We have an aprox. 700 sq ft cabin, single story, low ceilings in WNY. The only heat source is a Summer Heat Madison stove, which is great when we are there. The problem comes in with having to drain the water lines and blow out drains and add antifreeze when not there during periods when freezing is possible. We are considering a mini split system just to keep temps above freezing to avoid the plumbing shut downs. We would get alot more use from the place if we could run out for an overnight or weekend without having to open and close the plumbing system. Anyone have thoughts on the practicality of this type of set up , or a better alternative ?
Mini split for cabin ?
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I havent done it but I hiked with a guy with condo in the northern NH (Twin Mountain NH). He had kept the place around 50 degrees during the week and then turned it up when he got there. He did comment that it took quite awhile for it to warm up.
The big issue is that mini splits get very inefficient as the temp drops. Yes some claim to be able to run down to -12 F and maybe put out rated output but they are running no more efficient than a electric heater. My guess is you still will want some electric baseboard with the thermostat set real low and use the minisplit for primary heat.
The big issue is that mini splits get very inefficient as the temp drops. Yes some claim to be able to run down to -12 F and maybe put out rated output but they are running no more efficient than a electric heater. My guess is you still will want some electric baseboard with the thermostat set real low and use the minisplit for primary heat.
I worry about power outages with electric heat and an unoccupied building. Some areas experience many less outages than others, so not sure how risky that is in WNY.
To Peakbagger's point, some are better than others at extreme low temp heat. Even if it DOES have to switch to resistance heat in low outdoor temps, as long as it has that ability, no need for baseboards. And trying to integrate baseboard into an existing place? I think it'd be easier to go with something like a Cadet ComPak in-wall heater if you do need some resistive heat source.
To Peakbagger's point, some are better than others at extreme low temp heat. Even if it DOES have to switch to resistance heat in low outdoor temps, as long as it has that ability, no need for baseboards. And trying to integrate baseboard into an existing place? I think it'd be easier to go with something like a Cadet ComPak in-wall heater if you do need some resistive heat source.
An option that used to be popular is vented kerosene heater. They are very efficient and do not take up much room (but do need a fuel tank). They run on on Kerosene of low sulfur #1 or diesel. Monitors were the big brand but they are no longer built but Toyostove makes them. They are popular as backups to minicplits in very cold climates like Maine.
Mini splits are commonly used for this exact purpose. Many brands even have a freeze protection setting that will maintain a low temperature like 50 degrees. In that setting they will run just the fan periodically and sample the air temp and heat as needed. With such a low load it would run extremely efficient.
It gets pretty cold in WNY. What part of WNY? Is there any insulation on the cabin? There are plenty of units that can heat to some pretty extreme temps like-22. There will be a huge difference in heating an insulated cabin compared to one with no drywall and just exterior sheathing. It shouldn't be to hard to get a rough heat loss number for a small cabin. You would really need one to get the minisplit sizing right.
Bad LP
Minister of Fire
The walls are insulated with pink fiberglass batting, not sure about the roof. Walls are finished either with drywall or paneling. The camp is in Allegany County at about 1800 ft. Temps seldom go sub zero.
Why not replumb the cabin to drain with gravity? If the water isn't there, it won't freeze. It takes only a few minutes to throw a few ball valves and drain my cabin. Then it's a matter of pouring antifreeze down the drains.
Yes. Our friends have a propane stove that has battery backup for the igniter for this reason. There are other stoves that have a standing pilot.
CaptSpiff
Minister of Fire
To the OP, I had similar concerns for a Pocono PA cabin about 15 years ago. All electric baseboard, fully insulated 1100 sq ft, over a block wall basement. Built to drain, we had the departure process down to about 15 minutes (drain lines & antifreeze traps).
Noticed on a few winter visits that the basement got below freezing, and with the electric hot water heater in the basement I got nervous. Decided to stud out the basement walls and hung 3.5 inch batts all around. Also bought 150' of Ray-Chem heat trace cable. Traced the hot & cold the entire runs and put the foam noodle pipe insulation over that. Basement never dropped below 35 after that.
Since then I added a portable oil filled radiator (about $45 at Walmart), with a heavy duty outlet timer, to the basement. I keep the setting on low (600 Watts) and run it about 12 hrs daily in the winter. Keeps the basement toasty in the mid 40's on the coldest day, and low 50's most normal winter days. At about 12 cents a kwh, it costs about 88 cents a day, or about $26 a month.
