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What would you do?

kenorakq | Posted in General Questions on

Forgive me for the vague title and the long post but I am lost in possibilities… all expensive!

Oh and its complicated because I am forced into a decision NOW that will heat my 850 sq ft house AND be adequate to heat in a year (or two) when I add 1000 sq ft. The math gets fuzzier when I tell you the plan is to add 4 inches of EPS to ALL the exterior walls (including existing) and 6 inches under the NEW basement concrete).

No one here (Canukistan) is able or willing to do a manual J to size a unit for a two fold job…

I live in Kenora Ontario Canada (zone 7);

No NG available, currently using forced air OIL furnace (Lennox says its 80% eff).

Insurance company says get rid of the single walled tank: replace with double wall NOW. Local prices are about $4500 to supply and install the tank alone!

My Energy choices are..

Stay… with OIL: (I hate OIL!) its currently 90 cents a liter (it hit $1.30 a few years ago and will again). Pay the $4500 for the new tank.

Switch…. to Forced air PROPANE: its currently 60 cents a liter, Pay $8000 for installation of modulating furnace.

Switch… to forced air ELECTRIC: its currently 21 cents a DELIVERED KW (I know the HydoONE propaganda says its 11 cents BUT I have to add in DELIVERY, ADMIN,TAXES and a few FU fees). Pay $7500 for install.

All the prices in Kenora are higher than the closest big city (Winnipeg, Manitoba 230 km west). MOST of the contractors from Winnipeg will NOT do work in Kenora leaving me stuck paying the local rates.

I am going to start the renovation either next spring or spring 2018: I am hung up by finances and these prices are making it worse.

My hope and goal is to use the NEW HEATING SYSTEM (whatever it turns out to be) as BACK-UP heat to a pair of mini-splits. It gets cold here, well below the lower cut off limit of any current mini-split so for a few months (say mid Dec to Mid Feb) I will need the NEW system to provide primary heat.

I told you it was complicated… and NO the insurance company (current one and I’ve looked elsewhere) will not let me get through this winter with the single walled oil tank.

I need to make an intelligent decision about which way to proceed but am lost…so many factors to consider.

What would you do if you were me and why…. (money is an issue for me).

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Replies

  1. bobhol | | #1

    Hi Tim...I live in the Peterborough area and just finished a new build of 1900 sq. ft. I have 5 inches of EPS over 2by 6 blown in fiberglass walls ,r70 ceiling ,slab on grade I heat with 2 Fujitsu mini splits XLT .Even though last year was a mild winter there was a weekend of -30 weather and the mini splits kept up quite handily.I have baseboards as a back up and have never turned them on ....regards Bob

  2. RMaglad | | #2

    Can you do something about that heat trace line? It's costing you close to $600/yr, using your average 21c/kwh rate (.75x24hrx30dx5mo x $.21/kwh

    Maybe rent a mini ex, relay the line with some insulation, and only heat the entry point. (i understand this may not be possible if you are on rock up in the sheild, but it might be worth the consideration).

    If you addtion is in fact only a year or two away, the smart thing to do might be to get a few cheap baseboards and run them. Likely less than 1000 total install, programmable thermostat to offset peak times.

    Once you build the new addition, get the whole house looked at as one piece?

  3. kenorakq | | #3

    Hi Ryan, yes I know that heat line is a killer... the cable is already insulated and run about a ft under cover...mind you that's just fancy talk for piled rocks over granite. I am considering a drain back system that uses only about 12 ft of heat trace instead of 110 ft and its from your part of the world

    http://www.cottagewatersupply.com/winter-water-systems/

    I called them but the price seems pretty high ($2500ish)... mind you that four years worth of running the heat trace line so its something on my horizon.... have you heard of them?

  4. GBA Editor
    Martin Holladay | | #4

    Tim,
    If you get a Fujitsu or Mitsubishi ductless minisplit with good cold-weather specs, my guess is that the minisplit will satisfy most of your heating load.

    A simple wall-mounted electric resistance heater (or two) should get you through the winter.

    Any chance that your local electric utility offers net-metering agreements for PV systems?

  5. kenorakq | | #5

    Thanks for the input Martin, I was hoping you would chime in.
    Q... do you suggest a single mini-split for now with another in the future (for the expansion)?
    As for supplemental heat... baseboards? or ????
    I'll add that I have a conditioned crawlspace (5 ft tall x 850 sq ft) that would need to be heated as well... I guess that brings up a sidebar question... will heating the main floor with either the mini-split or baseboards (or other) keep the basement warm enough to prevent freezing?
    Or would I need a heater down there too?

    Thanks.

