I don't live in AZ, but leaving buckets of water around sounds, ummm, silly, being that refrigeration/air conditioning by nature removes moisture. Moisture would be removed when the a/c is running, so what's the point of attempting to add moisture when the a/c is off?

Regards to recovering a comfortable room temp ... a/c is most efficient when it runs for long periods, so setting the desired target temp and letting it run long as necessary to get there seems the best choice.

Be glad that your home is in a dry place. Skip the buckets, lock the door and don't worry while you are gone. On the other hand, if you are storing things that are expensive and very sensitive to humidity changes, like violins, you should probably invest in a capable climate control system. That part of Arizona is generally very dry, but the humidity can go above 30% during the monsoon season. That is a big change since a lot of the time the RH is below 10%.
I never heard of anyone putting buckets out while they are gone.

Thank you very much for the information. Especially about leaving the AC running until totally cooled, when returning. I think I missed the point of turning the AC off while we were gone, with some of you. It isn't the lack humidity but rather the heat that dries out such things as the carpet backing and wood floor glue, etc. The buckets of water are more to reduce that possibility, rather than to raise the humidity in the house.

Still, I have never heard of anyone in Arizona leaving buckets of water around when not at home, at least not in Tucson. Maybe it is a Phoenix thing, but up there, people watered their lawns!

A few buckets of water, leaving the bathtub and sinks full of water are not likely to reduce the temp of your house significantly. That is why evaporative coolers need big pads, a pump and a blower.

Ok, so I'm no expert but I think the water idea would work for you. Why not check with your extension office? In my house, I have the opposite problem of too much humidity, so I have a dehumidifier and use exhausts to deposit the condensation from showers and cooking outside. I would fill up the bathtub and sinks too and let the water evaporate into the air. In Fla, no A/C = mold, so we leave it on, even if we're gone to save our belongings. In the desert, your furniture could crack without enough moisture. It all sounds good to me. And as far as when you return, I would probably open all the windows first and use fans, then turn the A/C on and let it run for several hours at a time to achieve your temp over a few days. With temps in the 120's in AZ, it will prob overtax your unit with continuous running. I'm shooting from common sense here, nothing more. Good luck :)

Thank you all for your advice. I have talked with some winter visitors in a senior community and they all agreed that the buckets of water helped keep household items from drying out, so guess I have nothing to lose doing it. Thank you for the advice on recooling upon return. I will use the advice given here.

Usually, the AC in Phoenix does not remove any humidity from the air in the house. Why? There isn't any. It is not uncommon to have humidity readings of %5 or less. In the summer perhaps a bit more.

Sometimes common sense really means common ignorance. This thread is in danger of sinking in the realm of new age logic (if it sounds good, it must be true). Can it be raised to the realm of facts and reason? I was going to give up, but if Weedmeister is trying, so can I.

O.P., you are in Arizona. They use evaporative coolers there (AKA swamp coolers). They have relatively huge blowers and evaporative pads to evaporate relatively large amounts of water into dry air to cool it. How do you think that your dinky buckets are going to have any impact at all? Try talking to long-time AZ residents instead of the snow birds. In communities like the latter, stupid ideas can spread like a prairie fire.

Starhikers, use your head! How is a continuously running HVAC system going to be overtaxed by cooling the air? That is what it is designed to do! How do you know that the furniture is going to crack? As Weed pointed out, typically dehumidification does not happen with conventional HVAC systems in AZ.

OK. I think I have gotten all the imput I need. I've decided the buckets can't do any harm. I AM a long term resident. I've been here for 64 years. I have had wooden things in my garage come apart from the heat "cooking" the glue. Don't want that to happen to my wood floor.
Also, we had a swamp cooler 30 years ago, but can't remember the last one I saw except perhaps an "old timer" who has both so he can use the swamp cooler in the Spring and Fall. Too ineffecient even in Phoenix.

O.K., sorry if I was a bit terse. That is one of my points. You can't depend on the buckets to keep your temperature down and save your temp-sensitive stuff. It just won't work because there is not enough evaporation If you have a solid wood floor, there should not be any glue in it. If it is a manufactured floor, I would check with the manufacturer for a max temp rating.

Evap. coolers were plenty efficient in Tucson 20 years ago. They just don't work that well in Monsoon season and water is getting more precious all the time. At that time, the water use per capita in Phoenix was twice that in Tucson.

She's not trying to keep the temperature down. She's trying to keep the humidity up.

She could have used better language, but read again,

"It isn't the lack humidity but rather the heat that dries out such things as the carpet backing and wood floor glue, etc.".

It won't make a significant dent in the humidity either.

I decided to call a couple of air conditioning companies here in the valley. They all agreed the buckets of water actually do work, for whatever reason.
I got so many different opinions, I guess I should have called them in the first place. Thanks all anyway.

You're typically away for 2 months ... assuming the buckets fully evaporate before you return, who is going to refill them?

