I disagree. Whether the air entering the cabin makes a single pass in normal operation or multiple passes when in recirculation mode, it's still being filtered. The degree of that filtration depends on the quality of the filter. In theory, a vehicle with a HEPA filter sitting still with the HVAC system on recirculation mode could achieve near-perfect air quality. Obviously, that's not possible in the real world, but the idea that the filter is there just to protect the HVAC system is flawed. Why do you think so many cabin filters are sold with activated charcoal? Do HVAC systems have a sense of smell? The filter is there to improve air quality in the cabin for the passengers, the fact that the blower is also located in the cabin means it also benefits from the filtration, but the system is primarily designed for passenger comfort.
CX-5 Cabin air filter on Amazon?
- Thread starter Carfo
- Start date
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- 2016.5 CX-5 GT AWD titanium/black 2016 Miata Club ST MT white
If the above were true, then why-o-why is the cabin filter in the Miata nearly impossible to change? A good portion of the dash needs to be opened up to change the MX filter.
cabin air filter location ? - MX-5 Miata Forum
cabin air filter location ? ND Maintenance
forum.miata.net
As for the charcoal? While it does help with odors how long do you think it lasts before the charcoal no longer absorbs odors? Not long in my opinion.
Then why do they add charcoal? Marketing. That said, I did buy the filter with charcoal added.
I haven't noticed any reduction in odors with the charcoal, can still smell that garbage truck in front of me, diesel fumes still make it inside.If the above were true, then why-o-why is the cabin filter in the Miata nearly impossible to change? A good portion of the dash needs to be opened up to change the MX filter.
cabin air filter location ? - MX-5 Miata Forum
cabin air filter location ? ND Maintenance
As for the charcoal? While it does help with odors how long do you think it lasts before the charcoal no longer absorbs odors? Not long in my opinion.
Then why do they add charcoal? Marketing. That said, I did buy the filter with charcoal added.
Also, these filters can be washed, it's tough material on the original filter.
The hepa filter I had just didn't allow enough air flow, especially on a hot summer day when you have the blower on full speed to get cool air inside.
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- 2016.5 CX-5 GT AWD titanium/black 2016 Miata Club ST MT white
Which filters can be washed? The charcoal filters? Washing charcoal isn't going to do anything.
With a Miata, you have a small car packed with all the same features of larger vehicles. The engineers have only so much room to work with so concessions must be made. I have a '59 MGA, which is about the same size as a Miata, and it's easy to get to all the components because it doesn't have many. I'm actually surprised most cabin filters are so easy to change. As a routine maintenance item, if owners had to struggle with it people would be more inclined to just have the dealer do the work. Low hanging fruit for the service department.
The filter manufacturers suggest that ones with activated charcoal last about six months. There's a huge variable with that time frame due to how much use each individual filter gets. I suspect most people won't think about changing the filter that often, and as Conrad noted, they can't be washed and reused. Once the microscopic pores in the charcoal are contaminated, the filter's ability to eliminate odors is done. The only way to reactivate charcoal is with high pressure steam, not something you can do yourself, and not worth the bother since filters are inexpensive. For my use, I didn't bother with a charcoal filter because of the relatively short life cycle.
The filter manufacturers suggest that ones with activated charcoal last about six months. There's a huge variable with that time frame due to how much use each individual filter gets. I suspect most people won't think about changing the filter that often, and as Conrad noted, they can't be washed and reused. Once the microscopic pores in the charcoal are contaminated, the filter's ability to eliminate odors is done. The only way to reactivate charcoal is with high pressure steam, not something you can do yourself, and not worth the bother since filters are inexpensive. For my use, I didn't bother with a charcoal filter because of the relatively short life cycle.
The original ones that came with the vehicle. I'm not suggesting you wash an aftermarket, I'm not even suggesting you buy a charcoal one.
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- 2016.5 CX-5 GT AWD titanium/black 2016 Miata Club ST MT white
I see your point and stand corrected on the MX.