  6. kenorakq | | #6

    Also.... I NEED a dead on manual J... I did the best I could with loadcalc and came up with 27000 btu heat load. Any other ideas?
    fwiw

    850 sq ft, 2x6 constr.
    R40 insualtion in attic (I can add R10 or more to the flat part of the roof..thats the western half but the eastern half is cathedral)
    W side...main door Insulated steel) with small window, 24"x 36" window (tripane wood frame)
    N side... 30" x 36" window (tripane) and 30" X 48" window (tripane) and 42" x 48" window (tripane)
    E side... 72" tripane sliding patio door and 120 inch x 60" window (tripane)
    S side... 24" x 60" window (tripane) and 36" x 36" window (tripane)
    all this over a 5' crawlspace that is 18" above grade on W and N sides and 5' on S and E. The crawlspace floor is a rat slab poured over the granite (no insulation under the rat slab. Crawlspace has R20 batts on wall and exposed concrete stub walls (first 12 inches).
    Built in 1998 ish and average construction.

    Does that 27000 heat load look right for the whole place including the crawlspace?

    If so can you or someone recommend the appropriate cold Wx mini-split?

    Thanks again.

  7. kenorakq | | #7

    Thanks for the reply Bob, I think you are well into climate zone 6.. I only wish it was as tropical here as Peterborough :)

    I have considered zone heating with baseboards BUT think that since the ducting already exists for a forced air system that may be my best bet... that is to stay with a forced air system and expand its supply and return ducts into the reno when the time comes...

    This past winter (15-16) was a pleasant one for us as well with nothing colder than about -35c... it did hover around -25c to -30c for a few weeks though :/

    A large and so far unresolved energy hog at my place is the heat trace line for water (I get all my water from the lake and the line draws a constant 750 watts 24/7) from Nov through Mar.

    Can you share the installed price of those mini-splits, I've spoken to the local dealer; he wants $6000 per unit!!!! and will not allow me to purchase and do the grunt install work with him commissioning the units.

  8. kenorakq | | #8

    Bob in Peterborough... this Q is for you (or others with real life cold Wx experience with the mini-splits rated for cold weather ops to -25c)and colder.

    Can you PLEASE tell me which units (inside and out) you are using?...
    More of the story...

    I spoke to two Fujitsu installers this afternoon (found through the Fujitsu website).. there are none in Kenora and the closest are in Winnipeg.

    Both say there is no such thing as a mini-split Fujitsu or otherwise that will put out useful heat at -25c and they (mini-splits) are best suited for air conditioning and supplemental heat to about -12c.

    I was aghast since I know better: at least I think I do.

    When I pursued the second guy a bit further, quoting from the Fujitsu literature indicated that some of their units put out 80% of their rated capacity at -25c he added that wasn't REAL LIFE EXPERIENCE and to expect little heat below -12c.

    OK: I obviously need to know more than the authorized dealers. Can someone help me chose the appropriate unit for my application.

    I might add as a matter of interest that the first dealer was willing to supply and install in Kenora but would charge $7.00 a km.... that is about $10.50 a mile.... at 200 km the service charge is $1400. He didn't quote me a price on a unit.

  9. exeric | | #9

    Tim, I hope advice coming from a resident of California isn't considered verboten here, especially to someone living in zone 7. I think that if you are seriously considering having a backup heating system to existing mini-splits then you are on the right track. A zone 7 climate is no joke and if you lost electricity for any significant amount of time you might be in real trouble. A backup heating system that requires no electricity is a really good idea. A propane system would fill the bill. There are many gas propane systems,(I'm thinking gas fireplaces), that are very aesthetically pleasing depending on how much of a purist you are in getting a fireplace that emulates a real wood burning fireplace. One thing is certain: It will pay for itself in peace of mind the very first time electricity goes out for a significant amount of time. Also there is no monthly exorbitant charge since a large propane tank can be rented for a modest fee and you would only pay for propane is you use it. Not like natural gas utility monthly fees, (if you had it.)

  10. kenorakq | | #10

    Eric, thanks for the reply and yes you are right it gets cold here.

    I will have a wood stove for ambiance and heat (while we are there but will need a back up system (electric resistance of some sort) to take over below -25c when we are not there to stoke the stove.

    I'm considering a propane forced air furnace (see orig post: its BIG BUCKS) as backup (the duct work is already on the existing side). Problem there is getting a furnace that is not too big for the existing but adequate for the expansion.