Ask them for supporting data. This is just more new-age logic. Is there a case study that shows that a couple of buckets in a hot room reduce the temp significantly? How about just a model using the heat of evaporation of the water and the heat gain of the room on a typical summer day? This should be fun, but please tolerate some rounding here because it makes it so much easier.

A gallon of water absorbs about 9000 BTU of when it evaporates. Assume that you put two buckets each containing a gallon of water in water in a room that normally requires 9000 BTU/hr to maintain at 80 from what it normally might be, 120. I think that is reasonable Despite the fact that people here could argue from sunup to sundown about what might be an average room.

In a whole day, how much of that water evaporates? Maybe � bucket if you are lucky. So you have evaporated 1/2 gallon of water, at most, or 4500 BTU. Big deal, that is like having your AC on for a total of 30 minutes a day. You might want to look at it this way, spread out over the 24 h day, that is 1.25 minutes/hr. Is that going to help? What are your typical run times for the AC if you want to maintain a 80 F temp on a hot summer afternoon, one minute/hr, 5 minutes/hr, 30 minutes/hour or 50 minutes/hr?

If my assumptions don�t match your situation, feel free to play with the numbers. Maybe you can make it work for you.

What can it hurt? Don't termites like to have water near?

Dear Ionized,

I see no reason for you to insult other posters. I posted stating I was using common sense. I am not a HVAC tech with a 6 mo certificate. I do have however, a working knowledge of the hydrologic cycle.

We have structures today which are essentially flawed. We would all be better served health-wise,living in tents. Then, we would have no problem with heating and cooling. But since we like the indoors, we have to adjust our buildings to the outside weather. Condensation/Humidity is a real problem in some areas. In Florida, we have severe humidity and we have mold issues because all natural fibers (and some others)are prone to become moist for prolonged periods and grow mold(i.e. spores+temp+food source+moisture). An air conditioner must control the humidity in the air to be effective in Florida. Therefore, in a desert climate, like AZ, which is essentially the opposite of Fla, you must add humidity to the air so that wood does not dry out. That's what "desert" means, it's not something to eat after dinner(i.e.dessert). Water evaporates into the air and that water is dispersed throughout your home no matter where you live. There is nothing wrong with filling up water containers and bath tubs while they are gone. Since they are not leaving the A/C on to keep the temperature in the house low, the hotter the ambient temperature is, the more likely wood will be damaged. In Fla, wood can warp which is the opposite of drying out, now isn't it? And as for your remark about leaving the A/C on when they return......if the temps have been over 100 degrees for long periods(desert weather, 110-120 degs at times), then it only makes sense to slowly cool the house and not over-tax a unit which might have to run all day and night for several days to reach the desired temperature and too because the bill for that cooling is likely to be astronomical. So, think outside the box Chief, you may just be wrong on this.

I am sorry if I insulted someone. I can be abrupt, but how is showing someone that a process is futile an insult? How can pointing out why someone is wrong insult them?

Discussion of mold and high heat and humidity are really OT. So are mealtime customs. Since you brought them up, however, I have lived in the Sonoran desert and the humid Gulf South. In addition, I enjoyed dessert in both places. The Sonora Alta is a relatively rainy place for somewhere defined as a desert. Despite the semiannual rainy seasons, humidity-related mold and problems are rare. I know how mold grows, as well as other things grow, at a much deeper level than you can probably imagine. If you want to catch up, plan on taking classes, or hitting the library very hard for a decade or so.

For the OP, it is a byproduct as the stated aim is to COOL the house by evaporating water from buckets. I believe that I have already shown that the decrease in temperature is not likely to be significant. I, personally, would be interested in any demonstration that you might make indicating that a few buckets of water will significantly increase the humidity in the Phoenix home. I would sometimes turn the shower on and plug the tub drain when I came home in the evening and started the forced-air heat. That was effective in increasing the humidity inside of that small house. My little portable ultrasonic humidifier could never catch up if I did not do that.

Any modern residential air conditioning system in good condition is not going to be harmed by turning the thermostat on and letting it run. If you have a different view, please explain your reasons in detail.

As for the cost of running AC continuously vs. intermittently, you statement makes no sense as written. Maybe you can explain what you mean. Purging the home with outdoor air using fans or blowers makes sense. Sure, running the AC a little at time will cost less, but the indoor temp will be high in the day time. In that climate, night temperatures are often pleasant enough to open the windows although in urban areas that is may not be true. Do you expect the OP to come home in September and only run the AC a couple of hours a day until November?

Prove me wrong, by facts or logic, and I will concede the argument. Hand-waving opinions are not sufficient. Thinking outside of the box is how a lot of so-called common sense is debunked. That is my usual approach.

The antonym of warp, btw, is not drying out. It is true, or straight.

my misunderstanding. I saw "...place buckets of water throughout the house, to avoid carpet, wood, etc from drying out..." and thought 'humidity problem'.

Personally, I like sparring with people. Others may find it insulting or boring. But please just read the original post and I think you will find that the writer was asking for a way to save the furniture by adding moisture to the air, not cooling the house with buckets. I don't think anyone here even gave that a thought......

