I had a TOSOT mini split installed this summer, and so far I've just been cleaning the filters every now and then. Now that winter is coming up, I'm wondering if there's anything else I should be doing to get it ready for heating season.

Do you guys clean the blower wheel and coil yourselves, or is that something you leave to an HVAC tech? Is it even necessary to do a deeper cleaning after just one summer of use?

We just bought a house and I don't seem to find any documentation on the ACs. I have 2 Mitsubishi AC units that are connected to the same outer unit (or whatever it's called). I know that they have to be set up to the same setting, so that they don't collide.

One of the ACs seems to be slacking and there is this "off" (above the temp) sign. What does that sign mean? The unit doesn't really keep the temperature up properly, but it does start working here and there

Looking at new house, it has this heatpump for heat/ac, and wondering how it will do to keep the house at 70 deg when we have 0 deg F nights in Jan. This pump covers 2.5k sq ft. I have never heard of this brand, no idea how well it will do, how long it will last, maintenance, etc. Any comments from experienced people is greatly appreciated.

Installed 3 years ago.

House is very old and mold is an issue I've had to deal with before, and probably have to again and again

I am investigating whether to partially migrate my house to A2A heat pumps. The idea at first is to install one on the ground floor, and one on the 2nd floor main bedroom. Middle floor would be left open for possible later implementation, and the gas heating system would stay in place.

The objective is to start the process or reducing gas usage and moving to heat pumps, starting with the most used areas of the house, and secondly the benefit of having AC in the summer is a bonus.

The first proposal I've received is for 1 x 3.5KW ducted unit in the top floor room, and a 5KW unit in the lounge (Fujitsu equipment) which will cover the lounge, kitchen and to some extent the dining room. It might be that we would need to add a second smaller unit on the ground floor at a later date if wanting to decommission gas totally. 8KW multi split unit to be installed outside, raised to higher than ground level in order to leave room for potential additional batteries on the Solar/battery install (alrady in place).

The rough idea is to use off peak power stored in batteries (or solar power) to heat/cool the house as much as possible. We have 19KWH of batteries and 7KW solar system installed, with possiblitity to increase to max 38KWH of batteries (I don't have a quote for additional batteries yet). At the moment we tend to export on most days except in deep winter as we don't need the capacity just to cover house load except when there is almost zero solar.

The all in price they quoted is £7K (including a scafollding allowance TBC).

I asked them to quote with keeping in mind that we might want to get rid of gas at some point in the next 10 years so more units might have to be added.

This is the same company that installed my solar/battery and they did a good job.

Does this roughly make sense, and if I use this units as the primary source of heat/cooling at the ground floor and top floor areas (only backed up by gas if extremely cold), what kind of daily usage in KWh should I expect? I'm assuming/hoping it doesn't use 8.5KW continuously.

hi friends. Last March we got two mitsubishi mini-splits in our 2-story, 1800 sq ft house in New England. I mostly got them for AC but they just work so damn well heating the house. I’d like advice for best practices this winter. our basement is unfinished but decently insulated. with waste heat from the oil furnace, it typically stays around 59F even with the heat pump hot water heater down there. from mid-March onward, I barely ran the furnace and the lowest the basement got to was 48F during 20F nights.

At this point I’m not interested in adding a zone or anything to the basement, but what would work best with my set up in the dead of winter to avoid freezing pipes in the basement and keep it somewhat habitable for laundry, working out, etc? I hope this makes sense. thanks for your time!

Installed Samsung mini split heat pumps a few months ago in northern Maine. Starting to get in the cold months and just started using them to heat. I have an emporia energy monitor hooked up and it appears the compressor is short cycling. 35k outdoor compressor with 24k head in living room(also includes dining, kitchen area as is an open floor plan) and 9k in a bedroom on the same level.. Currently we only have the living room head on. It seems the compressor turns on runs for 6 minutes, shuts off for 6 mins and then turns back on repeating throughout the whole day. I've attached pictures of the energy graph. From my phone research, shouldn't the compressor only power on and off 2-3 times per hour. Mine is currently turning on and off 6 times per hour. Am I correct to assume this is short cycling which is bad for the compressor and uses more energy?

I purchased a cielo breez max to try to stop the short cycling but that I think only works if I use it with the comfy/comfy max mode. With comfy mode, I can set it so it runs until it hits 2 degrees above set point and then turns the unit off until it's one degree below setpoint. Comfy max would use an algorithm to adjust the settings to keep it at the desired temperature but I think that could cause problems considering it's a multi head unit. I'm not sure if the thermostat shutting the mini split off a few times a day is better or worse than it short cycling. Ideally I'd let to just set it and forget it at a certain temperature and not have it short cycling but if I just set it on the cielo thermostat it continues to use the Samsung internal thermostat.

Any help is appreciated! Trying to find the most energy efficient way to use this before the real cold weather gets here.

