Ready to ditch my heat pump split system in cold upstate NY

josephny

I sure would appreciate some help solving a problem. I'm not a pro, and know very little compared with you all.

I have a small cottage in upstate NY (zone 4B) that I converted years ago from seasonal use to all-year use.

This involved spray foaming the underside of the roof, the walls and the underside of the floor (cottage is on raised piers).

But, prior to that (and prior to my current level of understanding) we added a room increasing the footprint by 50% that has cathedral ceilings with exposed rafters and no ceiling/roof insulation; it also has 3 exterior walls that are almost entirely glass (the underside of the floor in this section of the cottage has spray form just like the rest of the cottage). This addition is 24'x18'

Total cottage size now (with addition) is 24' x 42' (8' ceilings; 4 or 5 pitch roof).

About 6 years ago I had a heat pump split system (manufacturer: Pioneer) installed. The installer provided 2 outdoor condensers: 1 for the addition connected to a single wall mounted inside unit (36,000btu) ; the other (36,000BTU) for the original area of the cottage with a ceiling cassette unit in the kitchen and each of the 2 bedrooms.

The system has never worked well. The bottom 2' of the entire place is always cold, walking barefoot is completely unpleasant because of the cold, and from December through March it's almost impossible to keep the place at a comfortable temperature. And the electric bills are crazy high (and my rate is about $0.12/Kwh).

A couple of months ago (middle of the Winter) the outdoor unit serving the addition died (puffs of smoke).

I'm ready to ditch the entire system.

I think the problem is the Pioneer was never the right choice because it just can't handle these Winters AND the ceiling cassettes (being 8' from the floor) and single indoor unit at 7' from the floor for the addition is inadequate. There is also the fact that the system dries out the air so much that sleeping is quite uncomfortable.

I have plenty of propane and electric to the cottage.

I was thinking about a combi in the attic providing hot water (hydronic) to wall-mounted radiators. Space inside the cottage just doesn't exist for a boiler. I now have a Rinnai tankless hot water heater in the attic which has been working fine. But, the attic at the peak is only 4' tall.

What can I do?

Any good options?

Thank you.

Mad Dog_2

Add a Combi Heat/hot water and add Panel rads or regular baseboard to supplement the Cassettes.  2 Stage T Stat.  Mad dog

josephny

Mad Dog_2 said:

Add a Combi Heat/hot water and add Panel rads or regular baseboard to supplement the Cassettes.  2 Stage T Stat.  Mad dog

Thanks for the help!

Will I have a problem installing a combi in an attic with 4' height?

Anything I should consider other than aesthetics and maybe ease of running pipes when deciding between panels or baseboard?

psb75

Yikes a building on piers in the north country will always be at a disadvantage. Do your best to STOP air movement underneath the building--i.e. creating an enclosed crawl-space (vapor barrier recommended).
You added 50% to the total sq.ft.-age that has NO ROOF INSULATION!? This is especially disadvantageous. This is like you being outside in the winter with NO hat. And 3 walls with mostly glass? Yet another "strike." Doesn't this total "three strikes"? Then..."you're out"! No wonder the poor heat pump is "sending out smoke signals."

Solid_Fuel_Man

Baet way to insulate the exposed rafters is with foam board on top, 4" of polyiso would be my minimum recommendation. Then strap, plywood and reroof. That way the inside look is maintained and you have decent R value in the ceiling/roof. 

With an open bottom place, you will always have a cold floor. Panel rads will help somewhat, but the floor will always be cold. Only way around it is radiant floor. With spray foam underneath l, you'd likely have to use a sandwich type of radiant panel and then put down new flooring on top. 

What type of flooring do you have now? 

Radiant is the Cadillac, always will be. 

Mad Dog_2

Have a good HVAC tech evaluate the cassette system too  mad Dog 🐕 

Mad Dog_2

As long as it's serviceable, can't freeze and is far enough from combustibles, you do it.  Tried Find A Contractor Feature.  Get a Serious pro ot there to evaluate.  Mad Dog  

Jamie Hall

@Mad Dog_2 is quite right -- at the present state of the art, there is no way that your heat pumps can keep that place -- or, for that matter, any place, insulated or not -- warm in the winter in your climate. No can do. You can still use them in the shoulder seasons -- no harm to that -- but you will need that combi and panel radiators to really do the job.

