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Heat pumps of the 1800s are becoming the technology of the future

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Re: Heat pumps of the 1800s are becoming the technology of the future

#281

Post by redeeman »

ChainOfFools wrote: post #165
nickpeterson wrote: post #4

Why can’t my whole home participate in this technology? It would seem an ok fit for things like freezers, refrigerators, hot water heaters, etc. When it’s freezing cold outside, it seems crazy that I warm the air of my house and then use electricity to keep the fridge cooler than the air I just heated. Someone needs to make a standard for moving heat/cool through all appliances in a house…

Devices are beginning to appear that can move the waste heat generated by home AC compressor into the pump loop for a swimming pool outside that same home, getting your pool heated for free by cooling your house, and your aircon cooling becoming much more efficient by using your swimming pool as a giant heat sink. However unless the house was built, and / or the pool installed in a coincidentally fortunate configurat…

> nd the pool filter pump are within a meter or two of each other, these devices cannot be used effectively due to impractical tolerances and insulation needed to mitigate losses from contact with the highly variable outdoor environment.

that makes no sense. effective insulation is no problem at all. In large parts of europe they even have centralized water heating and run insulated hotwater pipes to houses across kilometers without huge losses, hell, for this kind of setup it would even be possible to just run refridgerant, which typically specs at ~15m for minisplits as maximum(with very minor losses) distance

Re: Heat pumps of the 1800s are becoming the technology of the future

#282

Post by lll-o-lll »

goodpoint wrote: post #255
lll-o-lll wrote: post #192

Earlier quoted context omitted.

If you live in a warm climate, I personally think insulation is the worst (excepting roofing). Not because of efficiency, but because you isolate yourself from nature! The traditional Queenslander (look up Bluey if you don’t know what I mean), has so much going for it. It allows airflow through the whole house, a protected outside to sit and be with nature, lizards coming and going, bliss! This hermetically sealed en…

> you isolate yourself from nature That's a feature not a bug. > This hermetically sealed environment that we create for ourselves is bad for us. Not at all. Heat recovery vents exist for a reason!

Not physically. Bad for our souls.

Re: Heat pumps of the 1800s are becoming the technology of the future

#283

Post by PaulHoule »

fifteenforty wrote: post #109

In a house I own in Melbourne, Australia, I just replaced an old gas central heating system with 3 new top of the line Daikin mini split heat pumps. The new units can heat the entire house for the same amount of electrical energy that was used to run the FAN in the old gas unit. They are crazy efficient. Ducts are dead. The Daikin Alira X is the gold-plated option and cost $8k AUD for 2x2.5kw and 1x7.1kw units includ…

It doesn't get that cold in most places in Australia does it?

Heat pumps need to be scaled for the maximum heating or cooling load, whichever is greater. The optimal situation is that the heating and cooling loads are similar, but in colder parts of the U.S. the heating load is much larger than the cooling load and the case for the heat pump is not so good as a place where the need for heating and cooling are more balanced.

Re: Heat pumps of the 1800s are becoming the technology of the future

#284

Post by lll-o-lll »

JenrHywy wrote: post #271
lll-o-lll wrote: post #192

Earlier quoted context omitted.

If you live in a warm climate, I personally think insulation is the worst (excepting roofing). Not because of efficiency, but because you isolate yourself from nature! The traditional Queenslander (look up Bluey if you don’t know what I mean), has so much going for it. It allows airflow through the whole house, a protected outside to sit and be with nature, lizards coming and going, bliss! This hermetically sealed en…

Queenslanders work fine in Queensland, where the lows in winter are still double-digit C. Most of the world (or even Aus) isn't like that. A Queenslander in Canberra would have a massive heating bill 8 months of the year to keep it safely livable.

I said “warm climate”, Canberra does not qualify. Also, plenty of Queensland is single digit C at times in winter, even zero.

Then you put on a jumper, or use a bit of radiant heat if really soft.

Re: Heat pumps of the 1800s are becoming the technology of the future

#285

Post by lll-o-lll »

siod wrote: post #233
lll-o-lll wrote: post #192

Earlier quoted context omitted.

If you live in a warm climate, I personally think insulation is the worst (excepting roofing). Not because of efficiency, but because you isolate yourself from nature! The traditional Queenslander (look up Bluey if you don’t know what I mean), has so much going for it. It allows airflow through the whole house, a protected outside to sit and be with nature, lizards coming and going, bliss! This hermetically sealed en…

The Queenslander house style was built for large blocks that had sufficient airflow, they were built to be cheap and don't work properly with modern block sizes. While they are iconic, and have some great design features, the lack of insulation is not one of them. A modern well insulated house with a heatpump + solar is extremely energy efficient and comfortable in all weather.