  11. exeric | | #11

    Tim,
    I'm seeing a potential conflict with having two mini-splits and a forced air propane heating system in combination. Mini-splits are generally used as zone heaters. Forced air ducted heating systems generally are not considered zone heaters depending on how far the ducting reaches. I think it might be a conceptual conflict if you are defining the forced air system as a "backup" to the mini-splits. It would probably be helpful to think of your house as being a zoned heating system after it is completed. This would also work better with the stepwise completion of your house so that it has adequate but not redundant heating capabilities with the addition you are planning. How you do that would of course be up to you.

  12. bobhol | | #12

    Unless you live with a mini split ,most people including installers doubt they can do the job .I was surprised and impressed with the amount of heat they gave out at minus 20 and lower temperatures. I have the 15RLS2H unit with the XLTH(extra low temperature heating) series.I have seen they can heat my house at these temperatures.I have baseboard heaters as backup but have never used them .I also have a direct vent propane fireplace that I used a few times just to make sure it worked,but it was never needed.My experience has been that most installers are not aware of the Fujitsu and Mitsubishi features that pertain to heat in the mini-splits.They are not up on the latest technology....Bob

  13. kenorakq | | #13

    Well.. thanks to another poster I discovered CoolCalc and have successfully run several Manual J calculations on my home.
    Looks like the heat load is about 36000 btu. This seems believable and about 55% of the rule of thumb sizing I was getting from local contractors.
    Since I am forced to abandon my oil furnace (not a bad thing.. just bad timing) and the other alternatives are prohibitively expensive I decided to kill two birds (well injure them at best) with one stone..
    Since I need primary heat now and back-up heat in the future I will be putting baseboard heaters in the house.
    I will be removing the oil furnace but leaving the duct work (its all in the conditioned crawlspace).
    Anyone have thoughts on whether I should RIGHT SIZE the baseboards for the load or add a safety factor.. say a 1250 or 1500 watt heater when a 1000 watt is all that is needed?
    Is there and energy hit for going bigger? The price difference between each size seems pretty small. Recommendations regarding best/worst baseboard manufacturers?
    The local HD had Dimplex units.
    Lastly... two 2000 watt baseboards in the crawlspace or four 1000 units... is there a reason to go one way or the other... its big one open room.

    Thanks.

  14. GBA Editor
    Martin Holladay | | #14

    Tim,
    I'm in favor of right-sizing your electric baseboard units. Talk to an electrician -- don't forget that oversized baseboard units may require a higher gauge of cable and an upgraded electrical panel.

  15. Expert Member
    Dana Dorsett | | #15

    You might try PM-ing this guy (on another web forum, who also lives in Kenora Canuckistan) who went through this process a few years ago, who may be able to steer you toward (or away from) local contractors & methods, and give you some real-world local feedback:

    http://www.greenbuildingtalk.com/Forums/tabid/53/afv/topic/aff/14/aft/80016/afpg/1/Default.aspx

    http://www.greenbuildingtalk.com/Forums/tabid/53/aff/13/aft/82119/afv/topic/Default.aspx

    The 99% outside design temp in Kenora is -22F/-30C, which is a few degrees below the temp at which Mitsubishi mini-split may turn itself off, but Fujitsu's xxRLS3H series minisplits will keep on keeping-on no matter how cold it gets.

    If you have at least a half-winter's worth of heating history on this house it's possible to estimate the total heat load based on oil use. It's likely (or at least possible) that your heat load for the 850' of existing house is already within the output range of a Fujitsu 15RLS3H, but if it isn't, a bit of electric baseboard would cover the difference. (The all-in installed cost of a Fujitsu 15RLS3H in my neighborhood is about what they're asking for a double-walled oil tank in your neighborhood!)

    Any baseboard back-up only needs to cover the difference between the mini-split output and the heat load, not the entire heat load. With rooms that are doored-off from the ductless head it'll probably need to cover the entire room load though.

    Do you have some exact wintertime to early-spring fill-up dates and quantities we can look at, to get an actual measurement of the heat load of the house as-is-where is, prior to upgrades?

    For the methodology, see:

    https://www.greenbuildingadvisor.com/blogs/dept/guest-blogs/out-old-new

    It's worth running those numbers as a sanity check on any Manual-J or other load calc, which are often a double-digit percentage higher than measured-reality.

  16. exeric | | #16

    I read Dana's comment. I don't have the experience he has about the Fujitsu 15RLS3H but if he says it then I believe it. And if its sufficient for the existing 850 sq foot structure then that's the way to go I think. One can't ignore anymore the cost of fuel or the cost to the planet of burning fossil fuels, so a minisplit in the whole scheme of things seems like the right decision. It will be "cheaper" in the long run in all senses of the word. It's also always better to have direct routes for movement of warm air rather than ducts because of the losses involved in forcing air through ducts. I would not be concerned about the sunk cost of the existing ducts you have. Just forget about 'em. You will also have less potential air leaks if you block them off.