Don't hesitate! The politics are not in your favour, and you may not be able to install the combi if you wait too long. They say that it will only be new builds that are prohibited, but the devil is in the details and you are not replacing an existing system.

hot_rod

A combi in a 4’ attic? Check the required to clearances, sounds like an unpleasant place and space to work. Is it heated?

keeping the floors warm on a structure like that will be a challenge $$

neilc

You said the air is too dry due to the heating system,
I don't know, it doesn't really work that way,
especially with that spray foam, which should be sealing everything while insulating , , ,
this should be holding in your humidity,

I'm suggesting air leaks, which exchanges super dry winter air, are your issue,
Have you had a blower door test done?

I have found mucho leakage just by running my bath and kitchen exhaust fans, add the clothes dryer,
then bare footing it along all the baseboards, hard floor and carpeted,
caulked/sealed the baseboards to the floor(neatly and meticulously),
with the back of my hand at light switches and outlets, and meticulous chalk and seal the box holes, and box to sheetrock,
interior walls included,
same with ceiling fixtures, ceiling fans, the sheetrock at the bath exhaust fan, and the fan housing
window and door trim, same,

look for air leaks,
my (old) cold drafty house is much more comfortable now, furnasty runs far less now,

pecmsg

Its not the heating system but the design!

Without in floor radiant heat that floor will Always be cooler/colder than the rest of the space.

neilc

oh, and oh,
yeah, stratification with ceiling cassettes is real,
use the swinging air louvres function to stir the room

EBEBRATT-Ed

Unfortunately any air system will not heat a structure like this in cold weather. A lot of glass and cold floors are a big issue as well as the roof insulation.

Guess it depends on how much you occupy the house and your budget and other factors. It will likley cost a lot of $$$$ if you really want this right.

It all depends on how comfortable you want it.

Dave Carpentier

Would it be cost effective to "box in" the structure at and below ground level ?
Im thinking a perimeter trench, maybe 3ft+ deep, and styro insulation vertical and then horizontal to meet the wall at the floor level.
No one likes to give up floor space, but at 1000 sqft maybe a fake closet to hold heating equipment ?

Jamie Hall

On dry air. One of the most common misconceptions out there is that heating "dries" the air. Whatever kind of heating system -- they've all been accused of it.

Nope.

What happens is that cold air, such as the necessary for health air exchange from outside in the winter (2 to 4 air changes per hour is a bare minimum) contains a lot less water vapour than warm air can hold, so when we heat that air, although the amount of water vapour stays the same, the relative humidity drops. And it's relative humidity that we sense as "dry air". The only solution, regardless of heating system used, is to add moisture to the air.

Back in the bad old days, we had radiators, and one simply placed a pan of water on the radiator. Worked like a charm. However, that's not wi-fi enabled and internet connected, so now we get by with fancy humidifiers in the winter time. They work, too, most of the time anyway.

EdTheHeaterMan

Remove all the walls, ceilings, and floors. figure out which direction is north, don't put many windows on that side of the house. If you want lots of glass, put that room on the south side. Have a large overhanging roof to block the summer sun from all that glass, when the sun is lower in the winter the sun will offer solar gain to help heat in the winter.

Until then:

Only bandaid that I can think of until the home is completely rebuilt for a more efficient design. https://www.amazon.com/Woo-Warmer-Carpet-Radiant-Electric/dp/B00XK28ODK?th=1

Big Ed_4

Install a radiant floor would be the best choice . In Europe they hang their wall hung boilers and water heaters in the kitchen .

Jamie Hall

Look. Our OP, @josephny , has a nice little cabin in upstate New York -- which is a rather broad term, but likely not just Westchester County. He likes his cabin, but he'd also like to stay warm in the winter.

Someone conned him into a heat pump. It doesn't work, and won't work. It's too cold outside part of the year.

He doesn't want to rebuild the place.

