[Cybersprings]

Originally Posted by MandoMan

I recommended to a girlfriend in New Jersey in a centuries-old house that she get a mini-split system to cool or heat her bedroom and sun room. She loves it. It’s very quiet, both inside and outside, and it’s certainly much cheaper and quieter than a window air conditioner (which she had in her living room and a guest bedroom). However, here in The Villages, in a courtyard villa, I have a new high end heat pump. I keep the temp at 71° to 73° 24/7 year round and rarely open a door or window. I also drive a Prius Prime with batteries I charge every night in my garage. Last month my electric bill was $68. At that price, it would be hard to justify a separate heat pump for one area. Turning the house down to 68° at night would cost nothing at all unless the night time temp were above 68°, which is only in the summer, and even in the summer, the sun doesn’t shine on the house at night, so it’s easy to cool the house down a little more.

If cost was the only factor, you might be right.
I can't sleep well unless it is 68degrees or less in the bedroom.
I cannot survive the complaining unless I keep the rest of the house and the bedroom prior to bedtime at 72 or warmer . (My wife also spends a lot of time in the bedroom doing puzzles, devotions, etc.) To cool the whole house from 72 to 68 takes a few hours. So, it is either not cool when I go to bed, or there is lots of complaining about how cold the house is before bedtime. And in the morning, it does not warm in the house for several hours. So I end up having to heat the house to get it to 72 and then cool it. The whole thing is a nightmare.

So, I think being able to quickly cool one room to a sleep temp and not cooling and then heating the rest of the house in the morning makes a lot of sense.

I have been debating doing this for a long time, I would just never post on TOTV to get input.
I am glad someone else did so I could get the idea of the cost and results of those who have already done it.

[Romad]

If sleeping is the problem, there are a couple other products available. One that I can’t live without is a Chilipad that cools the mattress. The room doesn’t have to be quite so cool. The other is a Bedjet that blows air across the sheets. Just options that I have found helpful since I sleep warm without cooling the house more or using the ceiling fan.

[under55]

The original question was do you have one. Yes

[Dust Bunny]

Originally Posted by GreggC69

Looking at getting a mini split for the garage and at the same time adding a head for the master. Figured I could cool that room as needed (like it cooler at night and other times) without having to drop the temp in the whole house unit. Have others done? If so, did you go with the ceiling mounted option and put in the outer portion of the ceiling without impacting the trey? Or did you do a wall mount? Appreciate in advance any thoughts and ideas.

I have a wall mount in my Lani with sweeping fins. It works fine. I also had a very large one in my solarium in my other house. It was an all-glass room, worked wonders for heating and cooling.

[dewilson58]

Originally Posted by Cybersprings

I agree 100% with the idea, but it doesn't work, unless you spend a ton of money.
First of all, you have to rerun all (almost all) of the ductwork in the attic. Then you have issues with closing off zones and the back pressure that causes, which can ruin your a/c. I tried doing this with Flair to make it more cost effective, but only 2 or 3 vents could be closed off before Flair kept the others open due to back pressure.
From my research, the best way, when done as a retrojob is the mini split.

Actually.................it works great.
You are wrong about rerunning ductwork.
No issues with back pressure.
Spent less money than a mini split.
& it doesn't look like I'm living in a hotel.

[ithos]

A major drawback with using minisplits in every zone is that you have many more potential points of failure. The upside is that when one fails it only affects one area and not the whole house. Another shortcoming is that there are fewer factory trained techs to work on them.
And the man hours required to fix a mini split cassette may be more than a standard condenser unit. Especially if it is a leak. Most techs don't like to work on them.

If buying new construction I would install a variable speed compressor and evap fan with a zoned system using static pressure. The fans shouldn't be much more but the outside unit will be. But it should pay for itself in the long run and last longer because there will no longer be thousands of hard starts over its lifetime. And the new ones may be able to be diagnosed remotely as well as providing more diagnostic data with trends. The downside is the more sophisticated the system the fewer companies you can call for service. That may change as more are installed.

(edit). Variable speed is much better for humidity control if that is an issue and you will avoid that big blast of hot air when the fan kicks on during the summer.

Variable-Capacity Heat Pumps - GreenBuildingAdvisor

[mrf0151]

We tried a mini in our large southwest facing room but it has issues. We went with 4 zone system which we absolutely love. At night the master bedroom runs at 70 degrees for cool sleeping and the rest of the house is at 79. It will take a few years for this zone system to pay for itself but it is the ticket for larger homes.

[Shipping up to Boston]

Originally Posted by mrf0151

We tried a mini in our large southwest facing room but it has issues. We went with 4 zone system which we absolutely love. At night the master bedroom runs at 70 degrees for cool sleeping and the rest of the house is at 79. It will take a few years for this zone system to pay for itself but it is the ticket for larger homes.

This is a typo, right? ‘the rest of the house is 79’ Must be in the off position

[justjim]

Originally Posted by Battlebasset

Like others, not saying you shouldn't do this. But maybe do a test where you drop your temp for a month to 68 at night for your whole house, and compare it to what you pay per month when you don't drop it. Pick a couple of the hottest months for the max comparison.

Let's say the difference is $25 per month. That means 100 months, or 8.3 years you could do that for the $2500 you would spend on the split system. And if you are thinking "But that will kill my house AC quicker" well perhaps, but then you have $2500 in your pocket to put towards a new house AC,

Not perfect/apples to apples, but at least you would be going into the purchase with an idea of what your $2500 purchase gets you vs just turning down your existing AC a bit.

I like your thinking! I know in our case it would not be profitable because the difference is 75 in the day and 72 at night. 68 is just too cold for us at night! But to each his own.

[mrf0151]

Originally Posted by Shipping up to Boston

This is a typo, right? ‘the rest of the house is 79’ Must be in the off position

Nope