    As far as the backup I mentioned in a fossil fuel heat source. That was really a backup to electricity loss. Since you already have a wood heater then stick with that and don't use it as part of the overall heating scheme, but use it just for emergency electrical outages. I would just add another Fujitsu when you create the addition. There may be some fine tuning as I'm sure you know that would include baseboard heating. But if you can it would be wise to minimize it because electrical resistance heating is not cheap heat, just a cheap installation.

  17. Expert Member
    Dana Dorsett | | #17

    Don't take a WAG as gospel! It's based on some pretty squishy rules of thumb!

    But the guesstimate method goes a bit like this: From experience, most pretty-tight small-ish 2 x 6 framed houses with a fairly simple shape and decent (not extreme performance) windows would have a heat load to area ratio of about 11-13 BTU/hr per square foot at 0F, at an interior temp of 68F/20C.

    At -22F that becomes (68F - -22F =) 90F heating degrees instead of (68F -0=) 68F heating degrees, and a linear approximation of the load would then be, or (90/68=)~ 1.33x the 0F numbers, which become ~14-17 BTU/hr per square foot of space.

    14 x 850' = 11,900 BTU/hr

    17 x 850'= 14,450 BTU/hr

    The 15RLS3H puts out about 15,000 BTU/hr @ -15F, and an unrated lower but similar amount at -20F. Call it 14,000 BTU/hr @ -22F. (Again, a WAG, not a manufacturer specified output.)

    Even if it's only capable of 13,000 BTU/hr @ -22F that's still 15 BTU/hr per square foot and within the silly WAG heat load guesstimate range.

    If the doored-off rooms have baseboard output equal to the full design load, it's more than likely that a 15RLS3H will cover the bulk of the load, with only modest amounts of baseboard use if the doors are left open.

    A fuel use based heat load calculation would tell just how far off that load estimate is. We have no way of proving the actual output of the 15RLS3H, but it's still putting out something decent & real.

    Another sanity check: A sometimes poster here going by the handle Jin Kazama heats his 60' x 40' (2400') single story house in Quebec with four Fujitsu 9RLS2H minisplits, and has sailed through -30C lows without discomfort. That's 3 tons of mini-split for a 2400' house. From a simple ratio, 3 x 850/2400= 1.1 tons of mini-split. The 15RLS3H is 1.25 tons, and a newer generation with better cold-temp capacity than the older RLS2H series Jin Kazama is using.

    See response #18 here for a brief description of his house & mini-splits:

    https://www.greenbuildingadvisor.com/blogs/dept/qa-spotlight/looking-best-minisplit-option

    I couldn't quickly dig up his report on how well it fared at ~-30F degrees, but that may have been in a private email. IIRC he claimed it was keeping up with the load, but that the temperature of the air coming out of the ductless heads was noticeably tepid compared to the warm breeze they delivered at -20C.

  18. kenorakq | | #18

    Wow, some great information and food for thought... I will do some reading on that Fujitsu unit. Unfortunately we have never stayed full time at the house (yet, we are evolving to that), mostly weekends and holidays, I would estimate 30% of the time the heat is at 70f during the day and 65f at night. While away (70% of the time) its set back to 50f. A winters of oil Nov to Apr is about 800 liters. We always fill the 1100 liter tank in the fall and have about 1/4 tank left in the spring. That is heat only since the HWT is electric.

  19. exeric | | #19

    Dana, as its been implied here before, if the square foot/ btu numbers work for a certain number of
    mini-split units it's often the simplest installation and the lowest energy usage. But the biggest caviat is how open plan the area is for each unit. If one can't make it work for the architectural drawing and the occupant's lifestyle then its kind of moot. But it sure would seem a shame to forego those advantages, especially since Tim has the opportunity to adjust the architectural requirements in the new addition for the advantages that mini-splits otherwise possess. I hope Tim can do it.

  20. kenorakq | | #20

    I just double checked the oil usage its closer to 900 liters for the heating season 15 Oct to 15 Apr, At an average (around here) of $1.00 liter so $900 to heat for the season.
    Can someone help me figure out my electric bill for heating given the above calculations and 20c per delivered KW?
    I'm wondering if there switch to electric will come in "close" to the oil $$$ per season.
    My math is disturbing using even Dana's lower heat loss..
    15k btus x 24 x 30 x .20 = $2160 a month.
    Please tell me I did that wrong!!!!!!

