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[WalterHanson]

Isn’t air conditioning supposed to remove humidity? So why is yours not doing the job?

Your AC unit is too large for the space.
First of all, when we talk about AC size, it’s about cooling capacity, not the physical size of the unit. That’s not the only part that people misunderstand about AC size.

Your AC size needs to be carefully calculated using a load calculation process. If your AC was chosen and installed by a builder rather than a qualified HVAC company, there’s a good chance that it was done incorrectly. That’s how many homes and businesses end up with oversized units that provide poor HVAC humidity control.

Your AC is limited to a single speed

An air conditioner that’s only capable of running at one speed— basically, on or off—can have the same problems as one that’s too large when it comes to HVAC humidity control.

When the unit can only run at one speed, it turns on and runs full blast until the air reaches set temperature. Then it turns off until the temperature once again goes above the thermostat threshold. That often means the unit doesn’t run consistently enough to remove humidity.

Negative air pressure in your space
Negative air pressure is the result of a poorly designed ventilation system. In a nutshell, it means that you are venting too much air from the space.

That can happen, for example, in a restaurant with a powerful kitchen exhaust system.

You’re using the wrong thermostat setting
You may think you’re getting rid of more humidity by using your thermostat’s FAN ON setting. When you use this setting, the fan runs continuously even when the AC is not running.

Your older unit simply can’t handle the load
As your air conditioner ages, parts wear and it may not run as efficiently as it used to. That tendency is increased when the system hasn’t been regularly maintained. In addition to inconsistent temperatures and inadequate cooling, you’ll start to notice poor HVAC humidity control.

[tl98466]

I've used a gas furnace for years, but after some very hot summers here in Washington State and after attending some heat pump workshops, I decided to splurge on a heat pump. Mine has been amazing at keeping my home comfortable in the hot summer months and it heats my home very well during the winter. I am very pleased - I guess I just got lucky? 

[OnlyShopsOnline]

I've gotten used to having heat pumps over the last 30 years.  And, the most recent two we've had have been very high efficiency.  So, I think our electric bills are pretty decent.

The one thing I would do is have it checked for coolant, if your house is feeling humid.  I remember our last unit had some coolant leakage issues.  And, when it wasn't fully charged, the house would start to feel humid while the AC was running, and it would run more often.

This unit that we have now has phenomenal AC capabilities.  It was 97 and humid today, and the house is more than comfortable.  

[151949]

When we got married 35 years ago heat pumps were the newest thing and we put one in our new build home. They really need to be in a house that is well insulated, and you need a good backup resistance heater as well for those times it turns cold suddenly and the heat pump can't keep up. We had a trane both heat pump and resistance heater. We had an all electric home and we were warm & cozy all the time and our electric bills were very reasonable. Esp. when you live up north , you need to understand how a heat pump works so you can appropriately use the back up heater. We had to replace that heat pump after 20 years. That was a pretty good life span. We bought another Trane.

Here in Fl. we also have a heat pump but here we mostly use it for AC. This winter was cool and we had to use the heat quite a bit and it worked well for us , even though it had not been on heat setting for several years.

With any heat pump you need to have them regularly serviced, about once a year. It's money well spent to prolong the life of the unit. It sounds like the OP needs to have an HVAC guy come out and look at her unit. If it hasn't been maintained it may be close to the end of it's life.

Editted to add - here in Florida we do not need , nor do we have, a back up resistance heater because you don't get sudden drops in temperature like we did often in Pa. My DH is an electrical engineer and he chose this type of heat for our Pa. home because they are much more energy efficient but , if you have one, you need to understand how they work - why you have that back up furnace in the celler (if you live up north) and when & how to use it.I know many people just leave the back up furnace on all winter - then they complain because they have astyronomical electric bills. The furnace (resistant heater) should only be used vwhen the temp drops suddenly and then you just use it long enough to get the house warm , and put it back to standby, or if the temperature drops to some riduculous low temp like below zero - you would need your electric furnace full time because there is no heat for the heat pump to extract from the air. 

