The blog formerly known as   Fake Plastic Fish

March 12, 2008

Hi, there. I want to talk to you about ducts.

This post has only the loosest relevance to plastic. Some ducts are made from plastic. And they would get very dusty if not for the plastic filters which catch much of the particulate before it enters the furnace. Of course, I didn’t know any of this before I read Burbanmom’s post a month ago about how we should be changing or cleaning our furnace filters monthly in order to help our heating systems work more efficiently and save energy.

My first reaction was, “Furnace filter? I didn’t even know we had a furnace, much less a filter to clean. We are renters. We program a little box on the wall to turn the heat up to 65F when we’re home and down to 60F when we’re out or asleep, as per Crunchy Chicken’s Freeze Yer Buns Challenge. Hot air magically comes out of vents in the ceiling. You mean, there’s more to it than that?” So I Googled “change furnace filter” and found many photos like the one to the left. We must have a furnace somewhere, and according to the photo, the filter is pretty easy to change, right?

I am nothing if not curious, like the kitties, and thrifty, so I decided that if changing/cleaning furnace filters would help me save energy and money, as Soots is my witness, I’ll find out where that furnace is and change or clean the filter! I had noticed this big vent in the livingroom wall. Just figured it was another magical place that heat came out. Could this be where the furnace lives? I unscrewed the screws and looked inside.

Um… No. This is not where the furnace lives. Not to be thwarted so easily, I reached in and up and pulled out this:

Cough. Looks like a filter to me. It’s blue plastic under the thick layers of dust. According to instructions I found online, this is a permanent type of filter that can be cleaned and replaced. That made me happy. Not another piece of plastic waste to add to my weekly tally. I put it in the bathtub and sprayed out most of the dust with the pulsating setting on the handheld shower massage until the water ran clear. It took awhile. I don’t know if that thing had ever been cleaned. And we’re supposed to do this once a month?

So anyway, I left the filter outside over night to dry. The next day, it was ready to put back into the hole. But I still hadn’t found the furnace. Climbing into the wall hole and looking up, I saw this:

A Duct! I knew it was a duct because I’d seen the movie, Brazil. I learn a lot of things from the movies. This duct seemed to lead to the attic. Could the furnace be in the attic? Do they even put furnaces in the attic? I Googled “furnace in the attic” and found that yes, they do indeed install natural gas furnaces in attics sometimes. It was time for yet another adventure! I climbed up into the attic and, making my way through all the crap we have stored up there, found this!

And some more ducts. A lot more in fact. I wondered if there was another filter inside the furnace. You see, all the photos online were like the one showing the woman pulling the filter out of the furnace itself. So I thought maybe my furnace had an extra filter hidden inside somewhere. I opened it up and looked inside.

But there wasn’t anything in there that looked like a filter. I was confused. Then I remembered that my sister’s husband in Maryland is a contractor. He would know the answers. (Of course, my landlord is also a contractor but for some reason I was too embarassed to call and ask him. He’s always in a big hurry.)

So I called Jess in Maryland tonight and he explained what many of you reading this have known all along… that while the hot air comes OUT through the vents in the ceiling, it goes back IN through the big vent in the wall. That vent is an in-take, and the air is filtered BEFORE it goes back into the furnace. So I had found the filter after all, and I had cleaned it properly and put it back.

The thing is, I think I put it back upside down with the fuzzy part facing up because I thought the air came down through that filter rather than up. I’ll have to flip tonight.

Has this post been a bit air-headed, a little long-winded, and perhaps twisted and turned a tad too much? Sorry about that. I could have had a simple furnace filter to find and clean, but how interesting would that have been?

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15 years ago

I am attempting to catch up, I started at the beginning after finding you on Dave’s 365 page..I have been enjoying reading all your posts and I especially enjoyed this one with the photos and story alongside it. I’m a visual person and it’s easier to picture what you are doing when it’s something I’ve never done before :)


15 years ago

WOW – epic filter-cleaning mission! I’ve never seen a heating system like it – I’m used to radiators powered by hot water circulating here in the UK. At least, I hope they don’t have plastic bits that I’m supposed to find and clean!

15 years ago

You are so brave! Crawling around in the attic gives me the willies! I have probably watched too many movies. I do know we have the washable furnace filter. I also know I am not the one to retrieve it when it needs washing!

Shannon Hodgins
15 years ago

Hey, great tip for renters. When I rented I just assumed all that was done for me. We keep a stack of filters by our furnace so we remember to change them out. Shannon

15 years ago

Oh and I meant to add that your furnace and attic looked just like our previous house’s attic and furnace in South Carolina.

Our hot water was also up in the attic ,too. And it always made me so nervous that one night we’d be awakened with showers of water gushing through the ceiling!

15 years ago

I think you should have made a video of your sleuthing and then sped it up!

That would have been a riot watching you running from furnace to computer, from filter to computer, from bathtub to computer, from phone to furnace, and then furnace to filter, and then laying down in exhaustion!


Your blog is informative and funny!

Beth Terry
15 years ago

Some answers to questions:

1) Apparently it is common for natural gas furnaces to be installed in attics in this part of the country. After telling my story at work today, I found that at least two of my co-workers have the same setup. One of them recommended installing a ceiling fan to push the warm air down. But will the savings in gas make up for the electricity used to power the fan? Any ideas?

2) There are only two units in our “building” which is more of a house with a top floor unit (ours) and a bottom floor unit. We also have the attic. I have no idea what kind of furnace the guy downstairs has or where his is located, since he doesn’t have an attic, but I’m sure he has some kinda furnace somewhere!