Lately I'm also looking into the mini-splits for the living area upstairs. Haven't found any good info on maintaining low temp operation (ie 50degF when we're gone). Last I looked a few years back the low inside temp was limited to about 60 degF minimum. Maybe they're better by now, those were not the super low outside temp models.
Brian26, you seem to have read all the manuals. Have you any recommendations of models that cover both below zero outside temperature usability and with inside set-back temps into the 50's?
Noticed on a few winter visits that the basement got below freezing, and with the electric hot water heater in the basement I got nervous. Decided to stud out the basement walls and hung 3.5 inch batts all around. Also bought 150' of Ray-Chem heat trace cable. Traced the hot & cold the entire runs and put the foam noodle pipe insulation over that. Basement never dropped below 35 after that.
Since then I added a portable oil filled radiator (about $45 at Walmart), with a heavy duty outlet timer, to the basement. I keep the setting on low (600 Watts) and run it about 12 hrs daily in the winter. Keeps the basement toasty in the mid 40's on the coldest day, and low 50's most normal winter days. At about 12 cents a kwh, it costs about 88 cents a day, or about $26 a month.
Lately I'm also looking into the mini-splits for the living area upstairs. Haven't found any good info on maintaining low temp operation (ie 50degF when we're gone). Last I looked a few years back the low inside temp was limited to about 60 degF minimum. Maybe they're better by now, those were not the super low outside temp models.
Brian26, you seem to have read all the manuals. Have you any recommendations of models that cover both below zero outside temperature usability and with inside set-back temps into the 50's?
My cabin is similar size, and also built to drain.
I have a drain for the hot, a drain for the cold, and the water heater. Its all in the same place so I open the valves to bleed the system and open the faucets in the kitchen and bathroom to eliminate the vacuum. Then I pour in the antifreeze in the toilet and traps. It doesn't take long.
I plumbed it in pex for freeze protection just incase its needed too.
I have a drain for the hot, a drain for the cold, and the water heater. Its all in the same place so I open the valves to bleed the system and open the faucets in the kitchen and bathroom to eliminate the vacuum. Then I pour in the antifreeze in the toilet and traps. It doesn't take long.
I plumbed it in pex for freeze protection just incase its needed too.
Some units like my Midea and Gree have a setting called freeze protection that claims it will maintain 47 degrees. Most of the Chinese units have this feature including the Mr Cool units.
The big names like Mitsubishi, Fujitsu, Diakin limit the low temperature setpoint to 60-62 and they claim its because of the defrost cycle.
I read this was Mitsubishi's response below.
With a setpoint lower than 60 there may not be enough heat in the space to completely defrost the outdoor coil in lower ambient situations. The limitation is to prevent unsafe operation under certain conditions.
My shutdown process takes about an hour, with the most of it being draining the hot water tank. I do use a air compressor and speed things along with a few psi of pressure. The camp was not plumbed for easy draining that's for sure. I have a surface well with a jet pump inside the water closet. Not the conventional set up with the pump at the bottom of a deep well. We have a UV light set up as well as a particulate filter, still only use the water for bathing and flushing, not cooking or drinking just out of an abundance of caution. Amazing how far a 5 gal cooler of fresh water will go.
Cheep to buy and easy to install is a few pieces of electric baseboard. You do need power, but nothing more reliable. I would redo the water lines to gravity drain. I open faucets and drain to the basement in minutes.
We have a camp in Maine about the same size as yours that we occasionally use in winter . It has a woodstove as a sole source of heat other than a small electric heater with fan . I agree with NateR , I would not depend on any electric device or control to keep a space protected from freezing . We also drain water lines and add antifreeze in the late Fall for the upcoming winter. I would also suggest as others have , to look at gas direct vent heaters with a pilot ignition . We have lived at our camp from May till October for over 20 years . We don't have a well but do have a septic system and leach field . We also bring in fresh water for cooking and drinking ( 5 gallons does go a long ways ). We pump water from a near by pond and filter it to use for toilets ,cleaning, showering etc . In the winter we bring fresh water and drill a hole in the ice to get water to flush the toilet when needed . The toilet is a 1.6 gallon unit so it doesn't take much. When leaving I remove water from the toilet bowl with a kids water squirt tube ( available at a Dollar store for $1 and it works great for this purpose),then just pour antifreeze back in the trap . It works for us but I know folks have different comfort levels and needs ............
Bob
Bob
There is a remote cabin with wood heat near me. Its used by groups on weekends and is only wood heated on weekend. They have a normally open solenoid valve that drains the water system that is closed when the power is turned on. It has an outhouse so they dont have to deal with a toilet which is not readily drain-able.
