Is there a cost effective way
Is there a cost effective way to do that? The last time I had a company come out to price it they told me it would cost between $15-$20,000.

You have to realize this board serves many different climates and many different tastes as to what is comfortable. Design temperature for my area is 75 with 95 OAT.

Now if you put 76 at 70% humidity it wouldn’t be very comfortable. It can be easily upwards of 80% humidity where I live outdoors. My system operates the zone I am in at 76 all day with humidity readings of 50-55% typically, with swings to closer to 50% during the night time hours when the system drops to 74 degree setting.

Zone systems are a nightmare if not done properly. This is what I do for a living so what I have done isn’t necessarily what you will be able to do. Let alone find someone capable of doing it properly. Zone systems are complicated beast… and many that have come across this board rarely agree with what I say about these things. (That’s ok with me.) I’m just here to show what is possible, but most people only want to consider just one thing rather than looking at the whole system. When the budget for HVAC starts hitting the Teen’s of thousands people become weak in the knees and somehow believe there is some silver lining out there that will cure all their ills for virtually nothing.

The points you raise of air pressure are valid ones. This comes down to design of the system and in some cases the design of the home may decide if it’s a good idea or not. Zone systems are typically not a system made for all. The design as well as how you intend to use it can tell someone what they want to know.

The problem is many times when you’re shopping for such systems you are met with a salesman and not a true servicer of the equipment. The salesman gets paid to sell and after that they are long gone. So ‘most’ of them don’t care whether it really works out for you or even the next guy. They are only there to sell and any way they can do it.

It does work, when designed properly. What is a design? The invisible parts of your HVAC system that can determine efficiency, performance and the ability to work properly under the load in which it was designed.

The problem is when people look at an HVAC system they see a box on the outside and a box or two on the inside. Realistically 20 years ago this is about what it amounted to. But now that energy is so expensive you’re either forced to change your thinking or become a slave to your electricity provider.

Well, I *think* it was a coincidence (see note below), but my 15 year old 12 seer unit died the same day I hooked up a mistbox. The AC repair guy said that I had a Freon leak in my evaporative coil and that it was unfixable (they don’t make Freon/R-22 equipment any more, and it’s illegal to add Freon to a system with a known leak).

I have since replaced it with a Trane XV20i (variable speed), so I expect much better efficiency (I’m already seeing it in my consumption monitoring – about 40-50KwH less per day = 220 down to 170 KwH per day).

So, now I’m trying to figure out what to do with the mistbox. I could add it to my older 13 seer unit used in the front of the house… Or I may simply sell it.

Note: A theory I’ve seen is that the mistbox actually cooled and slowed the (already low) Freon in my system, which caused the evaporator coil to freeze. That’s why it happened all at the same time. I don’t think there’s any validity to the mistbox CAUSING the leak…

These are good ideas for sure.

Now that I’ve been running this system for over a month, I have some preliminary results. The avg temp this monthly billing cycle last year was 71 vs. 74 this year. Nonetheless, my kwH dropped 10%. It should be noted that I added a medium sized wine refrigerator as well. If the temp had been the same, and I had not added the ‘fridge, a 30% reduction that they claim doesn’t seem unreasonable.

I’ll also add that the mister is a bit finicky. Sometimes it starts spraying for no apparent reason and won’t spray sometimes when the AC is on. It may be due to the proximity to another unit that is confusing it.

MK

That light bill is ridiculous, but being in a climate such as yours I really have no idea how low you could expect to get your utilities down.

What is your rate per hour from your Utility provider? And is the market deregulated over there?

Basically how I’ve achieved such low utility bills is by cutting waste after installing the most efficient system back in the day it was new.

I’ve also converted nearly all lighting to LED bulbs. I anticipate a bump up in utilities this year that so far hasn’t materialized. This was due to repairs to this aging system of mine and using different parts just to see the effects on efficiency of the system.

Being that you’re in Arizona I don’t know what you could achieve with a system like mine over there, completely different market from which I live, but I think you should be able to ‘maybe’ get it below $200 a month with the right ideas toward efficiency and cutting waste.

Waste cutting is correlated to reducing or minimizing the amount of conditioned air to areas of the home that are unoccupied. In other words the amount you can cut really depends on how full your home is with people that want that conditioned air.

I’ve disconnected the mistbox until the AC is fixed (right now, it’s putting out air that is only ~4 degrees cooler than the room). So, the problem is not the mistbox, per se. (though good point about the heated water in the hose – though when I felt the misted water, it seemed cooler)

Given that the problem started at the same time as I installed the mistbox, there’s a chance I may have broken the refrigerant line. I’ll ask the AC repair guy to look at it tomorrow.

This is on a 15-year-old 12 seer unit… and our monthly electric bill during July/August can be $600+. (I’ve installed solar, so it’s half of that… but still high).

The mist box probably doesn’t use all that much water as it cycles and so if there are long spans of time in which no house water is used that water sits in the pipes for a long time.

Given the heat of your climate, the heat of the water for the first so many feet in the pipe may get heated to ambient temps depending on how your plumbing comes in the house. *THIS IS JUST A GUESS* I am not there. 😉 Take a temp reading of the water.

The other issue may be that the unit has sprung a refrigerant leak just as you were hooking up the mist box or you caused the leak in how you put the mist box on your unit. (refrigerant piping is extremely fragile these days.)

PS: My light bill was $64.36 last month live near Katy, Texas (suburb of Houston) 76 all day long, 74 at night. House is zoned and I only run the zone I am using, the rest are off.

I don’t use mist box or any solar type equipment. Just high efficient 2 stage 18 SEER AC, zoned with 4 zones, the equipment and duct work in the attic. Lowest bill was $38 and some change.

That being said, I’m having an AC repair person come out on Monday to do a tune up of the system. My evaporator coils (inside) had ice on them last night… so I cleaned them and replaced vent filters. I also turned off mistbox. Still have the same problem with the AC – it’s constantly running and unable to keep set temperature.

I’m thinking maybe there’s a problem with the refrigerant in the system… and it just happened to show itself the day I installed the mistbox.

I will let everyone know what the AC repair guy says next week.