I thought replacing my oil boiler would be a simple get three quotes, pick the reasonable one, move on situation, but apparently not. One contractor said cold weather heat pumps are basically magic now, another acted like I was asking to heat the house with candles, and the third guy seemed pretty normal but recommended a midea I hadn’t really considered. my first thought was, “is this just the cheaper option he makes better margins on?” but then he walked me through the sizing, the low-temp capacity, and why an inverter heat pump matters more than the logo on the cabinet. now i’m stuck in that annoying middle ground where the lower quote might actually make sense, but I also don’t want to save money and end up needing space heaters in february. For people in a genuinely cold climate, what do you trust more the brand name, the installer’s math, or actual homeowner feedback? every contractor review I can find from 2026 sounds either oddly sponsored or really angry, and I just want one boring, honest answer.

I live in south Georgia, where it is very hot and humid. We only get a handful of really cold days a year (really cold is in the teens and 20s lol). I've been reading up on ac units because ours is going out and is currently a single stage. I've read that 2 stage and those inverter or variable type units are more efficient and are better at reducing humidity, and I kind of hate how ours is either off or on full blast. The first company I called installs Daikin, but they pretty much only install the single stage models and actually are trying to talk me out of the other models which I thought was odd but 🤷‍♀️.

The other reputable company in town uses Carrier, and I'm currently waiting on a call back to talk to them about a quote as well.

My house is ~1800 sqft. Any advice is appreciated.

Central PA, two story colonial, 2200 sq ft. Gas furnace is 16 and probably doesnt have much runway left. I get the efficiency argument for heat pumps in moderate climates but PA winters regularly hit teens and sometimes single digits. Am I just gonna be running aux strips half the winter paying more than gas?

Want to hear from people in similar climates who have actually lived through at least one full winter. Not the theory, the reality.

Necesito un consejo, o saber si esto le ha pasado a alguien más.

​Instalé una unidad nueva de bomba de calor GE. Después de instalarla, el lado de baja estaba marcando 90 PSI. Agregué refrigerante R454B, y no pasaba de 125 PSI en el lado de baja y 300 PSI en el lado de alta. La temperatura del lado de baja es de 68°F y la del lado de alta es de 75°F. La configuración del termostato está correcta. Cuando enciendo el modo de Enfriamiento, no enfría, y cuando enciendo el modo de Calor, sigue funcionando en modo Enfriamiento. Configuré el termostato en 'O' y en 'B', y sigue haciendo lo mismo. Por favor, ayúdenme.

Hi guys

I know usually the Flexx 36’s are paired with 2 or 3 ton coils, but I also know with the dip switches on the outdoor unit you can enable energy saving mode which makes the unit act 0.5 ton smaller so you can get 2.5T. In that situation is a 2.5T evap coil okay to use or does the unit still need a 3 ton evap? I have a 2.5T evap already installed which is why I’m asking

We have a new heat pump Daikin Altherma ETBH12EF9W and I am quite disappointed by it's efficiency. Now, it is just October, so the temperatures are still very mild and we do not need too much heating power. In this regime, I found out that it actually seems that the machine gets more efficient when the temperature of the heating water is set to a higher value (like 35 C) than having it on the minimum of 27. Once I ran it for about 11 hours on 28 C and it estimated the energy consumption of 4 kWh and heat production 9 kWh. Another day I tried to run it for 5 hour on 35 C and it estimated the consumption of 2kWh and heat production 9 kWh. We have 22 C inside, so the product of temperature difference and time in both cases is about the same, so the heat production should indeed be the same, so the machine's estimate is not wrong (or it is equally wrong for both cases). This was during the day. Last night, I let it run for 27 C and now it absurdly reports higher energy consuption that heat production, which I find really unacceptable. I thought that maybe the estimate of energy consumption might be off, but checking against the power meter of our house suggests it really consumes the energy on this scale.
I guess the solution is to run on a higher temperature for a shorter time then. But it is disappointing anyway. I was looking forward to having a stable temperature for the whole day. We even do not have the thermostat because I was told it is not necessery and it would indeed not be necessary if the heat pump could run continuously. But this way it is just wasting energy. Do you have a similar experience?

I live in CT and have a 25 year old oil furnace and 23 year old AC central air unit in a 2200 sq ft colonial. CT offers rebates up to 6-7k in my case. I had an energy audit and I think I need to use the rebates this year or wait another 6 years to become eligible for another energy audit to qualify for the rebate again.

My heater and AC seem to be working fine but given their age im considering replacing with a heat pump or heat pump plus 2 mini splits.

How likely is it that my current setup lasts 6 more years? What are the reasons to wait for system failure before upgrading?

