Need opinions on mini split

[toadman77]

Hello. I had a 18000 hyper heat mini split installed this past fall in my living room. I am very impressed as my electric bill has been so much cheaper. What I need help on is adding some more heat to the rest of the house when its in the low teens and below and to give the 18000 unit some help during defrosts and so maybe help the cop. My house has all electric radiant heat until that addition except the basement which has no heat and has quite a bit of moisture from no heat. Temps in the basement can get down to 42 ish and it mostly underground. i thought of a few options and looking to see what would be the best. I attached a rough drawing of the main floor to give an idea and where the current unit is at. I sized the 18000 unit due to being the hardest to heat and the extra heat for the negative temps. AC is not an issue since the house is cool in the summer. Location is south west pa.

First is just put a hyper heat or fugitsu .75 ton unit in either the spare bedroom to push heat out to the back of the house though I'm not sure if its worth doing since the bathroom and bedroom are not bad . I use a box fan to push the air out of it to the living room. Or I could put it in the dining room to push the air to the kitchen where it was chilly. The unit could be either a floor or mounted near the floor on the opposite wall of the kitchen walkway. Other idea though I don't think it would help the main floor is mount it in the basement. These units have around a 13.5 hspf.

Next option is do a 20000 hyperheat dual mutizone unit. If I do that I would have to decide which one of the three areas don't get one. 10 hspf

Last option is a 24000 hyper heat tri unit. I could heat all those areas buts its going to probaley cost $1500 more I really don't think its worth it. 10 hspf

Any ideas would be welcome. I also don't have natural gas or ductwork in the house. House and insulated really good but need to replace a few windows eventually that are older but double pane.

 

[begreen]

Normally one puts the heat where folks spend the most time. Putting it in the dining room pointing toward the kitchen seems to satisfy that need. I would space heat the other areas. Is the basement fully insulated?

 

[Grisu]

How about adding a woodstove?

 

[toadman77]

The basement does have insulation in the rafters and half the walls are down. I don't know how effective It is because of the moisture. I don't know if it's worth putting a unit there or not.

 

[toadman77]

Wood stoves are nice but not something I don't wanna deal with Between getting wood and ashes. Thanks for the idea though.

 

[begreen]

The reason I asked was thinking whether heating the basement to warm up the floors and keep it drier would be worth considering. What is the source of moisture in the basement? Condensation, poor sealing, rain water not being diverted properly, low water table? Do you run a dehumidifier down there now?

An alternative to a wood stove might be a pellet stove?

 

[toadman77]

Once in a while i get a little water from a big storm. I run a dehumidifier during the summer months but the rest if the year it doesn't pull much water out probably because it's chilly . If one was to be installed would you wanna take out all the insulation in the rafters?

 

[begreen]

If there was heat in the basement and it was kept warm then yes, I would remove the basement ceiling insulation and insulate the walls. But first I would address the source of water coming in. Sometimes this is a simple as cleaning gutters and directing the output from the downspouts a few feet away from the house. Sometimes it is more complicated needing a french drain installed on the upslope edge of the house.

 

[toadman77]

I know there's an outside French drain and the water runs away from the house. Its only a couple times it happens. Would you do a dual unit or do two separate units.

 

[begreen]

Based on the little I know about the house and how it's used I would probably go for the higher efficiency unit in the dining room and space heat the bedrooms. This is assuming there is little need for the basement for anything but storage.

Question: Are power outages very rare in your area?

 

[toadman77]

Thanks for the help. I'm goin to look at either a .75 ton hyper heat heat or a fugitsu .75 ton floor model which would look better in there. Between the two that should be around 25000 btus after defrost and any loss of heat under 5 degrees.

 

[toadman77]

I forgot to ask do you think they would interfere with one another?

 

[begreen]

No. Also look at Mitsubishi equivalent for great low outdoor temp performance.

 

[maple1]

No. Also look at Mitsubishi equivalent for great low outdoor temp performance.

hyper heat = Mitsu.

I think?

 

[Highbeam]

hyper heat = Mitsu.

I think?

Yes, mitsu is hyper heat. The multi head units cost way more and are lower efficiency. Singles are better for the additional benefit of independent systems so if one dies the other still works.

 

[maple1]

I'm pretty close to going to get an estimate from the local Mitsu people. Many more hot days like yesterday (hot to me anyway) and might be a done deal. The dual head has my attention, it would work pretty good for what I have in mind I think, despite the bit of a hit in efficiency- but will run thru the choices with them when I do get to talking.

 

[toadman77]

I did see they got muti zone hyper heats. There about a 10 hspf. My single unit I have now is 10.3hspf. The new single zone hyper heats get up to 13.5 hspf.

 

[toadman77]

Post back with what they tell you about the multi zone. Supposely there compatible with a whole bunch of inside air handler units.

 

[toadman77]

I was wondering has any one tried the ducted unit? I'm assuming you would need a return duct and was wondering how it monitors the temperature since it would be goin to separate areas.

 

[begreen]

I almost put one in back in 2006. Unfortunately no one had installed one yet in our area and the only brand sold was a Sanyo unit. I ended up installing a high-end American Standard with a variable speed air handler instead. Now there are lots of choices and I wouldn't hesitate to try one. Yes, it will need return(s) ducted in. Temperature is monitored and the unit is controlled by a wired or wireless remote thermostat(s). The main limitation is size. They don't make them in 36,000 btu units so for our house we would need two.

This site has pictures of several ducted mini-split installations:
(broken link removed)

 

[Highbeam]

I was told that the remotes don't actually monitor temperature but the unit itself so you would want to be sure that the return air is taken from the room(s) you want to heat/cool.

 

[STIHLY DAN]

you can have wired remote, or wireless and take temp from either unit or t'stat. there are 2 types of ducted units. 1 is like a traditional unit but has same modulating condenser, then there are horizontal skinny units that have to be ducted towards static pressure.

 

[toadman77]

I was wondering how the ducted worked. I think I'll stay with the other. I'm thinking of a fugitsu floor model over Mitsubishi a wall unit. It's about a $150 more. It still does negative temps to. I would probably use it more during the off seasons since the 1.5 ton short cycles a lot during the 50 and up days.

 

[STIHLY DAN]

These don't short cycle they modulate. They are at the most efficient at 47*

 

[toadman77]

I read somewhere that they short cycle and it's hard on the unit. Adding a second unit should bring the cop up in the winter I would think.