New home high humidity issues

4 years ago

last modified: 4 years ago

I am having humidity issues in my house, humidity levels are not going down below 68% which is very high and due to which we are having mold issues.
Mine is a 4yr old home, 2 storied, energy efficient home, and 5500 heated SQFT. An AC technican was at my place to check the issue and he said my HVAC unit is small for my home.
I have two units one for each story and they are carrier indoor unit model FB4CNP042 and outdoor unit model CH14NB042 and when the technician mentioned that these are small for my home and potentially not holding up the humidity levels I checked with my neighbors (at least 9 exact same model homes) and and they have carrier Indoor unit model FB4CNP048 and Outdoor unit model CH14NB042-A. So we figured my indoor unit if different and small low performance from rest of all the houses in my community. When we reached out the company who installed these units in our home, they said they probably installed this indoor unit for us due to a back order issue and they said it should not make any difference in the performance anyway. However, we believe there is a reason why they installed that combination of indoor and outdoor units in all other houses for better performance and they messed up mine and hence its not maintaining cooling and humidity levels. Could someone please advise if this combination of Indoor and outdoor units I have is not enough for my home and hence humidity issues?

My Indoor Unit is 3.5 Ton. My outdoor Unit is 3.5 Ton
My Neighbors Indoor Unit is 4.0 Ton and their outdoor unit is 3.5 Ton

The AC company guy is saying Indoor unit capacity should match with outdoor unit or it can be higher. Others having a bigger indoor unit doesn't make any difference in this case?
Am not a technician, whatever the AC company guy saying is right?

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Comments (3)

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Austin Air Companie
4 years ago
Air conditioning can provide some dehumidification. However, an air conditioner is primarily designed to drop temperature, not dehumidify.

Pairing a larger evaporator coil with a smaller sized condenser is often done to meet the AHRI --- SEER performance rating. It has really nothing to do with dehumidification abilities.

An air conditioner is turned on by temperature and shut off by temperature. Humidity percentages run independent of temperature. Which is another reason that an air conditioner ---especially a single stage ac --(for the most part) is a poor way to try to control humidity within the home.

Dehumidification challenges for high humid climates can be a real challenge in many instances. Part of what you are experiencing maybe due to something you are doing within the home that is contributing to the problem or there may be a deficiency that is drawing humid air in from the outside.

Newer homes built today are much more tighter construction. Which can work for you just as much against you. Outdoor weather related things are harder to get into the structure... but if they somehow find a way in or it's something you or your occupants are doing... it's harder to get it out.

Because an air conditioner is not designed with the task of dehumidification, means that if your home suffers from high humidity you will have to tackle the humidity problem separate from the AC. The AC was designed to drop temperature, that's what it does. It does not control humidity.

Some air conditioners, due to design and how they run are better than others at humidity removal. However, these systems are still controlled and operated by temperature for the most part... not humidity levels in the home.

There is no free lunch when it comes to dehumidification.

I service the Katy, Texas area.
sktn77a
4 years ago
Sadly, several useful responses to you post have been deleted. Don't know what's going on here but it appears we may be wasting out time trying to help folks if our posts are randomly disappearing.
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mike_home
4 years ago
The posts were not deleted. The poster started another posting. Here is the original:

https://www.gardenweb.com/discussions/5753680/new-home-humidity-issues#n=2

New home high humidity issues

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Austin Air Companie

sktn77a

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