We're looking to replace the 15 year old forced-air natural gas furnace and central A/C system in our 1100sq foot 1960's elevated bungalow in Eastern Ontario with a new natural gas furnace and heat pump. If heating was the only consideration, I'd probably skip including the heat pump, but as our existing A/C is approaching end-of-life, I've asked for proposals to replace both.

A sales person from one company proposed a 70000btu furnace and a non-cold-climate heat pump. The size of the furnace surprised me, as our current furnace is 60000btu and has always been adequate. And the recommendation for non-cold-climate heat pump left me scratching my head.

Am I missing something?

[Please read to the end before commenting, especially the part where the single head continuously emits heat until the set temp is reached). ]

I’m trying to establish whether my system’s behavior is normal thermostat cycling or harmful short cycling, particularly when only one small indoor head is running.

My setup is Midea Extreme Heat:

• Outdoor: 1 × MO6HX-H60B-2A, 5-ton multi-zone.
• Indoor: 1 × MSEHU-H24B-2A, 24,000 BTU.
• Indoor: 1 × MSEHU-H12B-2A, 12,000 BTU.
• Indoor: 3 × MSEHU-H06B-2A, 6,000 BTU each.

The house is approximately 2,600 sq. ft. over two floors in northwest British Columbia. Outdoor temperatures are currently around 8°C during the day and 1–3°C at night.

Upstairs has the 24k head in the open living/dining/kitchen area and a 6k head in the bedroom. Downstairs has the 12k head in the open area and two 6k bedroom/office heads.

I normally use four or five heads in HEAT mode with AUTO fan, without extra features enabled. With four or five heads on, operation is normal: the heat pump runs continuously for hours, with my subpanel meter showing approximately 1,200–1,400 W. The cycling I’m asking about occurs when I run only one 6k head, as follows:

1. When I turn it on, the outdoor unit ramps up and the indoor head starts delivering warm air.
2. As long as the head has not reached its set temperature, heating continues without interruption. I have confirmed this. Actual compressor frequency has shown around 20 Hz while heating.
3. Once the head senses that the set temperature has been reached, power drops sharply and the compressor appears to stop.
4. The indoor fan continues running slowly. The airflow feels cooler than during heating, but it isn’t cold.
5. After approximately 15 minutes, the outdoor unit starts heating again. Warm airflow continues for several minutes until the head reaches its setpoint, and the sequence repeats. Earlier measurements showed heating runs of roughly 7–10 minutes, with pauses sometimes around 20 minutes.

Power-measurement clarification: My monitor measures a shared subpanel with approximately 160 W of unrelated loads. In the one-head test, it reads around 1,200 W during heating and 200–210 W during pauses. After subtracting that baseline, the heat pump itself uses roughly 1,040 W while heating and 40–50 W during pauses.

The room-temperature swings and the head’s sensor apparently staying warm longer than the occupied part of the room are another issue I’ll investigate separately. My main question here is:

Does this constitute short cycling, and is it likely to harm the compressor—even though it runs continuously while heat is requested and stops only when the head senses its setpoint?

For this particular outdoor model, what run-time, off-time or starts-per-hour criteria would distinguish expected low-load cycling from a problem that needs correction? Manufacturer documentation or experience with this Midea platform would be especially helpful.

I am not interested in a textbook answer "using a single head is not what this system was designed for", I get it, and understand that. I am asking specifically whether the observed heavior with only one head on constitutes short-cycling and is harmful to the compressor over time?

OilPrice: "Heat Pumps Are Coming for Coal’s Industrial Heat Market," by Haley Zaremba.

'A challenging target is coal-fired heat in hard-to-abate sectors, a tougher job than the low-temperature building heat pumps that get most of the attention." A new breakthrough in high-temperature heat pumps could provide a critical pathway toward relieving global reliance on fossil fuels in industrial contexts. "A team of scientists at the [famed] Fraunhofer Institute for Solar Energy Systems ISE (Fraunhofer ISE) in Germany tested heat pumps at 320ºF = 160ºC and proved that they can produce hot water + steam, showing promise for replacing coal in hard-to-abate manufacturing sectors."

“Data collected from the test rig could allow manufacturers to design heat pumps + heat exchangers for high temperatures, large loads, + changing conditions,” states a recent report. According to the International Energy Agency’s definition of a heat pump, the technology can extract heat from sources including “the surrounding air, geothermal energy underground, or nearby sources of water or waste heat from a factory.” The configuration of a heat pump includes a compressor, which propels a refrigerant through a closed loop, and a heat exchanger, which extracts thermal energy from a given heat source, in this case butane used not as a fuel but rather a refrigerant or "phase change material."

Globally, the energy for industrial applications largely comes from coal, the world’s dirtiest fossil fuel. "The data being produced at Fraunhofer ISE could help refine a new generation of safe, cost-effective, and low-emissions industrial processes at a time when decarbonization is sorely needed." Targeting hard-to-abate manufacturing processes is one of the trickiest parts of the decarbonization puzzle, and one that we’re now one step closer to solving. 

