PSA: Check your filters

[Red Squirrel]

I built an air cleaner a while back for the litter box room to filter out smells and dust. It's a 3 stage system with dust filter, hepa filter and carbon filter.

Think it's safe to say it was time to change it. At least I know my air cleaner works well.

 

[BoomerD]

Easier to just not have a cat that shits/pisses in the house.

 

[Charmonium]

I change my filter about once per month. You might want to go with a cheap pleated filter

 

[MrSquished]

I get four packs of the entry level filters and I have a reminder in my phone to change my HVAC filter once a month.

An air purifier in each major room handles keeping the air clean.

I don't see a point in putting the highest end filters everything HVAC filter it just makes it harder for the HVAC to work.

 

[dullard]

I get four packs of the entry level filters and I have a reminder in my phone to change my HVAC filter once a month.

An air purifier in each major room handles keeping the air clean.

I don't see a point in putting the highest end filters everything HVAC filter it just makes it harder for the HVAC to work.

That is the best method.

 

[RPD]

I built an air cleaner a while back for the litter box room to filter out smells and dust. It's a 3 stage system with dust filter, hepa filter and carbon filter.

Think it's safe to say it was time to change it. At least I know my air cleaner works well.


View attachment 95155

View attachment 95156

Just an FYI you aint getting HEPA filtration outta that.

 

[Red Squirrel]

Just an FYI you aint getting HEPA filtration outta that.

The 2nd filter is merv 13. The seal around the filters is not perfect though so it's not 100% efficient. I built this on a whim when I got my two cats and couldn't seem to control the litter box smell. This actually helps quite a bit surprisingly. The 3rd filter is carbon.

 

[MrSquished]

The best litter for cats is the Breeze litter system with the pee pads. I can't believe I didn't find it earlier, but luckily my friend introduced me to it. It's by far the best of anything I've used and worth it.

 

[RPD]

The 2nd filter is merv 13. The seal around the filters is not perfect though so it's not 100% efficient. I built this on a whim when I got my two cats and couldn't seem to control the litter box smell. This actually helps quite a bit surprisingly. The 3rd filter is carbon.

The only reason it's helping with the smell is due to the carbon filter. HEPA is term that gets throw around in the residential segment as here is a "HEPA" filter, however to get HEPA filtration, you need a HEPA rated housing/rack otherwise the air just mostly bypasses the "HEPA" filter.

 

[Red Squirrel]

The 2 filters are mostly to make the carbon one last longer, that's their main purpose. It seems to be working. But also built this with the idea that it could help during forest fire season if we get lot of smoke. Last year had a few days where it was bad, but it only lasted a few days.

Since the system works on principle of suction most of the air still ends up through the filter as the filter sides push against each other and the final one pulls against the housing. It's not perfect of course but it's good enough outside of any "official" certification. If I wanted to improve it I could probably add some sort of door seal material around the edges of the housing where the filter sits against.

 

[RPD]

The 2 filters are mostly to make the carbon one last longer, that's their main purpose. It seems to be working. But also built this with the idea that it could help during forest fire season if we get lot of smoke. Last year had a few days where it was bad, but it only lasted a few days.

Since the system works on principle of suction most of the air still ends up through the filter as the filter sides push against each other and the final one pulls against the housing. It's not perfect of course but it's good enough outside of any "official" certification. If I wanted to improve it I could probably add some sort of door seal material around the edges of the housing where the filter sits against.

In regards to odors, they don't extend the life of the carbon filter. You wouldn't notice any difference if you ditched the expensive HEPA filter and used another MERV13 or 14 filter.

 

[WilliamM2]

I don't see a point in putting the highest end filters everything HVAC filter it just makes it harder for the HVAC to work.

Try a 5" filter housing. Far more surface area, and does not increase static pressure. Entry level filters don't protect the equipment as well.

https://www.supplyhouse.com/Trion-455602-025-20-X-25-X-5-Air-Bear-Supreme-2000

 

[dullard]

Try a 5" filter housing. Far more surface area, and does not increase static pressure. Entry level filters don't protect the equipment as well.

https://www.supplyhouse.com/Trion-455602-025-20-X-25-X-5-Air-Bear-Supreme-2000

5" filters are good, but often can't be added without major expenses. I know that I'd need my whole HVAC disassembled and reassembled to use one. The cheap 1" filters are good enough to protect the equipment. If you need HEPA filtration, separate HEPA filters spaced throughout the living area is much more effective* at getting you that filtration you need than a single 5" filter in one location, even if it is centralized on the HVAC.