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- Toronto
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- 2022 CX-5 GT
The Miata is a convertible though, in that case I’m pretty sure the only goal of the filter is to protect the HVAC system.If the above were true, then why-o-why is the cabin filter in the Miata nearly impossible to change? A good portion of the dash needs to be opened up to change the MX filter.
cabin air filter location ? - MX-5 Miata Forum
cabin air filter location ? ND Maintenance
As for the charcoal? While it does help with odors how long do you think it lasts before the charcoal no longer absorbs odors? Not long in my opinion.
Then why do they add charcoal? Marketing. That said, I did buy the filter with charcoal added.
About the HEPA filter, some people are really sensitive to dust and fine particles. And yes our cars aren’t fully sealed but we sometimes have to drive through construction sites and stuff and I assume some people want to minimize their exposure.
I went for the charcoal too as it was pretty much the same price as a regular one. Charcoal or not, what I do care about is the filtration efficiency.
Cabin Air Filter - BASIC vs ADVANCED vs PREMIUM - Which is the best?
Hi guys! Today we'll compare tree cabin air filters from Mann. The basic one vs the advanced one vs the premium FreciousPlus. Let's see if there's any differ...
youtu.be
This is by far the most detailed filter efficiency video I have seen. From what I see, there are small (negligible or not, your call) differences between different types of filters.
What I am more concerned about is whether a no-name filter does any filtration at all. I initially wanted to order a Mann/Filtron filter but they don’t seem to be available in North America. I asked my brother to buy me a couple (they cost around €8 in Europe) and bring them whenever he visits me.
Some of us want to cut down on cost while getting the same(?) filtration efficiency. Some of us want to increase the filtration efficiency without paying more. So I see the point of the Bosch HEPA filter, and I also understand that it’s not for most of us.
Since it's been mentioned a couple of times, I have a question about the idea of protecting the HVAC system. What exactly needs protecting? If it's just a matter of keeping leaves and dirt out of the vents, wouldn't it make more sense to just run a "T" off of the intake duct downstream from the engine's main air filter, rather than installing a completely separate system? Engineering 101 is to build as many features into a car as cheaply as possible and such a system, particularly in a Miata, would reduce costs and free up needed space. An engine's air filter is capable of protecting internal engine components that are machined within thousandths of an inch, so it should be able to do the same for a HVAC blower manufactured with much looser tolerances. I guess Mazda knows there are some buyers that will NEVER drive their convertibles with the top down and gives them all the features they expect in a sedan/suv.
And mrplt, you are correct, I happen to be one of those sensitive people. Blessed with tons of airborn allergies plus asthma, the air around me can never be clean enough.
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- Toronto
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- 2022 CX-5 GT
Absolutely, Engineering is basically that, but you want those features to last as well. It’s about balancing features, cost and reliability.
It is possible that designing and manufacturing that “T” is more expensive than using the components that are already designed and tested.
I personally don't have any proof, but it makes no sense to me about "protecting the HVAC system" as these filters were not a thing until fairly recently. I know my 80's VW's and Mazda's didn't have a filter. I don't think my NB Miata did either. I think they are to reduce dust/particulates in the interior. Some are certainly better than others to replace.
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- Plano, Texas, USA
Just about to say the same. Of course YMMV.
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- Plano, Texas, USA
“Protecting” the HVAC system means this cabin filter mainly is use to prevent the dirt to get on the AC evaporator and heater core too easy so that they can keep their efficiency much longer. They aren’t like radiator and AC condenser which can be cleaned easily.
The side benefit of the cabin filter is to clean the air a bit we breath inside of the car as long as you don’t open the door and keep all windows shut.
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- 2016.5 CX-5 GT AWD titanium/black 2016 Miata Club ST MT white
Say what?