This is one of the many puzzle pieces we need—eliminating coal burners to rapidly combat global warming.

so I am in the middle of planning a major heat pump retrofit across a 6-unit multifamily building because the old heating system is practically ancient but every single contractor I bring out is giving me completely different structural advice on where to put the air handlers... one guy wants to frame out new utility closets right in the middle of the living areas which steals valuable square footage and will absolutely make the units harder to rent but another guy is heavily pushing for a ceiling-mounted pancake AHU tucked above the hallway ceilings

tbh the ceiling option sounds way cleaner on paper because it preserves floor space but I am secretly terrified of future condensate leaks completely ruining the drywall or some tech charging me double for maintenance because it is a pain to get to... some local investors told me these low-profile units are a ticking time bomb for tenant rentals while others swear it is the only way to save space in tight floor plans...

what are you guys actually running in your older buildings right now because I need to sign off on a quote soon and I do not want to screw myself long-term lol

Does anyone know of a discount code or anything for HeatGeek?

Apologies if not allowed but I'm mid renovation and so trying to save where possible, I was going to get a cheaper install through BG or Octopus but I've been sold on the idea of HeatGeek and so at least want to get a survey from them. I know they did a discount in August but can't find any current codes. No worries if there's nothing out there but just thought I would ask.

Is this factory?

I get this noise heard in the video from near the heat pump boiler. My unit is a Samsung air to water heat pump. Any ideas what this could be?

I have an aging gas boiler with in floor circulating water for heat in Cape Cod MA. Wondering if it makes sense to replace it with an air to water heat pump. I would be curious if anyone has done it and what their experience has been.

Hi guys

Has anyone installed a cyclinder with built in heat pump?

I'm looking at the Mixergy IHP X, the Dimplex Edel, Ariston Nuos etc?

Any advice would be greatly appreciated 👏 Does it work well, decent heat up times, noise?!?

Thanks

James

been working in this space for a while matching property owners to incentives and contractors, and this question keeps coming up now that the new $2,000-$10,000 federal rebate is out there, so i actually dug into it properly instead of just assuming.

short answer: canadian heat pump manufacturing is thin, but its not literally zero like alot of ppl assume. a few real ones:

• maritime geothermal (petitcodiac, NB) actually makes their Nordic brand geothermal AND air source heat pumps in house, real 30,000 sqft plant, their own CSA test lab, they just got $1.64M to expand
• dettson industries (sherbrooke, QC) is canadian owned and launching their own cold climate heat pump line called Atmos
• ecologix heating technologies (cambridge, ON) makes cold climate heat pumps and actually got NRCan funding back in 2011 that led to real field deployment, not just a prototype that went nowhere

but heres the thing that surprised me, moovair, which was literally the #1 shipped heat pump brand in canada in 2024, is actually engineered and made by Midea in asia, a canadian company (master group, quebec) just distributes and adapts it for our market. its “designed for canada” not “made in canada” and i dont think most ppl buying it realize that distinction.

also worth clearing up, theres a thing called the “cold climate heat pump technology challenge” that ppl sometimes assume is a canadian program becuase it sounds so on brand for us, its actually a US DOE program (bosch, carrier, daikin, lennox, midea compete in it), not canadian at all.

and heres the part that actually matters for this post: the new $2B federal rebate has no domestic content requirement whatsoever. unlike the EV rebates which had some domestic assembly considerations baked in, this one just runs off an eligible products list with 100,000+ SKUs, doesnt matter where its made. carney himself apparently said the rebate “creates the possibility of manufacturing them here” but thats aspirational talk, not an actual requirement in the program, big difference.

so how do we actually work around that to support canadian manufacturing if we want to? honestly right now its on individual property owners, if you specifically want to support domestic manufacturing you gotta seek out brands like nordic/maritime geothermal, dettson, or ecologix yourself, the rebate wont nudge you there automaticaly like it might with a “bonus for domestic content” structure (which doesnt exist yet but could be a real policy ask down the line, similar to how it eventually got built into EV incentives). until that kind of structure exists tho, “supporting canadian manufacturing” and “getting the rebate” are two completely seperate decisions you have to make on purpose, the program doesnt connect them for you

side note, this is exactly the kind of stuff we try to surface for ppl at Solenery, solenery.com, when we match you to contractors and quotes we can flag which options are actually canadian made vs just canadian distributed if that matters to you, its a free tool...

ngl this turned into a bigger rabbit hole then i expected when i started looking into it lol, wasnt planning on writing this much but the moovair thing kinda got me

anyone here actually went with one of the canadian made options (nordic, dettson, ecologix) over the bigger imported brands? hows it been for you. and do you think the rebate should have a domestic content bonus built in, or would that just make installs more expensive/complicated for no real reason? mixed feeeliings