I agree with @Mad Dog_2 's first post. Add a nice gas fired combi boiler/water heater somewhere convenient (I'm not keen on the attic, but these things aren't that big. Surely somewhere...). Use panel radiators. The cold floor is a problem, but is it insulated underneath? If not, spray foam it. You could also, if it is easily accessible, add radiant tubing powered by the combi, and add insulation underneath that.

TonKa

Keep in mind an improperly designed and implemented hydronic system (whether radiators, radiant floor, baseboard, etc) could heat the place just as poorly as it is now, but differently.

ethicalpaul

I wouldn't have gone with exclusively mini-split in that zone, but the real killer was (like @EBEBRATT-Ed and others said):

we added a room increasing the footprint by 50% that has cathedral ceilings with exposed rafters and no ceiling/roof insulation; it also has 3 exterior walls that are almost entirely glass

3 exterior glass walls (single pane? although it doesn't matter much, glass is an excellent heat conductor), exposed rafters with no insulation, you are in trouble. I'd love to see the heat loss data on that.

Zone 4b, that is extreme cold, that ain't Westchester for sure

Big Ed_4

Heat pumps always had auxiliary heat option . I am not a big fan but to bring to thought , laying out electric radiant mat may be an option .

leonz

josephny said:

I sure would appreciate some help solving a problem. I'm not a pro, and know very little compared with you all.

I have a small cottage in upstate NY (zone 4B) that I converted years ago from seasonal use to all-year use.

This involved spray foaming the underside of the roof, the walls and the underside of the floor (cottage is on raised piers).

But, prior to that (and prior to my current level of understanding) we added a room increasing the footprint by 50% that has cathedral ceilings with exposed rafters and no ceiling/roof insulation; it also has 3 exterior walls that are almost entirely glass (the underside of the floor in this section of the cottage has spray form just like the rest of the cottage). This addition is 24'x18'

Total cottage size now (with addition) is 24' x 42' (8' ceilings; 4 or 5 pitch roof).

About 6 years ago I had a heat pump split system (manufacturer: Pioneer) installed. The installer provided 2 outdoor condensers: 1 for the addition connected to a single wall mounted inside unit (36,000btu) ; the other (36,000BTU) for the original area of the cottage with a ceiling cassette unit in the kitchen and each of the 2 bedrooms.

The system has never worked well. The bottom 2' of the entire place is always cold, walking barefoot is completely unpleasant because of the cold, and from December through March it's almost impossible to keep the place at a comfortable temperature. And the electric bills are crazy high (and my rate is about $0.12/Kwh).

A couple of months ago (middle of the Winter) the outdoor unit serving the addition died (puffs of smoke).

I'm ready to ditch the entire system.

I think the problem is the Pioneer was never the right choice because it just can't handle these Winters AND the ceiling cassettes (being 8' from the floor) and single indoor unit at 7' from the floor for the addition is inadequate. There is also the fact that the system dries out the air so much that sleeping is quite uncomfortable.

I have plenty of propane and electric to the cottage.

I was thinking about a combi in the attic providing hot water (hydronic) to wall-mounted radiators. Space inside the cottage just doesn't exist for a boiler. I now have a Rinnai tankless hot water heater in the attic which has been working fine. But, the attic at the peak is only 4' tall.

What can I do?

Any good options?

Thank you.

=================================================================

Do you have National Grid or NYSEG for an electricity supplier? I am in located in the fingerlakes region.

I will get laughed at, but you can have a coal stoker stove installed in a side wall or a corner with no furniture and heat the entire home with it and be able to place a big pot of water on it to add moisture to the air.

Option 2 would be to have wood pellet stove installed and use that for heat and put a big pot of water on it to add moisture to the air, but you would use twice as much in wood pellets versus a coal stoker stove and the heat transfer would be poorer.

The wood pellet stove would create less ash to deal with and you can use the ash for a garden or plants or just put it in the trash.

The ash from a coal stove can safely be disposed of with your weekly garbage using the bag the coal came in.

Bagged rice coal can be stored outside if needed simply by covering it with a water proof tarp.

Wood pellets should be kept inside to keep them dry. If you have no place to keep the pellets you can place the bagged wood pellets on pallets by stacking 2 pallets high to keep them off the ground and cover them with high quality waterproof tarp.

