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1

I installed a pair of Nest smart thermostats in my house and my energy bills have not changed to a statistically significant level compared to my rather basic programmable thermostat. That is, the amount saved due to using less energy was less noticeable than the amount I saved by switching to a different electricity provider (YMMV, highly dependent on how ...


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Lots of great guidance in other answers, let's apply it to your situation Say you have a completely dumb thermostat, no timer, and you have periods where the home is unoccupied or you don't mind having less heat or AC while sleeping, so there is good opportunity for savings. Say all the arguments in the other answers favor a smart thermostat. The ...


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A smart thermostat is almost guaranteed to reduce your energy usage by 4 to 19%, depending on your climate and HVAC system type. No need for hypotheticals -- there's hard data Given the length of time that smart thermostats have been on the market (the first generation Nest was released in 2011), there have been a number of field studies to verify energy ...


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I don't believe there is a clear answer despite all the theories/guesses that are purported as fact (not here, but elsewhere). So, I default to logical scenarios to better understand. Imagine a tire is filled with compressed air, but has a tiny hole in it. The tire is the house, the air is the heat and the size of the hole is the quality of the house's ...


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One benefit of a programmable (not necessarily smart) thermostat that I recently saw in a youtube video is that you can schedule your heating / cooling to occur while energy rates and demand are lowest - i.e., overheat / overcool your house. For example, cool your house to 65 degrees overnight, and let it gradually warm up throughout the day to 75. Depending ...


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Here is the science-based thermodynamic law that drives all this. Suppose you have 2 spaces, A and B, at different temperatures. Between them, there is some level of thermal insulation. No matter what is true about the insulation, this rule always follows: Thermal transfer is proportional to the difference in temperature. Take any random insulator (green) ...


4

One of the benefits of "smart" systems is you can make more than just time-based adjustments, though it depends on the system. I have an EcoBee (no affiliation) so I'll speak to that. The selling point to me with this was the room sensors, which have temperature and motion. I have 3 in the house, plus the main thermostat (which itself has ...


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Depends on where you would set things, the insulation, etc. You would really need to test it yourself (to the extent possible) to see what is possible. Why might it help? Your heater has one job: to replace the thermal energy inside the dwelling that has been lost. If replaced exactly, the temperature is maintained. For most structures with reasonable ...


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I only worked in the commercial/industrial field of steam and hot water boilers so take what I say lightly. Here is what the heating engineers told us; if you can set back the thermostat or reduce the buildings temperature for 8 hours or more then there is a cost savings and if you can't it is probably not worth anything. One of the main problems with ...


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It all depends how do you set up your not-smart thermostat VS how do you plan to set up your smart thermostat. They don't just save energy for the same use. If you set up non-smart thermostat for 'comfort always' you will pay more. If you will set up it as 'discomfort always' you will pay less. For the same level of comfort you need different temperature at ...


1

I'm currently running such a setup with an Aprilaire 8620W thermostat. AC from the heat pump, Heat from the heat pump when outside temp is >=40F, Emergency Heat from the boiler kicks in when outside temp is <40F. The thermostat initially installed was a Honeywell model, and that could be configured to support AC, or could be configured to support Heat,...


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This is quite definitely possible, and actually a relatively good setup What you describe (a heat pump with hydronic backup heat) is quite supportable by most thermostats that can support a two-transformer, single-stage heat pump system. Rc, C, Y, G, and O/B from the thermostat are brought to the air handler, with C, Y, and O/B continuing to the heat pump ...


1

Heat loss or heat gain is how fixed heating is installed. What that means to keep a uniform temp in the room we put registers under / over windows . Where the outside temp affects the room more. I don’t find mini splits following this quite as much possibly because there air discharge is 3-5x the area of a fixed vent and the minis usually have active vents ...


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In summer the attic is heated by the sun through the roof and windows and also by warm air rising from the rest of the house through the staircase. Closing the attic door would reduce the amount of warm air rising, but that is not the main source of heat. The sun is. And closing the door also decreases the flow of air from the attic registers back to the ...


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Two separate issues here: Attics Get Hot! This is a fact of life. Attics heat up from the sun all day long. Color and type of roof can make some difference (reflection vs. absorption), but it is quite normal for an attic to get really hot. The usual solution is an attic fan. This can be thermostatically controlled so it only runs when hot. For an attic fan ...


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Summary... 100% add the duct work. It will be cheaper in long run, look better, and will increase resale value of the home. Few things here: Once you add those walls/ceilings (given it is not a drop ceiling) adding duct work will be very costly and messy. This is sort of like running ethernet cable throughout the house, but air ducts probably have ...


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One thing you could consider would be to install dampers in the duct work to close off various legs of duct. This would allow you to have heat available anywhere in the house you want, but to close off areas from heating when you don't want them to be heated. This would, effectively, give you multiple zones, though they'd be manually controlled. Also, adding ...


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TL;DR Space heating doesn't make sense in a typical US house that already has duct work in place. There are, broadly speaking, 3 types of home heating in general use in the US: Fossil fuels - Natural gas (generally most cost effective) or oil. If you have this, it would definitely be forced air, as that matches "duct work". Electric resistance ...


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If you can shorten the hose significantly from its max length, this will compensate. Very likely a short section of 4 inch diameter through the wall could give full performance. A slightly longer, more gradual transition piece might work better than a shorter more abrupt transition. I think the 4th power dependence of flow resistance in a circular cross ...


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No! Stop! You're heading down the road to ice-dam damnation! The problem with throwing ducts in a presumably-vented attic in your climate is that when that snow comes, all the heat from the ducts is going to heat the roof up above freezing, melting the snow, which then refreezes as things cool off further, leading to the dreaded ice dam. (It's also a waste ...


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You need about 1 ton of cooling per 400 sq/ft. At 1,400 square feet you will be undersized by about 1.5 tons. If you have excellent insulation everywhere then 2 tons might work but you will likely notice that your unit is constantly working on high for hours on end. Also, from https://www.cooltoday.com/blog/is-it-bad-if-my-evaporator-coils-and-condenser-...


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The reason to pull a vacuum 0n an A/C system is not just to remove the air. The real reason to pull a vacuum on the system is to yes, remove the air, but is also to remove any moisture that will get into the system when the lines are cut and the removed compressor is exposed to the atmosphere. What you are trying to do has some merit but in no way is the ...


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Yes a refrigerator compressor can pull a vacuum but it may not last long because as you reach a vacuum there is no air to transfer the heat away from the windings. The heat buildup and motor failure this is something taught in hvac training when you pump Down a system using its own compressor. you don’t run it at a vacuum or you will smoke the compressor ...


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