"My husband and I leave home (in Phoenix - very warm and dry), for 2 months in the summer. I have been told, that we can turn off our AC and place buckets of water throughout the house, to avoid carpet, wood, etc from drying out. Is this true, and if so, when we return, do we cool our house back down by cooling a few degrees then letting the air conditioning "rest", then recooling, etc., or cool down all at once. (It would probably be about 10-12 degrees higher than wanted."

I'm willing to concede that lots of people are more fluent in "mold" than I. I just know that bleach it my best friend when I have a problem.

As far as the intermittent argument: I have always left my thermostat alone. However, from experience and testing the theory that it makes no difference in energy consumption, I have witnessed in our second property, that indeed, it does make a difference to turn down the thermostat during the day. When we are there, we often leave during the day and return in the evening. Leaving the temperature constant resulted in a bill significantly higher, sometimes even twice as much. So, given that the insulation may differ in each property and other variables such as sq footage etc. which is certainly a factor, it would appear that adjusting the therm. at times during the day is a clear winner.

As far as the original poster comment, I stated over a few days, not months, to cool the house when they returned. But then, your tendency to exaggerate and twist the intended questions and answers is obvious to those of us reading this. Perhaps mold has invaded your cerebral cortex.....ps. you don't do much building do you? The opposite of splitting wood is warped wood. In one case, the drying of the wood makes it split, the water content in the wood make it bend or warp. Check it out!

Enough said on this topic!

Enough said about this topic? Maybe, but you are still wrong about the ability of a few buckets of water to change significantly the temp or the humidity of a Phoenix home in the summer. Show me a model or show me some data. Hand-waving is not adequate.

You are still wrong about stressing the HVAC with continuous running. Yes, thermostat setbacks are a good economic move. That is a no-brainer. You can approach it theoretically by thinking about heat transfer rates, or look the DOE web site. It is a well-known strategy. What does that have to do with continuous running of HVAC equipment being bad for it? You are trying to win an argument by changing the argument.

A few days or a few months makes no difference. The fact that continuous running of the HVAC will not hurt it, does not change.

Give up your fear of mold. Fungal brain infections are rare in individuals that are not immune-compromised.

Is English your first language? Water content makes wood warp and split. High levels tend to warp and low levels tend to make it split. The opposite of warped wood is straight or true wood. The opposite of split wood is intact wood.

There really is no sense continuing this conversation. The control freak personality requires that you be "right" about everything and to have the last word. Those traits are typically synonymous with being "male". It's not something that can be addressed in this forum.

Fro example,I could ask about your comprehension of the English language, but then what would be the point? You insist that everyone wants to use buckets of water to cool the home, when no one ever stated that. So, perhaps English comprehension is not your forte.

And your lesson in antonyms is also futile....is the opposite of stop, go? Or if you are referring to cars, is the opposite of speed/slow or speed/obey speed limits or speed/stop? It really depends on the context, but then if English is the problem here, I can't hope that you'll understand.

In response to my light-hearted suggestion that you have mold in your brain, it was really meant as a joke. In America, a writer often utilizes humor to point out preposterous notions,( a synonym of nonsense)in a less harsh way.

Also, I am quite aware that anyone can "google" fungal infections of the brain. But since you brought it up, immunocompromised individuals are increasing at alarming rates, why not "google" that as well? I do have trouble though, believing that in addition to being a nuclear physicist, toxicologist and mechanical engineer you still find the time to practice neurology and infectious disease.

So, goodbye, good luck and good sense. ps.(that means this is the last time I will read or respond to this nonsense)In plain English, it means please stop.

It is not nice to be a sexist sow. Show me how I am wrong with a valid argument or solid data and I will accept that.

There is nothing in your post that is relevant to the original poster's issues except buckets of water. The OP wants to cool, not humidify a house in the Phoenix area by putting buckets of water in a home there. That was clearly stated in a follow-up post:

" It isn't the lack humidity but rather the heat that dries out such things as the carpet backing and wood floor glue, etc. The buckets of water are more to reduce that possibility, rather than to raise the humidity in the house."

My question is if you decided to leave the air conditioning on while you were gone to prevent damage to things like computers, tvs, and melting of plastic items. What would the highest temp that you could get away with to save money on the one hand, but protect your stuff on the other hand. Would 90 degrees be too hot? I heard lap tops can melt at 95 degrees.

We have lived in north central Phoenix for five years, going north for 4 months of summer. My husband always had 5 gallon buckets of water set around to "keep the humidity at a safe range". One June I had to come back after 3 weeks being gone, and the buckets were almost empty! So the rest of the summer the house was without extra humidity,

My question is do I unplug my reverse osmosis system while gone for 4 months?

That is great feedback about the bucket issue. I suggest that you start a new thread in a water treatment forum for the RO question. My feeling is that without relatively constant use, any water purification system that strips out all the disinfectant (chlorine) and leaves the water stagnant will allow microbial growth. Your system manufacturer must have a procedure for "mothballing" the system and restarting it.