For me, ductless is better than having ducts outside of the house (in attic or in crawl space). If you can put the ducts inside the house, in fur-downs, it might be less expensive to install a more conventional ducted system.

Some questions are, how much heat do you want from this system and do you have natural gas available? If gas is available, what are your gas and electric rates? If you have gas, heating with that will likely be less expensive than with a heat pump. What is your climate like?

As the number of rooms increases, the relative costs of mini-splits increases relative to conventional split, ducted systems. You've lived with a good split, ducted system? You are living with window units now. A mini split system is somewhat like the latter except a LOT quieter and more comfortable.

Lastly, sometimes lifestyle is a factor. If you have a lot of rooms and use few of them at a time, the inherent zoned nature of the mini splits can be an advantage.

Miami or Minot? There is a difference.

Adding duct work to a home is difficult, costly and takes a lot of space. I eliminated all of my duct work and created two closets with the space savings. As well, it is difficult to install duct in an existing structure.

Based upon my experience with mini-split heat pumps, both as a homeowner and in my previous business as the rep for Fujitsu, I will never install another piece of duct work...ever.

Given that you are heating with wood I'm assuming you are closer to Minot than Miami. Fujitsu and Mitsubishi both make units which will heat down to -15*. Other units (which I have) will go down to 5*. Given that your primary heat is wood, you may not need to get the deepest heat units, again depending upon how you use them. IN my home I have a very high efficiency unit downstairs and it handles the LR, DR and Kitchen, all within a degree or two. Upstairs in the bedrooms I have a dual unit which handles two of the three bedrooms. This combination of the dual and highest efficiency single came in about the same cost as one triple and system efficiency and comfort is higher/better. It also allows better zoning.

You can have a very effective combination of heating with your wood stove and mshp's. In looking over my post I did not mention cooling. you will have excellent cooling and dehu with these. In the Northern climates, you get your return on investment in heat savings.

I know this is an old post, but it is exactly my situation. We heat with a coal stove right now and are thinking seriously of adding a ductless system to our home to heat the furthest regions of our home in the winter and cool every room when we need it in the summer.

I know about Mitsubishi and Fujitsu by name and reading posts. Jackfre, can you recommend my looking into others? I am actually not sure where to start talking to people about buying a unit. Is this something we can install ourselves? We do everything ourselves.

Any advice would be greatly appreciated.

Same questions apply as asked the original poster.

Hi ionized.

Our issue with running actual ducts is that our house is very, very, very old and the original very, very, very old part of our house is solid one foot thick log walls. Going through them at any point is a nightmare for anything. We have a new addition, which would be fairly easy to run duct work, but working it into the old part of the house, which also has only 7' ceilings which are completely open ceilings with timber joists (bark still on them), which we plan on leaving open. We plan on adding some sort of insulation in the flooring between levels but between solid walls, no actual ceiling space and of course no basement, a "ductless" system is seeming the better way to go.

Also, no we have no natural gas.

Not knowing a whole lot, I would guess I need to run it into 6 rooms. 3 bedrooms, living room, dining room/entry, and kitchen. Right now our coal heat is actual a free standing base burner coal stove, so not central heat. Real turn of the century stuff, but believe it or not seriously efficient and the more insulated the house gets the less I think I need heat other than it, except for the fact I am living in the turn of the century stoking a coal fire daily. Because of the log wall set up the only room that is left out is our new MB. It is on the outside of the log house in the new addition and not on the same level as the stove. So the circulation just doesn't get there very well. There is also the more temperate times of year like Oct. when it would be nice not to be running the stove and have easy access to heat at night if it gets to 30 like it did the other night.

My few real questions are do I need to have an additional heat source like baseboard heating for this type of unit? I saw a Youtube video that said if it gets too cold they don't run right. Would my coal stove be OK (we have no plans on getting rid of it and will continue to burn it in the coldest months of winter), or would I then have issues in my MB if I didn't get enough heat up there if the temp dropped?

Aslo, I read somewhere and now I can't find where, that there were 35' maximums on the length you can run from the compressor outside. Is this true of all systems or did I read this on one site or someone talking about one manufacturer? If so I am thinking I need two compressors to service different areas of the house, is this how the cost starts adding up quickly?

