Geothermal alternative?

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ctaco

New Member
Nov 8, 2015
12
NY
I purchased a home several months ago that has no central air and electric baseboard heat. There are too many trees to get most big equipment into place and one installer already told me they wouldn't be able to do it.

I'm very new to alternative energy and really only know about heating homes with oil, wood and what I've read about geothermal. I've heard of different types of heat exchangers that use air instead of water but I'm having difficulty finding information about it because everything seems to go back to geothermal.

I'd rather spend more up front and have a system that can heat and cool my house and lessen my carbon footprint if possible.

What options do I have that don't require really big equipment on my property?

And if you have any links to share about different options I'd love to read them. I'm trying to educate myself as much as possible but it seems like articles are either really dumbed down or for people who already have knowledge on the subject.
 
Air to air heat exchangers don't work as well as it gets colder and often have electric heat backup. They aren't as popular up here for that reason. Are you looking for heating and cooling or just heating? Some of the best money that can be spent on heating is a 12 pack of caulk tubes. Stopping the drafts makes a big difference in heating bills. Intelligently adding insulation is a winner also. They fit perfectly with your desire to spend a little up front and be comfortable for life.
 
Ductless mini-split heat pumps. There is info about them all over the place - check out the green room section for one place.

They might not quite cut it for the coldest parts of your winter, but I don't know what your winter is like. So you could use a bit of your baseboard as needed, or put in a wood stove to supplement.

Edit: Duh, this is the green room, ooops..
 
Ductless minisplits definitely are good for supplemental heat and easy to install. They put out usable heat down to 10 F and run down to -10F albeit tiwh far lower output. They are not primary heat so you need a backup be it woo, oil, propane or electric.

I live over in northern NH and haven't turned any backup on yet this season running off of one minisplit for a small home. Most folks would need a couple of them.
 
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I'd prefer something that can both heat and cool a house. So ductless minisplits are a type of air source heat pump with units in each area of the house, right? Our lowest temperatures are around 30F and it gets up to around 85-90F in the summer.

I'm having a wood burning insert installed which can heat most of the house but I worry that the upstairs bedroom might not get enough heat unless the doors are always open. They open into the living room so it's not the best option to have to leave them open all the time. But it seems like with the ductless minisplit I'd have to have a unit in each room or leave the doors open anyway. Is that accurate? I know it seems stupid but that's a big concern of mine. That's the reason I'm looking at supplemental heating to the wood burning insert. I want to be able to leave doors closed and not worry about the room getting chilly.

What about reverse cycle chillers? I was just reading about them and it sounds like great idea because you can use the water to distribute the heat through baseboards like conventional heating systems...but I've never heard of it before so maybe there's some flaw I'm missing. Do you guys know much about it?
 
If your house has largely an open floor plan, biggest bang for the buck (after caulking and insulation) may be a wood stove in a large living space, which is what we do to heat our 1500 sq ft house, including temps into the -30'sF. My preference would include adding a mini-split for shoulder season heating (outside temps down to about 30F) and some AC in summer. We have lots of refiring the stove in the shoulder season which is a little bit of a hassle.
 
Mini-splits can heat and cool. If your lowest temps are only 30f, that is sounding like the definite first choice.

The doors question would depend on your layout. Some get good distribution from room to room, others not so much. One for every room is not a definite thing.

Your existing electric heat - do you mean a resistance heater in each room, or do you mean a hot water baseboard in every room that is heated by a central heating unit? i.e., an electric boiler?
 
We have resistance heaters in each room. It used to be a summer house. We replaced most of the windows, insulated what we could and caulked. Surprisingly there was actually a good amount of insulation in the walls for a summer house.

Our layout is a bit funky because it wasn't built to really be lived in full time. If I have the heat in the living room on but not the bedrooms they're noticeably colder, even with the doors open. I'd say there's a good 5-10 degree difference depending on how long the heat has been on. The fireplace that the insert is going in is actually in the basement. It's the only space it could go. With the layout I couldn't even add one upstairs if I wanted to.
 