“Modern block sizes” will vary where you live, and you can build smaller of course.

Obviously this is location dependent advice. If you live in a lifeless suburban wasteland, then outside is no better than inside. If, on the other hand, there is nature around you, and it doesn’t get too cold in winter, then insulation is a pointless exercise! Get a ceiling fan and learn to tolerate a bit of heat.

I, personally, need nature to stay mentally healthy, and having nature wander inside from time to time helps greatly.

Re: Heat pumps of the 1800s are becoming the technology of the future

#286

Post by jethro_tell »

throw0101a wrote: post #118
fifteenforty wrote: post #109

In a house I own in Melbourne, Australia, I just replaced an old gas central heating system with 3 new top of the line Daikin mini split heat pumps. The new units can heat the entire house for the same amount of electrical energy that was used to run the FAN in the old gas unit. They are crazy efficient. Ducts are dead. The Daikin Alira X is the gold-plated option and cost $8k AUD for 2x2.5kw and 1x7.1kw units includ…

> Ducts are dead. Ducts are still needed to circulate air, especially if you want to remove stale air (e.g., bathrooms, kitchen) and bring in (filtered) fresh air (to bedrooms).

In have ducted mini split units in my home, made by Mitsubishi I designed the system to work with merv 13-16 filters. I can run the fans and filter my air as well as use the units for heat and cooling. I installed fresh air intakes on the return units that can pull external air when they are opened.

It's really a very good proposition. Has all of the advantages of central heating and the efficiencies the heat pumps

Re: Heat pumps of the 1800s are becoming the technology of the future

#288

Post by thehappypm »

teruakohatu wrote: post #270
thehappypm wrote: post #248

Earlier quoted context omitted.

I have two units that are heated by heat pumps in Massachusetts. One has mini splits. You definitely don’t generally put mini splits in every single room (like bathrooms or interior hallways) because each mini split requires tubing, is large, and expensive. No, I think it’s way more likely that you would have them in the bedrooms rather than the hallway

In New Zealand I have seen small heatpumps in bedrooms, but I would have to say it is extremely rare. But we have many very toasty hallways leading to cold single glazed bedrooms!

That might be a climate difference — it gets below 0 Fahrenheit here every winter, as I understand it, NZ is quite a bit warmer, so maybe the strategy of “heat the core of the house and let it radiate out” works.

Re: Heat pumps of the 1800s are becoming the technology of the future

#289

Post by thadk »

jwcooper wrote: post #148
kccqzy wrote: post #132

Earlier quoted context omitted.

Not being snarky but why don't you just open the window for that? I have a CO2 detector that I believe is a reasonable proxy for stale air. When it goes above 1000 I simply open the windows. By the time I remember to close the windows the reading is almost always below 500.

Where I live, it can get very cold. Not always very efficient to open windows for 5 months out of the year. A great option for keeping CO2 levels down in a house is with an HRV (or ERV) [1] that will heat the fresh air coming in to cycle it throughout the house. [1] https://en.wikipedia.org/wiki/Heat_recovery_ventilation

There is an open source 3D printable unit design here which I installed in my window and works well for relatively efficiently exhausting the CO2 from one person in cold weather: https://www.openerv.org (license: CC BY-NC-SA 3.0)

I did not 3D print mine, but ordered it, though as an early adopter, adjustment was required.

Re: Heat pumps of the 1800s are becoming the technology of the future

#290

Post by yaysyu »

PaulHoule wrote: post #283
fifteenforty wrote: post #109

In a house I own in Melbourne, Australia, I just replaced an old gas central heating system with 3 new top of the line Daikin mini split heat pumps. The new units can heat the entire house for the same amount of electrical energy that was used to run the FAN in the old gas unit. They are crazy efficient. Ducts are dead. The Daikin Alira X is the gold-plated option and cost $8k AUD for 2x2.5kw and 1x7.1kw units includ…

It doesn't get that cold in most places in Australia does it? Heat pumps need to be scaled for the maximum heating or cooling load, whichever is greater. The optimal situation is that the heating and cooling loads are similar, but in colder parts of the U.S. the heating load is much larger than the cooling load and the case for the heat pump is not so good as a place where the need for heating and cooling are more ba…

Depends on your frame of reference but in Melbourne it can get to around 1 degree Celcius in winter (33~F). Sometimes subzero but very rarely
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