* Imagine if someone closed a vent or accidentally blocked a return in a bedroom that has only one vent (such as dropped a blanket from the bed blocking the return). Any particles generated in that room will take quite a long time to get filtered out with an HVAC filter due to low airflow to that room. A dedicated HEPA filter there will clear the problem far, far faster.

 

[WilliamM2]

5" filters are good, but often can't be added without major expenses. I know that I'd need my whole HVAC disassembled and reassembled to use one. The cheap 1" filters are good enough to protect the equipment. If you need HEPA filtration, separate HEPA filters spaced throughout the living area is much more effective* at getting you that filtration you need than a single 5" filter in one location, even if it is centralized on the HVAC.

* Imagine if someone closed a vent or accidentally blocked a return in a bedroom that has only one vent (such as dropped a blanket from the bed blocking the return). Any particles generated in that room will take quite a long time to get filtered out with an HVAC filter due to low airflow to that room. A dedicated HEPA filter there will clear the problem far, far faster.

They just adjust the duct feeding the furnace, had mine done 2 furnaces ago back in 1993. It's a metal box and will last forever. They do make another option for a retrofit, replaces the elbow that goes into the furnace:

https://www.filtersfast.com/p-trion-air-right-angle-filter-cleaner-m11.asp?kpid=447380-510&fsrc=G3F7G&ffs=gshp&srsltid=AfmBOorEJOfg9zkmnuT_HBjh1S3mZXDzkDqtnPea4QvERjma-1mktqONnCI

I like HEPA filters, but this is to protect the equipment. When they replaced the furnace at 22 years old, the blower wheel and coils were still spotless. 2 filter changes a year, probably overkill.

 

[Red Squirrel]

Just watch you don't restrict the flow to the hvac too much. Typically they are only meant to take dust filters. The goal is to filter out the bigger stuff to protect the hvac and not necessarily clean the air. Although with a proper filter box setup that accepts 2 filters to maximize area you could get away with using higher end filters.

 

[bbhaag]

I get four packs of the entry level filters and I have a reminder in my phone to change my HVAC filter once a month.

An air purifier in each major room handles keeping the air clean.

I don't see a point in putting the highest end filters everything HVAC filter it just makes it harder for the HVAC to work.

I do the same thing but only change them once every quarter. I change every filter in the house at the same time. HVAC, the whole house water filter, fridge filters, etcetera.

 

[Charmonium]

Just a note about carbon filters - re-gassing. All of the microscopic pits and crevices can't tarp molecules forever. So at some point, they start to leach back into the air. Only a big deal if you're worried about odorless, toxic gasses

 

[highland145]

Friend lives in San Fran. Air quality is poor, at times, and he was concerned about what his kids were breathing in at home. He got an air quality tester, a 16 merv filter, 20x20 box fan. Tested the air moving through the fan before and after duct taping the filter to the fan. And, imaging that, the quality was significantly better. As I've gotten older, pollen allergies have gotten worse. I'm in my office 10hrs+ a day with peeps coming in and out. 20'x18' front office space. Tried his rigged up filter a couple of years ago and my symptoms are significantly less. A bit pricey filter but better that a sinus infection-- -> upper respiratory..... put a cheap 30 day filter on top for the bigger particles.

Amazon.com

 

[WilliamM2]

Just watch you don't restrict the flow to the hvac too much. Typically they are only meant to take dust filters. The goal is to filter out the bigger stuff to protect the hvac and not necessarily clean the air. Although with a proper filter box setup that accepts 2 filters to maximize area you could get away with using higher end filters.

Are you referring to my post? It's a single 5" filter.
Two 1 inch filters will not help airflow, it will restrict it even further, never double up filters on HVAC equipment.

 

[Red Squirrel]

Are you referring to my post? It's a single 5" filter.
Two 1 inch filters will not help airflow, it will restrict it even further, never double up filters on HVAC equipment.

Just speaking more in general. The thickness of the filter is not so much the issue, it's the surface area. By adding 2 restrictive filters in parallel it would increase surface area making it less restrictive. Either way, both of these solutions would require modifying the air intake duct quite a bit to adapt it. The big units at my old work place had a big slider and they took like 12 filters.

 

[WilliamM2]

Just speaking more in general. The thickness of the filter is not so much the issue, it's the surface area.

The pleats on a 5" filter gives it far more surface area than a 1" filter. That's the whole idea of a wider filter box.

By adding 2 restrictive filters in parallel it would increase surface area making it less restrictive

That would make it TWICE as restrictive.