Which AC system is best for Bronchiectasis & MAC?

@jill6063 That's an interesting question for December 30th - maybe you live somewhere warm?

Central air conditioning, if hooked into the ductwork system in your home is a better option because you can place filters in the ducts to help control dust and particulates in the house. Two caveats - the moisture removed must be directed outside or directly into a drain and the filters must be changed OFTEN - usually even more often than recommended - but filters can easily be bought in quantity to keep the price down and this is an easy do-it-yourself task.

Window air conditioners also have filters, but they are tiny by comparison and require attention as often as weekly during the cooling season.

Thank you so much, Sue! We just bought a house on the Jersey shore and I’m thinking ahead! We just had the furnace replaced and the guy said it would be very easy to add central air so we were considering it. I personally don’t like to use AC except when it’s blistering hot. I imagine it would also be wise to use it on poor air quality days, which we experience in NJ more often than desired.

Thank you, as always, Sue, for your generous guidance!

Kind regards,
Jill

This is a timely question for me, Jill. I have a central AC on my roof that's working pretty much 24/7 much of the summer here in the desert. A technician stopped by in August to do our semi-annual inspection of the system and noticed I was doing a breathing treatment with my Aerobica and saline. He commented that his wife is a respiratory therapist and we got to discussing AC systems and respiratory problems. Beyond changing the filters often, he also said that lots of organisms grow on the moist surfaces of the interior of the machine. When he went up to inspect he took some photos of the fan and the other parts of the system. Yuck---covered in biofilm and gunk. He thoroughly cleaned the inside of the unit and subsequently installed a UV light to kill the organisms. My ID doc concurred that UV light kills MAC. I now suspect that I might have gotten MAC from the AC unit. Of course, NTM is everywhere so it's impossible to avoid completely. We can only do what we can to minimize more exposure.

Grrr! I have been wondering the same about the ancient rooftop unit in our tiny mobile home! Our tech is really good at keeping it clean and operating, probably not very efficiently. But at 31 years we have been discussing replacement. I guess that moves to the top of the list for 2025 purchases. Now to decide between an add-on to our ducted furnace or two mini-splits (combined AC/heat units) for the front and back walls.

In my own experience, I have found that my central heating and air conditioning have better filters and air returns. I also have a lanais with a window unit. Three things with the window unit…1) The air filter is useless against stopping particles from entering my home and 2) I can see daylight through it which brings me to 3) It does nothing at all to stop allergens such as ragweed and pollen.

In our old house we have large radiators and window AC units. We've looked at mini splits but indecisive hubby is still deciding. The way I cope with the faulty filtering of the window units is to run 2 air purifiers in the bedroom. Their pre-filters get vacuumed every 2 weeks and 1x year HEPA filter change. Since their installation I notice a lot less dust.

It's been challenging to determine how effective the mini splits are at filtering. And if they might trap things like NTM in a good or bad way. Thus the indecision.

So - in my learning about mini-splits, they have very rudimentary filters, and like window units these are often mesh or screen which you wash with water. This makes a mini-split much less attractive to me as I would need to climb a ladder to get to the filter. I live in a dusty area, so this would be every 2-3 weeks. To ignore filter cleaning would quickly affect their efficiency and power use. And I would still need to run my HEPA filters.

Here is just one analysis I found, but most other unbiased reviews seem to agree:
https://aircondlounge.com/do-mini-splits-have-filters-to-clean-the-air/

We too have an old house (built in 1929), heated with a gas boiler and radiators so it is an enclosed system. A few years back, we had ducted A/C installed in the first floor and split units upstairs, and I can emphatically say it was the best home improvement decision we ever made. The central A/C filter doesn't get very dirty at all (no pets!), but the technician comes once a year and changes it as part of his cleaning routine. The split unit filters are quick and easy to remove and clean and we do that ourselves.

While we used the A/C more than usual this past summer, we generally use it only during heat waves since our night temperatures are cool. But in 2023 we experienced the effects of the Canadian wildfires, and being able to keep our windows closed 24/7 was a godsend; we never even had a whiff of smoke in our house.

Perhaps the split units wouldn't work as well if they were run for weeks on end, but here in upstate New York they are an excellent solution for dealing with shorter periods of heat or poor air quality. I would highly recommend them.

Thanks @tcd518 this is great to hear from first hand experience. Your post has me wondering a few things.

How did they duct your first floor? From basement with floor returns? And for the mini splits you say you clean and maintain the filters yourselves, what's involved with that? Do you also use a heat pump? And lastly since you're so pleased with the minis what brand of compressor was installed? Thanks in advance for your answers.

Jill
My sister, Jill, is in Belmar. Many years ago our Mother did have central air installed. In the big picture, from what I understand, Jill doesn't have to use it that often. However she is a 1/4 of a block away from the ocean breeze. The reality is the central AC is really nice because you have cool air in all areas of the cooled interior of the home rather than multiple window units or just one or two window units and then you go from one cooled room to a hot room. I'm sure you have thought of that.
I think with all the posts on this thread we have a great deal to digest and think about.
Happy 2025.
Barbara