I’ve been considering getting a dehumidifier for my residence because humidity is a thing where I live and it might be cheaper to run a dehumidifier than an AC. I’m not entirely convinced this is the way to go, but as part of my research I’ve been pricing units.
I’ve noticed that dehumidifiers cost more than air conditioners. What?
Is there a reason for this? And it’s not just a “start of summer” promotion, this state of affairs also prevailed in February.
So… Why Do Dehumidifiers Cost More Than Air Conditioners?
I do not have an answer. I will just add to being interested in the answer.
I thought dehumidifiers were invented to help printing shops work back in the early 20th century.
The side effect was it cooled the place and voila…air cooling was invented. It also de-humidified the place (because cooler air is less humid than warmer air).
Electricity made development of effective units possible. In 1901, American inventor Willis H. Carrier built what is considered the first modern electrical air conditioning unit.[21][22][23][24] In 1902, he installed his first air-conditioning system, in the Sackett-Wilhelms Lithographing & Publishing Company in Brooklyn, New York;[25] his invention controlled both the temperature and humidity, which helped maintain consistent paper dimensions and ink alignment at the printing plant. - SOURCE
So, basically, it would seem a dehumidifier is an air conditioning unit.
An Air Conditioner moves heat from inside to outside. As part of the process it dehumidifies. The evaporator is cool or cold and moisture condenses in the surface.
A dehumidifier uses the same process, but the heat is not removed from the space being dehumidified. In fact, due to the inefficiency of the system it will actually get a little warmer.
One reason might be that there is a smaller market for dehumidifiers, which would mean there is less competition and efficiency of scale. Compared to AC sales, sales of dehumidifiers would be just a tiny percentage of that. From a mechanical standpoint, I would think a dehumidifier would be simpler and cheaper to build. It is a single unit with no need to vent heat outside. ACs need to dump the heat outside, which means it would be more complicated to design and build. But it since so many more ACs are built and sold, companies can invest a lot to create factories to build the cheapest ACs as possible. But with the smaller market of dehumidifiers, they don’t invest in that efficiency since the market is so small it’s not worth it.
You may be able to get a cheap dehumidifier on secondary markets like Craigslist, Facebook Marketplace, Goodwill, ebay, etc. I got one myself like that on CL. Sometimes people get them for a single use (like after a water leak) and don’t need them after that. You may also be able to rent one from a tool rental or flood remediation company.
Dehumidifiers seem simpler, but they’re really not. They need more sound insulation because all the noisy bits are inside. A window (or wall) air conditioner puts the compressor and blower motor outside, and a sheet of foam and/or plastic separates that from the inside. Most (all?) dehumidifiers also need a tank to store the water with a float to shut it off when the tank is full. Some even have pumps for if you have a drain but it’s at a higher elevation, like a utility sink. They also have wheels, and somewhat nicer materials on all sides rather than stamped metal on the outside. Plus the smaller market as @filmore said. Wall air conditioners are also notoriously expensive despite the fact that they have no shroud. The wall sleeve is separate and usually part of the building. Those do tend to be higher capacity too though, usually requiring 208 or 240v power, so there’s that, but it’s definitely a captive market.
They don’t live half outdoors like window air conditioners but they are still built way better and last much longer. They don’t have a big fan, they don’t have to have a fan at all. I’d say dehumidifiers provide much more value for the dollar. So @filmore makes sense that it’s about the size of the market and the pricing demands placed on window ACs meant to be sold in much higher volume. Currently many window ACs now have a dehumidify mode so in that sense dehumidifiers don’t cost more then ACs, but if you only need a dehumidifier you’ll get a better deal in the long run buying one that isn’t an AC also.
But they do not operate like a dehumidifier. All the dehumidify mode does is shut off the recirculating fan when the compressor turns off. The fan comes back on every 5 minutes for a brief time to check to see if the room is hot enough for the compressor to run. This way the condensation that remains in the unit does not go back into the room. like it does when the re-circulation fan runs all the time.
That’s right, they don’t function the same way. ACs generally dehumidify a room but it’s not their primary function. Also, ACs aren’t a practical alternative for many locations where a dehumidifier is needed, such as basements. I was just putting an additional ironic twist on the question. However, it is a good question since they have the same major cooling component yet window ACs also have a fan, must be weatherized, require a more complex controller, and will come with a number of additional parts for mounting it and sealing the window opening.
The “dehumidify mode” or “dry” mode in a window A/C will sometimes also drop the temperature below the setpoint to try to get the humidity down to where it’s wanted. That’s not good in a basement where it’s likely already too cold. A dehumidifier however will actually warm the air a bit, both by converting the latent heat of the water vapor to sensible heat, and also by dumping the excess heat from the compressor motor and fan motor into the room.
In an alternate timeline maybe, but no. I’ve always been fascinated by HVAC, even since I was a kid, but my profession is architecture (primarily custom single-family residential). There’s some synergies between the two from time to time, but not that often. I have played the role of pseudo facilities manager at most of my jobs, as well as de facto IT manager, so ask me about Johnson Controls pneumatic thermostats, or Windows Server domain and group policy administration, and we can really nerd it up.
We have a nice dehumidifier, but it significantly heats the basement.
It’s the culmination of a series of dehumidifiers. The killer feature of this one is that it can pump the water out the basement window, so we don’t currently have to empty the bucket.