Wood heat for new house

[anlrolfe]

For the chimney, put it on the (gable) end. Form a niche in the basement wall as though you'll have a fireplace(you could later). Go wood frame box all the way up w/ stainless pipe inside. Have a "brick ledge" built on that chimney foundation area for future use. If cost is a factor just use regular siding methods to cover. Flashing along the bottom will protect. If you want later brick veneer can be added as long as iron and framing are provided on the original build. In today's day and age brick isn't critical for aesthetics on a chimney, it's your call as I see it. Save the money and just use siding... put the money into higher efficiency appliances

 

[Mustang71]

We just did all the hvac in a 4000sqft ranch over the summer and we stuffed a fire place flue and a double wall stainless flue into a fire place chase. He wanted a wood stove in the basement not that it would heat that house. For the not to much extra I would have gone triple wall.

 

[NSMaple1]

I would put the chimney up through the middle of the house. Stainless Class A. Quick & easy. That would put your stove in the middle too. Don't think I would ever do one outside up the side or end.

Ductless mini-split heat pump(s) for primary heating is practically a no-brainer for something this small being built new (unless maybe you had NG). You should be able to heat for like $1/day. And A/C & dehumidify in the summer. With a smallish wood stove in the basement to supplement or for backup you should have all your bases covered. For a very reasonable price - both up front & ongoing.

 

[peakbagger]

Thumbs up for a minisplit. I am up in northern NH and use a 12,000 btuunit to heat around 1600 square feet anytime its over about 20 degrees. Since you are building new, spend money on hard core insulation. Insulate the foundation walls and floor. Go with 6" walls and consider putting 1/2" of isoboard foam between the interior face of the studs and the drywall. Install insulated air tight boxes around any exterior wall outlets and go wild with caulking every crack and joint on the exterior envelope. Once built, spray the box sills with foam and make sure it goes down over the lip of the sills to the foundation wall. Go with a small stove and realize its not designed to run for hours at a time as that is an invitation for chimney fires. Think small fires that you keep going by adding wood when you need it. If you are doing a mortgage, you may need to put in conventional heating, generally the least cost to install is electric baseboard

 

[NSMaple1]

Mini-splits are increasingly being used as the only heat source in some new construction here.

 

[frenchy85]

The mini-splits are looking appealing for back up. Has anyone ever installed their own mini-split? I'm a carpenter with a well rounded background in electrical and plumbing and wondering if I could do it myself. Does anyone know of wood stove that is able to heat DHW?

 

[Mustang71]

As far as mini splits I've installed a few...a lot of them... if you have a vacuum pump and guages you can do it your self. Don't cheap out, get a Mitsubishi. We have had a lot of problems with LG.

 

[VW Splitter]

A small free standing stove will easily heat your house. Having the fire inside the house is more efficient. We have a free standing wood stove in the den on the garage end of the house. It stays warmer in that end of the house and cooler in the bed rooms. We like it that way. We regulate the heat in the bed room by how much we open the bedroom door. Think hard about how you are going to get wood to the stove. It can be messy. We bring wood into the house in a 3' sq box with a pallet jack, park it in the garage next to the den wall. Next to the stove in the den, we have a pass thru to reach into the 3' Sq box in the garage. all the mess stays at the stove. HOOK UP YOUR DOMESTIC HOT WATER TO YOUR STOVE. You will save $ by heating your water also!

 

[frenchy85]

I don't have those kind of tools so I'll probably just have HVAC guy do it.

I'm fully of aware the possible mess and dirtiness of wood. My parents have heated with wood and coal since day one. I like the pallet jack idea. How do you hook your DHW to your stove?

 

[anlrolfe]

Convection. Cold bottom inlet, top hot outlet...
not sure how many stoves are made with heat coils imbedded. There are kits.

 

[peakbagger]

I don't have those kind of tools so I'll probably just have HVAC guy do it.