You can have the wood pellets or bagged coal delivered to you if you want to do it that way or bring home bags pellets or coal in your car.

Robert_25

Greetings. I also live in 4B and happen to have a cottage on an uninsulated concrete slab. You have your work cut out for you if you want your cottage to be comfortable in the dead of winter.

Anything other than radiant heat is not going to be comfortable in that structure (b/c without it the floors will be cold and uncomfortable). The addition with all the glass is going to be a challenge - you need to insulate the ceiling in the addition. I think a product like Uponor Quik Trak could be a good solution to get radiant heat, but you would have to be willing to tear up the floors and everything that goes along with it.

If radiant heat is not an option at this time, have you considered a wood stove? I know burning wood is not for everyone, but sitting in the same room as a woodstove will feel a lot better than having that minisplit blow a cold draft on you.

Mad Dog_2

Where is 4 B?  Is that a DEC designation?  I'm in 1C (Long Island 🏝) if that's the case. Mad Dog

josephny

Thank you all so much for help!

I am in North East Sullivan County. NYSEG territory.

Got it: Piers, and an addition that represents 43% of the footprint of the entire structure and has lots of windows makes for a tough situation.

If I rip off the shingles, can I just put 4" of polyiso on top of the sheathing, screw down 2x4 strapping, put down another layer of sheathing and then shingles on top? I can do that.

Googling shows 4" of poly would be R-23, which would be fantastic.

I think insulating the addition roof and adding a combi in the attic would be great. The attic is part of the conditioned space with spray foam on the rafters.

I looked at some specs online and many common units range from 30-35" in height and then additional clearance above and below for venting and plumbing.

The Rinnai hot water heater I currently have is 26" and it truly just fits (the plumbing fittings sit below the plane of the top of the floor joists of the attic (ceiling rafters of the kitchen). So, I'm worried about it fitting.

I can't imagine my wife agreeing to giving up any of the closets to dedicate to a boiler.

What about building a closet on the outside of the house? Perhaps a 3' wide by 3' deep by 6' high closet, with insulated floor, wall and roof, vented into the house (so the inside of the new closet is part of the conditioned space), dedicated to the boiler?

Air exchanging and the physics of bringing cold air in lowering the RH! Fantastic.

As far as creating an enclosed crawl-space under the house: I have been worried about doing that because of all of the warnings of creating a place for mold to grow. I can put down plastic on the ground and close off the sides with insulated boards, but then the area between the underside of the spray-foamed underside of the house and the plastic covered ground will have no ventilation and any moisture that makes its way in there will stay there.

A wood or pellet or coal stove is not possible because of a lack of space and there regularly 1-3 week periods when no one is at the cottage.

I have wood flooring throughout (except tile in bathroom), and the idea of the huge process of raising the floor by a bunch of inches (kitchen, bathroom, doors, molding, etc.) would be too much to handle.

Thank you all so much!

Mad Dog_2

Whats great about the Tankless/Combis is you can put them almost anywhere, on an outside wall is preferable.  They are so compact, I have put them in Closets...and still have room for some shelves or shoes 👞.   Mad Dog 

josephny

My local supply house is a dealer for IBC, so I'm looking at the SFC199 (hot water modulating 28-199k; heat modulating 20-125k), requires 6" on each side and 2' on the top, bottom and in front for clearances), 33" high, 18" wide, 11" deep. Total space needed would be 7' in height, 30" in width and 3' in depth. But, with expansion tank, air eliminator, fill valve and pump(s)/valve(s), I'm concerned I'll need more space.

Seems like I might have to make the closet much wider (which might be a problem).

HVACNUT

If you jam a boiler in a closet, make sure everything is accessible and serviceable. 

Jamie Hall

josephny said:

My local supply house is a dealer for IBC, so I'm looking at the SFC199 (hot water modulating 28-199k; heat modulating 20-125k), requires 6" on each side and 2' on the top, bottom and in front for clearances), 33" high, 18" wide, 11" deep. Total space needed would be 7' in height, 30" in width and 3' in depth. But, with expansion tank, air eliminator, fill valve and pump(s)/valve(s), I'm concerned I'll need more space.

Seems like I might have to make the closet much wider (which might be a problem).