3) My brother-in-law said that the filter that I found should be the only one. There is not another one in the furnace itself. And in fact, before I called him, I opened up one of the ceiling vents to see if there was a filter in there, and there was not. I took pictures of that, too, but didn’t include it because the post was just getting too long and convoluted.

4) Thanks Christy B for the info about recalled furnaces. Ours is a Sun Dial from the Square D Company and is not listed on the recall page, thank goodness.

5) Thanks, Low Impact, for suggesting we have the whole system properly cleaned. We don’t have A/C is it’s unnecessary in this area where we only have about 5 hot days per year. But I doubt those vents have ever been cleaned out and thanks to you, I’ve been doing more research online and finding there are companies that will come and suck out all the dust from the vents and the furnace fan.

They also say they can fog the cleaned system with anti-microbial stuff to kill bacteria and dust mites. What do you all think of this? Is it beneficial or toxic?

15 years ago

Congrats on finding the filter and furnace–I echo the question–is that the only filter you need for your furnace? There isn’t one for the air coming out? My other question is do all intake vents need a filter? I don’t think I have one on mine…

15 years ago

How many units are there in your building?

You should ask the landlord to clean the vents in all of them. Ick!

We have a boiler, which means no air filter…I think. Our new boiler has an outside air intake. I better look at it.

15 years ago

“BETH’S DUCT: Her Big Search” I rate it five stars! It’s an educational, illustrated, intense and interesting thriller with a happy ending and, best of all, it co-stars Soots, talented and handsome young cat actor. It’s rumored that he and his sister, Arya, will be starring together in the sequel to BETH’S DUCT, “BETH’S STOVE: What Lies Beneath and Behind”. Wait & see.

15 years ago

10,000 blessings upon you for being insatiably curious. This is SOOOOOO rare. Most people seem to be on autopilot and have a complete lack of interest even in what is directly in front of them, like your furnace filter (unless it’s a TV, but even then no interest in how it works). Be like those cats!

Speaking of filters, and I don’t want to frighten anyone, but have you ever checked out the filters in the heat pumps that are commonly used for heating and cooling motel rooms? Just pop the plastic cover off of one the next time you stay in a motel and you will likely see a completely clogged filter just like yours was. I routinely clean these filters before I stay the night as a public service to those who will follow me in the room and as a way to save energy for the unknowing motel owner and all of us.

On furnace filters in general, I had an electrostatic filter in my former house…no filters to replace, so no waste since high voltage electricity pulls the dust to a cage of metal plates that can be easily cleaned in a dishwasher.

heather t
15 years ago

So… was that the only filter, then? There isn’t one on the furnace to filter the air before it comes out the ducts?

Excellent sleuthing, as usual. Love the visuals! Ack on the big wad of dust in the vent!!!

christy b
15 years ago

Warning! There was a recall of horizontal furnaces. Make sure that your’s is not on the list:

What an adventure!!

Central Services
15 years ago

You’ve ‘ad that scab Tuttle ‘ere, ‘aven’t you?

Central Services don’t take kindly to saboteurs!

And yes, we’ve got a 27B/6!

“We do the work, you do the pleasure”

15 years ago

I have 2 small intake vents to my HVAC and one filter at the bottom of the unit. It’s a pain to change since someone didn’t pay attention to the fact that the filter is longer then the space between the unit and the wall. So there is some bending and cussing involved, but we do it once a month (or at least I try to do it). The HVAC will certinally work better when the filter is clean.

Don’t forget to have your furnance/ac check up twice a year. The tech will clean your coils and check for freon leaks. These 2 check ups will save you money in the long run.

15 years ago

I recently switched to a locally made permanent eco filtre for my furnace. I change mine every three heating months, per the recommendations. I also vaccuum out my ducts as often as it strikes me to. I used to have the kind you do, and cleaned it regularly, but when I had a new furnace installed, they put in those dastardly disposable ones, which I used up.

I loved your pictures! As a former property manager, I really appreciate it when people figure out how their home works, instead of just taking it all for granted!

15 years ago

Great…just great…now I’ll have to add that to my list for today.

Mine’s easy. In the basement near the washer and dryer. And I think I have an extra filter.

Thanks :-)

15 years ago

Is it common where you live to have the furnace in the attic? This doesn’t make sense to me, since heat rises. Not that you can do anything about it, since you are renters, but I’ve actually never heard of this.

15 years ago

hello I’m richelle but you can call me rich

here in the philippines we use eco-bags to reduce the use of plastic bags…its already a law so most stores/groceries/boutiques use eco-bags

good luck =) on your mission

check the link ;)

15 years ago

heeellllooooowwwww der…it’s nice to view your blog…ur topic is so interesting…dats ol..hehehe
I’m sorry if dats only my comment bcause I’m not fluent in English….
pls,,,view also my blog
tkecare olways…

15 years ago

Where’s De Niro when you need him, eh?

15 years ago

Wow. I don’t think I’ve ever heard of anyone embarking on such a determined quest to find a furnace filter! Great job, Beth!

Now you can breathe easy, eh? snicker.snicker.

15 years ago

hi there, what a nice blog you have here, ;)

15 years ago

Hey, congrats on sleuthing and climbing and crawling and braving dust mites (oops, hope I didn’t open a new topic), and finally successfully finding your duct. At least you’ll sleep better knowing that you are enjoying cleaner air and saving $$, too!