As mentioned mini splits heat and cool and they typically are more efficient than a standard heat pump air conditioner for cooling. The major trade off is distribution of air. A mini split is not going to work well in house with lots of small rooms with poor air flow as it has no ducts, therefore all the heat and or cool air is distributed in the room where the head unit is. There are multi head units that have recently come out on the market but they are pricey and far more complex.
 
That might end up being an issue then. Eventually the layout is going to be opened up but right now it's not at all an open floorplan. I can't even hear what someone is saying from the living room if I'm in the kitchen.

And all my doors are tiny too lol

That's why I'm trying to figure out a way to distribute heat more like a conventional radiant heating system.
 
You must have a budget idea in mind? Anything that involves retrofitting a central heating/cooling solution will be very expensive and have lots of challenges in routing of ductwork (and maybe barriers) - which may leave only space heating/cooling solutions. You already have a system in place for supplemental heating of rooms as needed, and adding the insert should add some fuel economy. Although if the basement is not very well insulated it may not do as good as you would want.

Mini-splits.

Edit: And opening up the layout at the same time.
 
The basement is fully finished and its insulated pretty well. It was actually dug out after the house was built so they built it to be usable living space.

Budget wise I'm not really limited. I've been saving up since before buying the house and planned on spending at least 15-20k on a heating/cooling system.

I wouldn't mind using the existing electric heat as a supplement but I still need AC for the summer because the boyfriend whines too much when it's hot out lol. So I figure if I'm going to get a system I'd rather get heating and cooling in one shot for the whole house.

The previous owners had a few estimates done for oil heat that were around 5-7k. They seemed to think there was space to do piping for baseboards.
 
You'll likely have to lean heavily on a local HVAC contractor then. Retrofitting a central system in will have many challenges & depend on site-specific assessments & recommendations. I am quite sure you would need to go with a ducted forced air solution for central - ductwork (and the central indoor units themselves) takes up quite a bit of space and will likely disrupt your finished basement. Mini-splits take up very little indoor space.

Make sure to weigh the outcome of that assessment vs. a couple of mini-splits together with the opening up of areas that you mentioned you are going to be doing anyway.
 
Strategically placed ceiling fans can do a lot to minimize or eliminate a need for AC.
 
I complete agree with you jebatty but my boyfriend grew up with his house being 60F and is always hot. He complains when it's 65F. Most of the house decisions have been mine so I only feel it's fair to let him have AC if that's the one thing (besides giant TVs) that he wants. I've never had AC. I don't even use it in my cars.

I'm definitely going to have to look into these minisplits more. I don't have much outside wall space because most of outer perimeter is windows so that's another consideration too. Do you know how wide/tall the average wall mount is? It does seem like it'd be difficult to get any ducting into these walls. I actually think the only space without windows everywhere are the bedrooms on the main floor.
 
You have mentioned wanting even heat in the rooms multiple times. Wood heat generally doesn't give that.
 
You have mentioned wanting even heat in the rooms multiple times. Wood heat generally doesn't give that.

The reason I'm looking into additional heating for my home is because I know I won't have even heat with just the insert. Otherwise heating wouldn't be a concern to me because the insert is technically big enough to heat my house.
 
You mentioned above that eventually the layout will be opened up.

I think I would move that up the priority list, and do that first. Or at least plan it all out & do at the same time as any changes you make to the heating/cooling system(s).

Depending what you do on the heating/cooling side from here on out, opening up the layout later might make some of what you do now on the heating/cooling side redundant, or might turn up things later that you could have done more efficiently at the time 'had you known'. Changing layouts and opening them up can greatly up the effectiveness of some 'space heating' solutions.
 