There is an alternative to a full DIY install. The cost for 12K Btu unit online is around $1,700 for Mitsubishi cold climate heat pump with a high COP. Mitsubishi only sells through distributors and warranty claims are only handled by dealers. Some dealers do sell on line on Ebay but beyond replacing a DOA units you are potentially in trouble if it stops running after 6 months. Local dealers may service it but you are most likely paying it outside the warranty as they didn't sell the unit. If you go with a local dealer they will probably charge you $2,000 bucks to install not including running the electrical service. Effectively they are making enough money that on the rare chance that an outdoor unit breaks down they can just swap in a new one. The vast majority of the install is basic DIY skills, so the option is call around and find an HVAC guy that will do the tricky stuff for you and do the rest including buying the unit. Ideally he should be a dealer but talk to any tech and they will tell you that the vast majority of service calls are not covered by the warranty. The usual service call is physical abuse of the outdoor unit or tubing. Think kids with basketball or someone backing into it. If the outdoor unit case is damaged its likely the tech will replace the entire unit and charge you a premium. If the tubing is damaged there is chance that it just lost its charge and you may luck out with the tech recharging it. Its rare the indoor units have issues except that in dusty homes with pets they can get plugged up and in some cases the coils can get mouldy.

Mounting the indoor unit requires locating studs and screwing a mounting plate to the wall. The unit than hangs off the mounting plate and held in place by couple of screws. You need to drill a hole though the wall to the outside to run the control wires and the two copper refrigerant tubes. You can buy a wall sleeve to line the hole from supplyhouse.com (as well as other specialty pieces). The tubing and control cable is normally run down the siding in vinyl "gutter"that snaps over a faceplate that is mounted on the wall. The outdoor unit has to be hung off wall brackets far enough off the ground that snow can not cover it. Ideally you want the unit on the lee side of the building so snow doesn't blow in the coils and make sure that nothing drips down on the unit. (I have small pitched roof with overhangs over mine to keep snow and any drips off mine). The power feed is 240 volts AC, just install a dual pole breaker and run standard 12/2 romex over to the local disconnect box which is available at Home Depot or Lowes, its just a box with unfused switch to kill the power to the minisplit for service and has to be within sight of the minisplit. The minisplit bolts to the wall brackets via vibration isolators. The wiring is easy, 12/2 to the junction box on the outdoor unit and a smaller gauge 3 conductor wire goes between the outdoor unit and the indoor unit. You also need to install a plastic drain line from the indoor unit to the ground outdoors but hold off as its easier to bundle it in with the copper tubing.

At this point call the tech and hand him the tubing or have him supply it. You can buy preflared tubing kits but most techs cut off the preflares and put their own on. They then will pump the unit down with a vacuum pump check for leaks and then flush the lines with an inert gas. They will then pump the unit down again and let it set for awhile to see if there are any leaks, its supposed to be overnight but most techs are on the clock so they don't wait very long. They then open a valve in the unit and the gas stored in the outside unit flows into the indoor unit from the outdoor unit. From there they turn the unit on and sees if it gets cold. Unless the tech is really dogging it, it takes them less than two hours. I think I paid $200 for the last one I did. Including the tubing and miscellaneous bits my all in was around $2,000 and the best price I could get installed was $3,700. Knock on wood one of mine (an AC only unit) has run for 10 years and the other cold source unit has been running 5 years). You do want to be careful as there are some fly by night outfits that skip steps and take their chances on purging.

Do note, the Mitsubishi and Fujisu cold climate units have a very good reputation. IMO the Daikin's are a step lower. I went with a known brand Mitsubishi , it cost a few more bucks but their reputations in this climate are very good.

Another fairly new option is air to water heat pump. It looks like an minispliut but heat or cools water (or glycol) so the refrigerant stays outside in the outdoor unit. No need to bring in a tech to install as its like refrigerator, already charged and ready to go. Its fairly new to the US. This company has been testing different brands for a couple of years and has this 24K unit available. http://www.americansolartechnics.com/products/space-heat-pumps/ It could be used to run low temperature baseboards and for AC would need an air handler.

 

[Mustang71]

Now with all that being said. I can install one in a day on an existing house. A new build would be real easy. Have the electrician run the wire outside the contrl wire gets pulled with the lineset. Put blocking in the wall before they drywall that way it's easy to mount the indoor unit. Have a plan and it will be easy.

As far as price yes the Mitsubishi is expensive. The LG is much cheaper but we stopped selling those because we had so many problems with them.