And do I need to hire a professional to install it? I promise we are not average DIYers. We would not be ready to install the entire system at once at any given time. I was hoping to educate myself, decide on a system, buy the parts we need as we go room to room. We are slowly working our way through the house, but we are probably looking at a 8 year total project.

Minot or Miami? There is a difference.

Given that you are using coal, I guess I can assume you are in the PA area. What a mshp will give you is a very high percentage of your heat. You will have more flexibility as to when you have to build the coal fire.

What I did in my home was to put in a dual system to handle the bedrooms. In your case a triple may be needed. As to the kitchen, dr, lr, your choice of equipment will depend upon how open the floor plan is. My dual unit is 16.5 seer where the unit in the first floor is 25 seer. It handles the adjoining kitchen/den very nicely. With our new addition going up I am installing another 25 seer in the new kitchen.

Installation of a Tjernlund Airshare will help move air as needed without adding another interior unit. Check them out.

there are, in my experience, three major brands. Fujitsu, whom I used to represent, Mitsubishi & Daikin. Other major brands are Panasonic and LG and I guess Samsung. I would only go with the main three. There have, over the years, been many brands who have "hit and run", meaning they were in the market for a few years, sold a lot of equipment and disappeared leaving a lot of orphans.

Many on this site install their own. It isn't hard if you have the right tools and know how and when to use them. Screw it up and you have an invitation to your own personal twilight zone. The wrong contractor can provide the same experience. Get references and check them out!

Your log situation sounds a little like installations in old âÂÂbarge boardâ homes in New Orleans. There are no wall cavities. That is not my situation, but I know someone that had Daikins installed in a barge board home last year and they are quite happy. They have minimal space under the house. I donâÂÂt think it can really be called a âÂÂcrawlâ space. There is no attic space either. Before this, they had resistance heat and window units. The house probably had gas wall heaters at some point. They are very happy. It is not an inexpensive proposition, but they really had no other good alternative to fix a stone-age situation with modern HVAC.

Your partition walls are log as well? There is no reason that the indoor units can not be put on interior walls if there is stud space there and a way to drain the condensate.

As jackfre pointed out, any advice on heating has to take into account your location. I wonâÂÂt offer any anyway because I am not a pro and I live in a hot climate. Read up on low temp performance at the manufacturersâ web sites. IâÂÂve included a non-manufacturer link. IIRC, jackfre is in the New England area so he is probably a great source of advice in this respect.

There are main units that take at least 8 indoor units. If It were me, I would be thinking two anyway for at least a couple of reasons. First, the main units will throttle down to a percentage of their max capacity. That means that if you are running one indoor unit at a low demand, the system can run continuously if you have the smaller compressor. If you have a larger one, it might be starting and stopping more. Second, if you have two systems and lose one, you are still in pretty good shape. I have seven indoor units and three outdoor (2+2+3).

That brings me to a related advantage of the minisplits. For two or three days last year when power was out and it was hot, I ran my refrig, freezer and two of my systems (running a max of two indoor units at a time) on a 6800 W generator. The inverter systems start up with little surge.

What you can do, once you figure out your low temperature performance issue, is install half of what you might like (3 units/one compressor) and after you have a year or two of experience, and save a little more money, go the other half.

Here is a link that might be useful: low tem performance

Jacfre, good guess, we are in MD, about a 20 minute drive from PA. I was kind of thinking something similar to your set up, only splitting the load to handle two bedroom and the kitchen, and one bedroom, living room, and dining room. Or a different combo depending on the constraints are for length of running to the compressor because of how our house is set up.

I had never heard of the Tjernlund Airshare. That will come in mighty handy for us in a few locations (I have 3 I can think of already). Thank you very much for that info.

LOL personal twilight zone. DIY rehabing a 300 year old house, I feel like we are already there sometimes ;-)

Ionized, our partition walls will be studded. We also have studded walls on top the the log in some areas. Enough to make it work for us. I hadn't thought about the power loss aspect. That is good food for thought in how I run things. We do loose power often and when we do we are some of the last to come back up as we live in a very rural area in an otherwise populated county. Service the masses first and all. Thank you also for the link.

I will do my reading and research for the big 3 manufacturers. I think hubby and I will immerse ourselves in this and decide on a system. In a month or so I will probably start a new thread with our plans and see if anyone has any final advice before we buy into a system.

Thank you both for your time and advice. It is much appreciated.