All that additional stuff -- the expansion tank, pumps, air eliminator, fill valve -- does take up space. But there's no rule it has to be right there next to the boiler. So long as the bits are correctly placed relative to each other, that group of items can be elsewhere -- like in your warm loft space. Just takes a little creative thinking on the part of the installer.

josephny

Jamie Hall said:

josephny said:

My local supply house is a dealer for IBC, so I'm looking at the SFC199 (hot water modulating 28-199k; heat modulating 20-125k), requires 6" on each side and 2' on the top, bottom and in front for clearances), 33" high, 18" wide, 11" deep. Total space needed would be 7' in height, 30" in width and 3' in depth. But, with expansion tank, air eliminator, fill valve and pump(s)/valve(s), I'm concerned I'll need more space.

Seems like I might have to make the closet much wider (which might be a problem).

All that additional stuff -- the expansion tank, pumps, air eliminator, fill valve -- does take up space. But there's no rule it has to be right there next to the boiler. So long as the bits are correctly placed relative to each other, that group of items can be elsewhere -- like in your warm loft space. Just takes a little creative thinking on the part of the installer.

That would indeed make things much more doable. But....

If I'm doing a primary/secondary loop, other than the relative order of the additional items placed on the primary loop, and the distance between "taps" on the primary loop that create a secondary loop, aren't there pipe-length considerations (heat loss/flow rate, internal (to the combi) pump capabilities, etc.)? As you can see, I know juuuust enough to ask silly questions.

I can make the "outdoor closet" 5' wide, so I might be able to fix everything, unless I go crazy with multiple loops).

Jamie Hall

There are piping head loss considerations in the primary loop, but if you don't skimp on pipe sizes they are actually pretty minor (going from 1 inch to inch and a quarter cuts the head loss in half, for instance). If you keep the primary loop piping simple and direct, and your installer does the math right, it won't be a factor. You will want to insulate the primary loop piping if it is of significant length, but that's also not a problem.

And don't go crazy with loops. Keep it simple. I can't see that you would want more than three, even if you do do some radiant floor.

JakeCK

Yes you can put polyiso on the outside of the roof deck, and reroof over it. That is infact a fantastic way to insulate a vaulted ceiling and is quite possibly the safest way.  Honestly if you are willing to do that, do it before the boiler. That will change the size of boiler you need significantly. And you should still look into enclosing the underside of the cabin. Concerns of moisture can be mitigated with some ventilation. That is done all the times with houses that sit on a crawl space. 

Now if you did both of those you could possibly reduce your heat loss by a 1/3rd. And maybe, just maybe it might be comfortable with that heat pump. Honestly it is pretty impressive it is keeping up at all. It's been handed a no win scenario.

Fyi vaulted ceilings, while pretty, are a design/engineering nightmare when it comes to energy performance. So much that needs to go right or is left to chance and so much that can go horribly wrong. 

Edit: thinking this through some more, your uncomfortably low humidity in the winter might actually be saving your bacon. Before you do anything have someone calculate the expected dew points so you can find out what would happen if you started humidifying the house to something a bit more comfortable. Even an uninsulated vaulted ceiling might suddenly start having having moisture issues if you raise the RH.

Solid_Fuel_Man

Insulating with polyiso on top of existing roof decking (I call it a sandwich roof) has been done many times. 

You would be amazed at the reduction in heatload it will make in the summer as well. 

Theoretically, if you add enough foam you can skip the venting, we call it a hot roof. I know some people who have done it woth Structural Insulated Panels (SIP) but I'd always strap and vent. Safest option for snow and ice dams. 

Formerly

If you decide to add PolyIso to your walls/roof, make sure you take into account moisture - Poly will destroy your house if not properly lapped and taped to prevent moisture travel. A great guy to read up on/watch vids on is Joe Lstiburek. He's got many videos regarding how to do this right (as well as a new updated book based on today's building materials) but the video to watch before undertaking any external Iso-usage is this:

https://www.youtube.com/watch?v=Ld8pzIu45F8

jumper

That guy has really researched these topics. Detail work for net zero ambitions seem impractical too me. I prefer Listiburek's older methods of drained and ventilated cavities. Perfect is enemy of good.