 

[frenchy85]

Thank you for the good write up. I'll definitely keep that in with the mini-split. And will go with a Mitsubishi.

What kind of stove would you recommend? What add on for the hot water coil?

 

[MountainHigh]

Wood stove WITH hot water coil is scarce,unless you do it yourself. In England they sell wood stoves with radiator/boilers on the back, but insurance over here won't cover them.

I'm all ears and eyes if someone has something available?

If you decide to forgo the coil, I'd choose a medium sized catalytic converter wood stove that will chug along on low heat for 20 hour burn times, something like the Blaze King Princess model.

https://www.blazeking.com/EN/wood-princess.html

Cat stoves don't need to be run as hot as normal EPA stoves to maintain a secondary burn, so even though the specs might look higher than you need, it's the LONG burn times on low that should work well in your small space. They also have some smaller cat stoves worth looking at if you think the Princess is too large for your space.

FWIW, I definitely would not cut into a Cat stove to mount my own water heater coil. IMHO, that would mess with their burn dynamics and ruin the stove.

 

[VW Splitter]

I don't have those kind of tools so I'll probably just have HVAC guy do it.

I'm fully of aware the possible mess and dirtiness of wood. My parents have heated with wood and coal since day one. I like the pallet jack idea. How do you hook your DHW to your stove?

I built another side on the right side of the stove, 1 1/2" wide with a 60' coil of 1/2' copper tubing in it, with both ends of the copper stubbed down into my crawl space. In the crawl space is a 50 gal water storage tank, and a pump to circulate the water. I have a thermostat near the wood stove that turns on the pump to circulate the water thru the copper tubing when the stove is hot. Water heats up in the storage tank. When we need hot water, It draws it out of the storage tank, then thru a large electric instant hot water heater. The water in the storage tank, in the winter stays between 100 to 130 degrees. The instant hot water heater will heat it to 130 degrees before we get it. In the summer, with no fire we are still drawing out of the storage tank. The instant hot is on it's own in the summer. will heat it to 130 degrees before we get it. In the summer, with no fire we are still drawing out of the storage tank. The instant hot is on it's own in the summer.

 

[VW Splitter]

here is a link to a thread about if I have done it correctly.
https://www.arboristsite.com/community/forums/firewood-heating-and-wood-burning-equipment.55/
That didn't work for me.

 

[Marshy]

So right now I'm leaning towards using a stove in the basement. What you guys use for a flue? Double wall pipe or a traditional masonry flue?

Save yourself the hassle and get either class A (double wall or also called triple wall) chimney pipe, or build a masonry chimney and install an insulated stainless liner. Having a well insulated chimney will ensure trouble free burning for a long long time. The insulated chimneys will give you a good draft in the warmer months and also prevent creosote buildup on the coldest days. If your flue gas loses heat the draft suffers and can lead to creosote.

 

[frenchy85]

Yeah I after pricing the double wall it's kind of a no brainer over a traditional flue. It's better and safer (I think) over a masonry flue.

 

[MountainHigh]

whatever type of chimney you go with, the key to a warmer flue--less creosote--and better draft, is to have the chimney in the centre of the home.

No advantage to using a brick chimney UNLESS you can have full contact with that now mandated steel pipe directly to the passive heat absorption/heat storage of masonry, hence my preference to try to meet todays wood stove regulations, is to look at placing a single wall steel pipe inside brick/tile flue with concrete pour around the length of the pipe - but beware, that still might not fly with inspectors.

Around my area, all new wood stove installations now require steel flue so the days of having large passive heat from thermal mass chimney are numbered. That said, I wiil continue to look at new home builders in sympathy as they know not the joys of thermal mass heating comfort.

It will be a cold day in hell before I will give up my potent thermal mass tile lined chimney for a miserable and unsightly piece of pipe that many feel compelled to try to hide behind fake stonework from a big box store

 

[frenchy85]

That's the one thing about double wall I do not like.......is the looks. I still prefer the look of a traditional brick and mortar flue. I may just run the flue bare now then cover it up with a more traditional flue later. I've always wanted to try and lay up my own flue.

I'm not sure I'll be able to have the flue in the middle of the house (even though I know it's better) due to the upstairs lay out. But I'll run it past the drafter and see what he says.