thread. All it is is a 5" filter that goes through the opening of the filter grill's filter rack with a 1" filter type flange that fits the filter rack. A pretty clever idea as long as the depth is available at the filter grill.

I just bent back the tabs that make the filter grill a 1" and put wood blocking in the "return box" to accommodate the standard 20"x20"x4" thick filters I use in my system. The local supply house stocks the 20x20x4 which is an added bonus.

[second opinion]

What's to think about? This type of filter is available and has been posted in a video on this thread. All it is is a 5" filter that goes through the opening of the filter grill's filter rack with a 1" filter type flange that fits the filter rack. A pretty clever idea as long as the depth is available at the filter grill.

I am well aware of doing it this way,a sleeve for the filter can be fabricated to support the filter provided the cavity is deep enough. Any sheet metal shop can make it.

[Florida Joy]

I am well aware of doing it this way,a sleeve for the filter can be fabricated to support the filter provided the cavity is deep enough. Any sheet metal shop can make it.

I'm not interested in jerry-rigging my filter grille with sheet metal sleeves, as you suggest, or wood blocking, as suggested by 54regcab. I want to use the 5" filters described in the video in my existing 1" filter grille, without modifications, since the cavity is deep enough. Tell me why I shouldn't do that?

http://www.youtube.com/watch?feature...&v=sOJ0dte_z-Y

[jtrammel]

I'm not interested in jerry-rigging my filter grille with sheet metal sleeves, as you suggest, or wood blocking, as suggested by 54regcab. I want to use the 5" filters described in the video in my existing 1" filter grille, without modifications, since the cavity is deep enough. Tell me why I shouldn't do that?

http://www.youtube.com/watch?feature...&v=sOJ0dte_z-Y

They obviously don't know what type of filter you are talking about.