Back-up/supplemental heat

it depends on the exact model of baseboard but most permanent baseboard electric heat has an accessory thermostat that can be installed in the junction box. usually they are installed with the power passing through a wall box with a thermostat but most can have a thermostat directly on the baseboard unit.

i am really far more concerned about the 30 cent receptacle that is push backwired than the crimp on to the cord. if it is made with good tooling the crimp connection is fine.

they usually use 16 awg hpn for the cord and use the 90c rating of the cord to get the needed ampacity for the space heater while the receptacle is usually required to be considered 60c by various decrees in the code so that is kind of a problem (although the receptacles are usually actually rated 75 c or 90c by the manufacturer). the temp you have to use for the ampacity calculations is the lowest of the terminations of that wire.

20a general purpose receptacle circuits are not required to have 20 a receptacles unless there is a single receptacle on the circuit. if i remember right the terminals and bridging tab on 15 a receptacle are rated for 20a specifically for this reason although as of around 20 years ago you are no longer allowed to bridge 20a branch circuits through a device.

the only time you need a 20 a receptacle is if you have utilization equipment that uses over 1500w and has a 5-20p or 2-20p plug.

there is nothing that prohibits you from using a 5-20r on a 20 a circuit but in most cases they aren't required. i suspect that other than the shape of one of the contacts, there is little difference between a spec grad 5-15r and 5-20r.

No need to have the HA worry about them, just set their internal thermostat lower than the heating thermostat. One less point of failure (I'm suspicious of HA), and only the places that need heat get it.

Correct. Independent control, so any issues with the HA won't cause a total no-heat failure.

@ColdHouse said "The only problem is the Great Room of my house, which needs some extra BTU's has a wood burning fireplace."

That's not a problem, it's an opportunity. A wood burning fireplace is (1) a waste of space when not in use, and (2) a waste of heat when in use, as most of the heat goes up the chimney.

If this were my house, I'd put a stainless steel liner in the chimney and install a Jotul Lillehammer or similar gas stove with a standing pilot and a millivolt thermostat (no batteries anywhere). A freestanding stove radiates more heat into the room and loses less heat up the chimney than an insert. And with a standing pilot, the stove works the same way a gas water heater does in many people's basement. Water heaters with standing pilots are often left unattended for years.

Light the pilot, set the milivolt thermostat to 55 or 60 for backup heat, and you're done. Or if you're home and want to use the room, turn the thermostat up to 68 and enjoy the fire.

Oh I agree. And in fact the properties my daughter cares for do all have remote monitoring — which notifies her if it senses a problem. It's part of the contracts. That said, it doesn't always work… and, if the person notified happens to be in Florida or the Bahamas or somewuch, it just causes concern but doesn't solve anything.

A lot of great advice here. I use most of them for a second home.

When I lost faith in the safety of our gas furnace , I ran to Lowes and bought four oil fill radiators. They did a remarkable job keeping an 900sq ft ranch home comfortable. We never left them on when house was unoccupied. But before that, we never left furnace on either. It was oversized and expensive. When we leave, we closed main water valve and drained everything and then add RV anti freeze to toilets and sink traps. I also ran a circuit for a twelve foot heat trace for the pipe in front of and behind main water valve, insulated with fiberglass. We did replace the furnace with a 90%efficient Rheem furnace and installed wifi and a nest so in addition to all the above, the nest will turn furnace on if the inside of house drops to 45. This was a twenty year evolution. The only change is we no longer use antifreeze. we still drain the house in case ice interupts electrical power.

Never had a problem with temps dropping into single digits at night . I’d say 99% fool proof; 1% luck as I knock on wood

I have about made a living advising folks to not “change” heat but to add to what you have. In your circumstance a Rinnai Energysaver direct vent wall furnace is the best option for that addition. Quiet, cool to the touch, simple install without disruptive venting and a nice feature set. In addition they are about bullet proof. Another nice feature of the Energysavers in the low electric consumption. The EX22 takes a between 33 & 55 watts so can run off an appropriate battery or small generator in outages. The larger 38 model is about double that. Vent clearance is 9” to a door or window. As such I always install mine below a window as they are generally difficult to decorate under and open into the room. I have had an Energysaver since ‘92 in all of my homes. Living room, basement, garage, shop and have been well served by all of them.

As well, you are getting good advise on trying to get more out of your current system here, as is typical. FYI, should you choose to upgrade your Fujitsu’s, it is not necessary to go to Mitsu. Fujitsu’s do everything that Mitsu’s do. Mini-splits are great but you really have to understand the capacities of the individual units. I think that change would be your worst alternative.

What you describe is not unusual in a space with lots of glass. I have a Florida room in one house and decreased the PEX spacing along the three exterior walls when pouring the concrete for the final limestone floor. You always do this if there is a patio door or larger glass area — The decreased spacing increases the BTU's in that location. It's not huge but you can feel it. I even did an additional PEX loop that's on a separate zone piped off the same manifold that feeds the panel radiators — gives much hotter water to that loop and can flood the area with a band of heat.

Ideally, You want to figure out the heat load on the space. This will give you the actual BTU's needs. My guess you may get a decent idea just playing with the space heaters — since you know the BTU output.

The nice thing about radiant is — silence. Most space heaters are loud. That's my issue with those hydronic kick space heaters or even the sealed combustion cabinet heaters — they make a lot of noise. I use an empire sealed combustion unit in one of the garage spaces. They are easy to install since they pipe right through the outside wall behind th unit.

Unless I missed the description. What type of floor ? Is there any space under the room — crawl or basement for any additional equipment? Do the windows go to the floor ?

Money solves many problems. Wrapping the room or doing strategic placement of common electric baseboard is always going to be the cheapest way to get lots of BTU's into a space. Just the most expensive way to make heat. My power in PA is over $.20 KW. That adds up quick. Still could be the answer depending on how much you need and how often it has to be used. It's math. Spending $15k more for another solution buys a lot of KW's.

The Florida room house also has panel radiators that are controlled through a boiler with outdoor reset and constant recirculation. I oversized the panels to work with 150 f water vs the typical 180 f. That only works if you have the space — doing them with 130 f would most likely be a problem. The other solution would be some form of baseboard. I have used various Runtal units and wrapped spaces under windows with the two tube units — it gets expensive and they have low output. That's what you have figure out that make up number.

Another nice thing about radiant in a space with tall ceilings — lower amount of wasted heat. w/ forced air and very high ceilings you need a ceiling fan to bring down all that hot air that quickly goes to the top.

IMO — don't discount mini splits. I love my Mitsubishi hyper heats — again it's math. How much heat do you need and at what outside temp. Mine work great — but my norm cold is very low single digits. If you have the space they make ducted units — they also make a floor unit. Remember you are not heating the space — your are adding to it. Properly positioned you just want to flood the area with warm air.

My project of a few years ago was a church conversion and we could only get ductwork into about 75% of the space — the whole thing is radiant heat. I used mini splits in some areas and the ducted system has both a heat pump and furnace. This house is also in PA and Propane — the heat pump always wins the cost game with propane. We use the heat pumps in the shoulder season and turn the radiant on when it stays cold. This is a house we only use part time and the radiant maintains a mid 60 temp and we use the heat pumps to bring it up when are going to be there.

Do you have Internet at the house ? That's the way we monitor our vacation homes and there are many ways to manage the temp control of secondary heaters. They make plugs that will turn on a heater when the temp drops and you can get internet switches/ outlets/ even plug in switch blocks to turn on a 15amp load based on washed temp. It's also typically easy to have ways to drain odd pipes to winterize — it takes a long time for the core parts of a building to cool.