  21. kenorakq | | #21

    I just used the efficiencymaine.com online calculator and input $1000 for oil at $3.70 USG and changed the price per kw to .20 and came up with $1465 as a comparably cost to heat with baseboards. And $417 with a ductless heat pump (their description)... looks like I'd be a fool not to go that route... Minisplit with BB backup.

    If that is right I can live with it... if not please correct me!

  22. kenorakq | | #22

    as an aside... about half the time I try to post something I get a CAPTCHA combo that includes a symbol I don't recognize and can't type in..looks like a backwards 3 with the tail of a G.. I tried the (British) pound symbol but that doesn't work..

    What is it?

  23. kenorakq | | #23

    Dana... re post #15... that guy is me :/

    yes I've been working on this a long time....still not resolved.... but closer :)

  24. Expert Member
    Dana Dorsett | | #24

    So, Tim, didja PM yourself before figuring that out? :-)

    At the high end heating oil runs 140-142,000BTU/gallon, typ- is more like 138-139,000 BTU. Assuming 140K as the number, 900 liters is 238 gallons, or (x 140K =) 33.32 MMBTU (million BTU). Assuming an 85% efficiency burner, that's 0.85 x 33.32= 28.32MMBTU that went into heating the house.

    Assuming the average temp in the house was 55F (50F while away, ~68F average when occupied), let's use 50F as the degree-day base temperature. They're currently having database access issues at http://www.degreedays.net/ , so I'll have to pull a daily base 5F HDD to cover the 15 October through 15 March period to complete the analysis later, once they're back up. Or maybe you can. The methdology is outlined here:

    https://www.greenbuildingadvisor.com/blogs/dept/guest-blogs/out-old-new

    Scroll down to the bold faced header: "You can calculate a building’s heat load in 15 minutes"

    In your case, once you've calculated the BTU per degree-hour constant using base 50F data, multiply that constant by 90F (the difference between 68F and -22F) to come up with a worst-case implied load number. Reality would be more like 80-85 heating-degrees, if it's pretty tight 2x6 /R19 type of construction.

    When it's below -20C don't count on a COP better than 1.5-1.8 for the average efficiency out of a mini-split, but when it's -10C and warmer it'll be at least in the high-2s if sized for the -30C design load, but well into the 3s at 0C and above.

    That squiggly backwards 3 with a tail is one font style for ampersand (" & ").

    https://www.google.com/search?q=ampersand&rlz=1C1LAVE_enUS391&tbm=isch&tbo=u&source=univ&sa=X&ved=0ahUKEwi6h4aa7e7OAhWEmh4KHXjjAm4QsAQIKw&biw=1196&bih=838

  25. Expert Member
    MALCOLM TAYLOR | | #25

    Tim,
    I think that is CAPTCHA's version of &.

  26. user-968917 | | #26

    Is there a way to PM other users on this forum?

    Tim, I am Winnipeg-based but do a lot of building science/home performance work in Kenora area (I also have a place nearby there).

    I'd be happy to help you out on your project or act as a sounding board.

    Gio

  27. kenorakq | | #27

    Good to hear...
    [email protected]
    Thanks
    Tim

  28. Expert Member
    Dana Dorsett | | #28

    degreedays.net is back up...

    Downloading a base 50F daily spreadsheet, from 15 October 2015 through 14April the weather station at Grassy Lake just outside of Kenora logged 5350 HHD50F. (There are several weather stations in the Kenora area to choose from on degreedays.net. I picked one a bit out town figuring it would be a bit cooler there, but you can pick one closer to the actual site if you like- it won't change the results by very much.)

    Over that period the house went through 900 liters of #2, which delivered about 28.32 MMBTU into the heating system (see response #24)

    28.32 MMBTU/5350 HDD= 5293 BTU/.HDD

    In a 24 hour day that would be 221 BTU per degree-hour.

    Assuming a heating cooling balance point as high as 65F, and a design temp of -22F that's 87F heating degrees.

    The implied load is then 87F x 221BTU/F-hr= 19,227 BTU/hr.

    If you assume a heating cooling balance point of 60F (typical for 2x6 framing) that would be 82F heating degrees for an implied load of 82F x 221 BTU/F-hr= 18,122 BTU/hour

    That's really an upper bound- most equipment rated at 85% efficiency doesn't really hit it's marks, and since it's a force hot air system there will be some amount of air-handler driven infiltration adding to the load, etc.

    So, if you figure the 15RLS3 is good for 13,000 BTU/hr @ -22F (guesstimate, not a manufacturer's rated output), and the real load is as high as 19K (which it's at least possible), you have about 6,000 BTU/hr of load to make up, which can be covered by only 1800 watts of baseboard.

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