What needs protecting? Do you understand how a HVAC system works and what a heat exchanger is? Look at your car's radiator, that's a heat exchanger. See all the fins? Imagine if all the fins were caked with dust and/or debris. How much air will flow and how much heat will be exchanged?
Please tell me that you're not seriously suggesting that the HVAC and the engine share the same filter? This would free up needed space?
So, some big ole duct, T'ed off of the intake and passing through the firewall would free up space?
There's a reason why absolutely NO manufacturers have done this. Actually, MANY reasons. Not the least of which is the possibility of sucking underhood air into the cabin.
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- 2016.5 CX-5 GT AWD titanium/black 2016 Miata Club ST MT white
LOTS of stuff didn't become a 'thing' until someone thought of it and decided that it was a good idea.
When we bought our home years ago the previous owners decided that they didn't really need filters in the HVAC system. I don't know how many years it was operated that way but the heat exchanger was caked with dust and the air flow was VERY much restricted. It was a mess, and it took me quite some time to get the crap off of the fins and open the system back up.
What do you think the chances are of the heat exchanger in your car getting caked with crap if there wasn't a filter in the system?
I'll admit I haven't studied the Mazda HVAC system, but I recently upgraded my '89 Suburban's a/c to a Sanden compressor, along with replacing all of the associated components, so I've done more hands-on work with air conditioning than most.Say what?
What needs protecting? Do you understand how a HVAC system works and what a heat exchanger is? Look at your car's radiator, that's a heat exchanger. See all the fins? Imagine if all the fins were caked with dust and/or debris. How much air will flow and how much heat will be exchanged?
Please tell me that you're not seriously suggesting that the HVAC and the engine share the same filter? This would free up needed space?
So, some big ole duct, T'ed off of the intake and passing through the firewall would free up space?
There's a reason why absolutely NO manufacturers have done this. Actually, MANY reasons. Not the least of which is the possibility of sucking underhood air into the cabin.
People keep saying the cabin air filter protects the HVAC system. Are you saying the cabin filter located behind the glovebox keeps leaves off the condenser? (It's called a condenser, not a heat exchanger.) Please explain to me how air entering the front grill, where the condenser is located, first flows through the filter behind your glovebox.
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- Plano, Texas, USA
Single-purpose / dedicated vs. all-purpose / multiple-purpose ⋯Say what?
What needs protecting? Do you understand how a HVAC system works and what a heat exchanger is? Look at your car's radiator, that's a heat exchanger. See all the fins? Imagine if all the fins were caked with dust and/or debris. How much air will flow and how much heat will be exchanged?
Please tell me that you're not seriously suggesting that the HVAC and the engine share the same filter? This would free up needed space?
So, some big ole duct, T'ed off of the intake and passing through the firewall would free up space?
There's a reason why absolutely NO manufacturers have done this. Actually, MANY reasons. Not the least of which is the possibility of sucking underhood air into the cabin.
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- Plano, Texas, USA
Sorry, for AC it isn’t the “condenser” in the HVAC system inside of dash, it’s the “evaporator”. So as the heater core is in there. Both can be considered as a “heat exchanger” but for totally different purpose. The cabin air filter mainly is to protect these 2 components from dust and debris keeping these clean for their efficiency.
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- 2016.5 CX-5 GT AWD titanium/black 2016 Miata Club ST MT white
Where do you think that the cold comes from inside the car for the AC?
Basically, the compressor under the hood compresses the freon, compressing the freon creates heat, the condenser (which is a heat exchanger) in front of the radiator removes this heat. The cooled freon then flows into the cabin and expands inside another heat exchanger (evaporator). When a compressed fluid expands it absorbs heat (gets cold) and the air flowing through this heat exchanger is then cooled off and flows into the cabin to cool you off. If that heat exchanger is caked with dust, you'll have restricted air flow. If the condenser (in front of the rad) is caked with bugs, or whatever, you'll still have airflow inside the cabin but it's not going to get as cold as it should.
