It’s time for my filter to be replaced…I’m not quite sure how to decide which to buy. Any tips?
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I am not sure what is the best filter to use either. Need some help on this.
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Hey Tommy! I’ve just been through this as well. It seems like the higher the “merv” rating, the better? Though I’ve read online that sometimes it helps to talk to your HVAC pro to see if your air handler can handle the filter rating. Last time I had my air handler serviced, they put in a 1" merv13 filter which has been great. Saw a visible decrease in particles. The app says I need to replace my filter in 2 weeks so I’ll probably buy one with the same rating.
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I live in a condo, and they sell filters to the tenants. I don’t think they’re good quality though, since I could vacuum it and it looked clean! So I did some research and it looks like they’re making money out of thin air. From what I found MERV-8 filter is kind of the minimum rating you should go for. But what is also important is that you should install it properly - if there are gaps - the air will just go around it. It seems obvious, but I never thought about it before.
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Just building on this - the higher the MERV rating, the smaller the particles will be caught. Talking to your HVAC pro is a good call because not all systems can handle filters with high MERV ratings. It can make your system work way harder than it needs to, resulting in a lot of unnecessary energy consumption. It can also make it so that you need to replace filters way more frequently than need be. I learned this the hard way…
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I’ve heard this about MERV 8 as well, that it’s the safest bet when it comes to system compatibility.
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I normally just leave the work to my HVAC pros and trust him with the filter and when to replace it. I probably need to research more on this. The comments in here is really helpful though. Thank you folks.
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My hubby buys the filter and installs it himself. He thinks it’s not the best one but it’s not the worst one either.
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I’m not sure what you mean by compatibility, I thought they’re standard size?
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Oh dang, big repair?
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Yeah, I think once you figure out what your system can handle, it’s easy to go to the store and just buy something with the same rating. Probably cheaper to do it this way if you don’t need any other HVAC maintenance at the time of replacement.
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We…don’t have a dedicated HVAC person 
How did you find yours?
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i dont know if my system can handle something like what your describing above. how do you figure this out without getting an hvac technician to come out?
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Choosing a filter is not always the easiest process, but allow me to try and assist in the direction. Many of you likely have 1" thick filters. i say this because most people using larger, thicker filters know already what filters they should use.
Ok, so for 1" filters specifically, it is difficult for a few reasons. The first is that you will be wanting to use a filter that provides high filtration while offering low resistance to airflow. This is not possible without weaving/manufacturing a very tight fabric. In doing so, we inherently cause a large pressure drop even with clean filters. Many 1" filters suggest up to 3months of use. This is not going to be good on an air-cooled motor or heat-exchanger. and if these parts can’t exchange temperature well, neither can your body and the room around you. You and your HVAC system will suffer.
So to wind this up, in many cases, when dealing with a 1" filter, the answer is to actually use stages of filtration. Start with a medium grade filter, and then add by-pass filtration (post-filter) to manage the smaller particles. Further to that you can the add UV or Ionizing air purification (post-bypass filter) to further sterilize the air if needed or desired.
However (and this is a big one) usually when I see 1" filters, the duct design and installation has been done in the lowest cost manner and therefore, there is little room for additional components and/or filters.
Hope this helps!
p.s. Staging of filtration is the best for all systems and families, big or small!!
p.p.s. By using bypass filtration, you can clean the air without affecting the pressure drop across the HVAC system. Also, bypass filtration can be HEPA or non-HEPA. Some bypass air cleaners can clean up to 2/3 of the air passing it. Based on the air changes per hour of your system compared to the air changes per hour ability of the bypass unit, you may be able to clean the entire volume of your home’s air in under 30mins using bypass filtration and a medium-grade 1" main filter
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Wow - a lot more complicated than I expected! Thanks for the help @CustomVac!
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