JakeCK

Formerly said:

If you decide to add PolyIso to your walls/roof, make sure you take into account moisture - Poly will destroy your house if not properly lapped and taped to prevent moisture travel. A great guy to read up on/watch vids on is Joe Lstiburek. He's got many videos regarding how to do this right (as well as a new updated book based on today's building materials) but the video to watch before undertaking any external Iso-usage is this:

https://www.youtube.com/watch?v=Ld8pzIu45F8

I've watched this before. He's someone I would love the opportunity to sit down with and pick his brain.

Dave Carpentier

For the risk of trapping moisture in an enclosed crawlspace, check a radon vent fan maybe ?
The trick would be to adjust the speed to just quick enough to lower any evap moisture from the ground.
Maybe a humidistat controller ?

Mad Dog_2

S.S.D.S. Sub Surface Depressrization System.  It's of course much easier to do with new construction, but if the crawl space can be accessed, it can be added..  nice DIY project.  Removes dangerous gases in the soil and moisture.  Mad 🐕 Dog 

The Steam Whisperer

I found in my home that by installing a simple sump pit and pump, it dramatically lowered moisture levels in the basement. We no longer have to run a dehumidifier in the summer. This, along with the low E glass storm windows installed on the west side, cut our electrical bill by about a third or more in the summer. We cool the 1500 sq ft main floor and basement for a $90.00 total bill in the worst summer month now. I still need to install the second sump on the opposite end of the basement ( the basement is about 45 feet long). Our soils are heavy clay below the topsoil.

Dave Carpentier

Mad Dog_2 said:

S.S.D.S. Sub Surface Depressrization System

Is that a real term ? Sounds like a reason to add another large to the bill.. lol
But I guess it could indeed suck anything out of the under-slab, including radon but not limited to.

Would an extractor fan like this just end up sucking more humidity out of the ground ?
Maybe there is a balance point of just gently sucking the excess under-floor humid air without creating additional issues.

ChrisJ

ron said:

josephny said:

Ready to ditch my heat pump split system...

given The Biden Regime said reports claiming they were seeking to ban gas stoves was a conspiracy theory, Chuck Schumer went out of his way to chastise those concerned saying, “Nobody is taking away your gas stove.” ... to New York's new law [May 2, 2023] will effectively ban natural gas stoves in most new homes and buildings by as early as 2026 and that “Changing the ways we make and use energy to decrease our reliance on fossil fuels will help ensure a healthier environment for us and our children,” New York Speaker Carl Heastie said in a statement. and Dozens of cities around the United States have adopted or are considering policies that ban or discourage natural gas... [in new buildings]

now before anyone goes all "ugh no politics", i'm stating fact from current news reports, this is happening. And it's also being said - you can believe this or not - that "they" want things to go all electric so "they" can control and turn on and off, in the name of climate and save the erff. We've already seen this with smart thermostats in the recent past, colorado or texas or california, where they "mandated" no AC setting lower than 80° or whatever to alleviate grid problems in times of a heat wave. I do not doubt the same thing will happen in mid winter when the same thing happens on the cold side of the thermometer, and we've also witnessed grid problems currently happening.

So for upstate NY, being rural for a [home] for "good options" I would have a plan C for when Propane (Plan as a fuel becomes expensive or hard to get given the warning signs, given your considering moving off of Plan A (heat pump). A pellet stove does work really well, but I wonder if that fuel will be in the crosshairs as well, and are they reliable/safe (automatic feed) for when you are not there? The old fashioned cast iron wood stove is often hard to beat (when you are there to operate it and keep it going when needed) and when it has a good length of flue inside to capture and put that heat to the inside. Otherwise I think your real question comes down to fuel source that no one wants to admit. And would getting a 275gal or more home heating oil tank be an option? Installing a oil boiler to have either baseboard or steam heat? The controls and safety and readability of that route is proven. Otherwise if such a thought offends because it's going backwards and not progressively forward, then a good option could be wear socks and shoes and a hat indoors and drain your water pipes when it gets cold, I'm being objective here.

You know "they", whoever that is, could set it up to remotely turn natural gas on and off.