Dust Sticks Like Glue to the New Castle Filters

LESLIE: Well, if you want to breathe easy throughout this allergy season, it’s important that your heating-and-cooling system have a filter that can truly catch the dust, the dirt and the pollen that makes its way into our lungs. But most filters need to be replaced every few weeks and too often, people just forget.

TOM: Well, that’s a lot less likely to be a problem with the new Castle filters. These feature a revolutionary, new design that enables them to last a full year and trap 10 times more dust. With us to explain the technology is Scott Oakes. Scott is the director of sales and marketing.

Welcome, Scott.

SCOTT: Hello.

TOM: You guys have an interesting backstory. You didn’t start in the HVAC air-filter business, did you?

SCOTT: No, that’s right. We started in the dirt-bike industry. We’re avid dirt-bike riders and we have been making foam filters for dirt bikes for over 20 years. And we also have a patented, proprietary filter treatment that goes on, that makes the foam super tacky. And we decided that, hey, this would be great to bring into the HVAC market.

TOM: So, that creation of that new type of foam that had the tackiness to it – as I understand it, that is sort of embedded inside the Castle filters. And it turns out that that was a really important ingredient that enabled you to catch more dust without filling up the filter and making it harder for the air to pass through. Is that correct?

SCOTT: That’s exactly right.

So, in the motorcycles and as well as the Castle air filter, the filtering media is this cellular structure that’s made out of foam. And the way that it – to make it work the best is that you cover it with this filter treatment that makes it super sticky and tacky. And so, since it’s all made up of tiny, little cells, it’s the cell walls that get sticky. And when the dirt – the dust and dirt come and hit up against the sticky wall, it adheres to it but the center of the cell remains open so it flows air through. And that’s what makes the filter work so great.

Because the thickness of the foam – it’s ¾-inch in the HVAC filter – it’s able to pack away 10 times more dust than a standard, pleated paper filter and still flows great air.

LESLIE: I mean that’s really amazing that it’s able to tuck away so much that you can have a single filter last a year. I’m guilty of not changing our, you know, traditional filter as often as I’m supposed to. And boy, are they disgusting. So, how gross are these after a year or is it so encased in the foam that you don’t even see it?

SCOTT: Well, that’s not always the case. It does start to pack on the dirt and the dust inside the filter. But over time, it can look a little bit dusty on the outside. But it doesn’t mean that it’s not working. It’s still flowing air that you need and catching dust. And sometimes when people think it’s just too ugly to look at, you can easily just pull it out and just bang it outside on the ground or vacuum it off real quick and install it right back in.

So, you’ve got those options to do for aesthetics. But as far as the functionality of it, even though it might look like it’s packing all the dirt, it still is flowing air just fine.

TOM: Now, when you look at the filtration industry, there’s a lot of different filters out there that are designed for specific purposes or at least they’re marketed that way, right? So some are considered more of an allergen filter, some are aimed at odors and such. Is there more than one type of Castle filter or are they all the same, because you don’t really need to [have it vary] (ph)?

SCOTT: Currently, we’re pretty much the same as far as the filtration goes. Actually, we do have two different models right now. We have what we call our High-Flow filter. Now, that’s our flagship filter. It’s good for about 90 percent of the homes out there. And it’s got our three ¼-inches of foam with the sticky/tacky filter solution on it. And it flows air really great.

But some homes are a little bit under-engineered or are a lot older HVAC units that really need a lot of airflow for it to function well. We do have what we call the Super-Flow. It has a little bit thinner foam on the inside and so it flows way more air. Still works for a whole year but it’s probably – it’s more rated for a MERV 6 for people. If you’re using one of those green, fibrous – what do you call those?

TOM: I call them “rock stoppers.”

SCOTT: Yeah, you’ll stop rocks and twigs and birds and stuff. But if your home needs one of those kind of filters, then our Super-Flow would be great for you. But other than that, we don’t really have a charcoal filter as of yet. We’re kind of young and we have a lot of great ideas of future markets we want to move into. But right now, we’ve currently just got our High-Flow and our Super-Flow.

TOM: Now, I want to clarify. We talked about the fact that this foam is a sticky foam but that’s not what you feel on the outside, right? That’s all encased inside layers of sort of foam. It’s not sticky. Is that correct?

SCOTT: That’s correct. I’m glad you asked that, because the filtering media is made up of three ¼-inch pieces of foam. And the – it is the center one, the one in the middle, that’s got that – the tacky surface on it. And the outside two pieces of foam are completely dry. And so if you happen to touch it with your fingers or anything while you’re installing it, you’re not going to get any sticky solution on your hands at all.

LESLIE: So, Scott, because we’re just using one per year, I imagine that the Castle filters might be a little bit more expensive. But how does that compare when you’re thinking of a year’s worth of the more common rock-stopper filters that are out there?

SCOTT: You know, you’re right. The Castle filters, they’re going to range, retail-wise, between $24 and $32, $34 – $24 and $34. And it is a little bit higher than some of the pleated filters you can get in Home Depot.

But the thing you have to remember is – usually, we found that the pleated filters, they are going to fail when they get about 5 to 15 grams of dust on it. And a normal household of about 18,000 square feet is going to gather about a gram a week of dust. So, in about every 4 to 6 weeks, you have to change out one of those pleated paper filters and that’s going to cost you. And if you do it regularly, at the right time throughout the year, that could be up to eight changes. And so there is some – if you leave ours in for the whole year, there is a little bit of savings there.

But the biggest savings is going to be lower energy costs. Because even though it captures a lot of dirt, it’s still flowing really great air. And your static pressures are going to remain low which means, over the course of a year, your air conditioner or your furnace won’t have to run as long to heat or cool your house because it’s flowing really great air.

TOM: When I say that I’m glad there are guys like you that can calculate exactly how many grams of dust we accumulate every month, I mean that’s good information to know.

SCOTT: Yeah. I’ve just got all kinds of little dust traps around the house and I just check it out every – no, it’s a calculation. And then there’s some stats out there and …

TOM: I’m sure. I’m just kidding you. Yeah, well, that’s fantastic.

Look, I was a home inspector for 20 years. I can’t tell you how many times I opened up blower compartments of either furnaces or just air-conditioning air handlers and just found filters that were completely forgotten, absolutely, totally caked and super ineffective for the job that they should be doing.

And as a result, especially when it comes to air conditioners, those coils would get clogged up inside those systems. And boy, when that happens, you can blow a compressor and it becomes very, very expensive. So, you’ve got to have the right kind of filtration. This a real advance in what we’ve seen out there.

Scott Oakes, thank you so much for sharing this info with us.

Scott Oakes is the director of sales and marketing with Castle Filters. You can learn more at CastleFilters.com. That’s CastleFilters.com.

Thanks, Scott.

SCOTT: Thank you very much.