If your house has largely an open floor plan, biggest bang for the buck (after caulking and insulation) may be a wood stove in a large living space, which is what we do to heat our 1500 sq ft house, including temps into the -30'sF. My preference would include adding a mini-split for shoulder season heating (outside temps down to about 30F) and some AC in summer. We have lots of refiring the stove in the shoulder season which is a little bit of a hassle.

I agree.. my house is ~1500 ft^2 ( two floors) in northern Ma . The wood stove (progress hybrid) gets used in the dead of winter. The ductless mini-split ( Fujitsu RLS2) is left on all the time. If I get home late, or stay away for a day or two, the mini-split keeps the place from freezing

And, like you, the mini-split bears the load in the shoulder season .. During the summer, I really don't use it for cooling , except for those 3 or 4 days in late august when the heat and humidity are unbearable

As to refiring, when its chilly and damp in the fall we refire twice a day.. morning and evening.. it does take some attention as I have to wait for the stove to come up to temperature before I cut in the cat.
 
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I'd prefer something that can both heat and cool a house. So ductless minisplits are a type of air source heat pump with units in each area of the house, right? Our lowest temperatures are around 30F and it gets up to around 85-90F in the summer.
......?


If you got time to research, don't rule out air to air HEAT PUMPS as the technology has advanced leaps and bound recently.
They now have variable speed compressors. Also variable speed fans (in the air handler).
You would have sufficient heat (for your area's temps) and you would enjoy the AC in the summer.

Of course you would need duct work installed. :(

The unit we installed is rated to work without back-up heat strips down to 17 degrees. How's THAT for advancement in heat pump tech?;)

This will be our 3rd winter with the Greenspeed. We LOVE IT! Loved the AC last summer too. ( lowers humidity as it cools)

http://www.carrier.com/residential/en/us/products/heat-pumps/25vna0/

Low maintenance too.:)

Worth looking into IMHO.:cool:
 
I second @CenterTree.
All heat pumps lose efficiency and output BTUs at lower outdoor temps. If you size the unit (correct tonnage) to provide enough BTUs at your typical Jan lows (I would look it up on the internet), then the HP will carry 90% of your heating needs, and the backup is just there for cold spells.
If your low temps are really in the 30s, you would be near the coast in NY, and your climate woudl be the same as mine and HPs are very doable. If you are upstate and your Jan lows are more like 10°F then its harder (but HP could still be a economically viable idea to reduce strip heat). If your climate is colder, a HP is a great complement to wood heat....you can burn when it is under 20°F, for a couple months, rather than for 6 mos with PITA shoulder season burns.
So, you can shop for 'conventional split heat pump' systems that distribute heat through (new) ducting. They look a lot like central AC systems, but maybe a bit more powerful unit and slightly larger ducts. Their efficiency might be 10-20% worse than minisplits if you get a cheap one (single speed compressor). You can look at Carrier Infinity units (w/ variable speed compressor) that would likely be within 10% of minisplit performance (if you new ducts don't leak). While the carrier is expensive, it is still likely 1/3rd the cost of geo.
I too had an older house without central AC. I figured the HP install was only ~$2k more than the CAC install (larger ducts, extra wiring for backup heat, unit maybe $1k more) and it saved me $1k/year versus my previous heat source: oil at $4/gal.
If you are putting in CAC anyway, putting in a larger HP unit is a **no brainer**.
If your house is v large, you might get two smaller HP units, one for each floor (again like a CAC) as this would allow zoned heat and balance control. If it is smaller, one unit will likely do the job.
This is a great time to reduce your BTU loads via a pro energy audit and airsealing job. This is allow a smaller unit to cover your needs.
The HP size can be estimated from your electric bill and local 'heating degree days'. In other words, figure your warm weather elec usage is your baseload, and take a recent month that would be higher, subtract the baseload usage to estimate the amount needed by the baseboards for heat. Divide by the heating degree days (might be on the bill, or get from internet) to estimate kWh/degree day. That can be converted to required tonnage pretty easily.
A lot of this can be looked up if we know your zipcode or nearby town with similar climate.
 
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