[novamc1]

I've never had a heat pump, but have sold homes to real estate clients that do have them.  The theory behind the value of a heat pump system is that all of the energy use actually  goes toward providing the heat and air conditioning.

I recently moved to a newly built home with a gas fireplace, and every day, all year long, the little light is lit in that fireplace to indicate that gas is turned on and being used.  We were advised that if we shut it off (because we almost never need or want to fire up that gas fireplace), we will have to pay someone to come turn the gas supply to it on again.

We supposedly pay pennies per day or week  to keep the gas operational in that fireplace, but I will  have to spend a few more cold winters here to decide whether paying for this gas supply and readily operational fireplace is worth it.

Maybe someone more experienced than I am can weigh in on this.  I admit I know little beyond what I've been told.

[drizzellla]

My only experience with a heat pump, is when my company moved into a newly built building. It was hot in the summer and cold in the winter. We had a contract with a HVAC company. They were out to our building about once a month. It really didn't matter what they did. We still were hot in the summer and cold in the winter.

And there were a number of dehumidifier machines in the building too.

[151949]

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@drizzellla wrote:

My only experience with a heat pump, is when my company moved into a newly built building. It was hot in the summer and cold in the winter. We had a contract with a HVAC company. They were out to our building about once a month. It really didn't matter what they did. We still were hot in the summer and cold in the winter.

And there were a number of dehumidifier machines in the building too.

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Heat pumps have to be kept serviced or they simply don't work. That or whoever is in charge isn't putting the thermostat low or high enough.

[SahmIam]

@Carmie  I would really like to know what type/brand of HVAC you have that keeps you warm during the winter and doesn't cost a huge amount to do so. Seriously. We have one now and blowing cold air during the winter is...horrible. Yes, it keeps you warm but only you have it on a high number and want to pay to run electricity all the time. Any info would be great as everyone in my community HATES them. 

I've had gas, oil, steam (boiler) and a heat pump. The best was the steam/boiler. Loved it. 

Heats pumps are AC units that blow hot air when the electricity is on only (and when you switch the HEAT on). It blows out the air based on the thermostat that is in the house to "maintain" the temp in the house. The only time actual warm or hot air blows out is when the electricity is on and you're paying $$$ rates for that.

When I was in Maine, North Dakota and Minnesota, I didn't see a heat pump anywhere used for heating. The further south and west I went, that's all I saw. It makes sense when you think about it since the areas with the hottest temps really don't need something that heats well but they do need a great cooling system and heat pump does just that.

Last, over the years, I've asked those in the building industry why heat pumps? Answer: they're cheap for the builder. The #1 goal for the developer and builder is to make the biggest buck with the smallest investment. Heat pumps are cheap; especially when you buy them in blocks (high inventory). Gas lines cost money; a LOT more than popping in a heat pump. Our local gas and electric company has a site where you can sign up to be alerted when natural gas is available in your area. It's been 28 years and so far, no natural gas to this area/community. Looking around, NO community including those being built now, has gas....it's all heat pumps. There are areas where gas is simply not available; I do believe we live in such an area.

Like said, it's great for the hot weather but in the winter? It stinks. Horribly.

[Sooner]

They tell me they are better, but I personally would never have another heat pump.  At least where live in Oklahoma.

[151949]

The thermostat on a heat pump up north should have 3 settings. Cool, heat and emergency heat. The cool is air conditioning - the heat is heating via the heat pump and Emergency heat is to turn off the heat pump and heat with your resistant heater - which is very expensive. If the temp drops quickly and the heat pump can't get the house warm you should turn on the emergency heat until it is warm - then turn it off and go back to the heat pump - it should be able to keep it warm once it's up to temp.If the temperture falls below zero - you have to use the emergency heat exclusively , and it will run up a big bill, but at below zero there is no warmth for the eat pump to extract from the outside air. I'm sure the heat pump came with directions about how to operate it.

Heat pumps work great if the owner understands how they work and how to operate them efficiently, and they save you a lot of money.