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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

#191

Post by thomasjb »

Scoundreller wrote: post #99
jakedata wrote: post #19

In 2017 we installed a very efficient air-source heat pump and solar panels. My electrical utility offers 1:1 buyback of electricity so I am able to build up a credit in the summer and run the heat pump well into the fall and winter on that surplus. The system is sized for cooling the house which means that it is undersized for heating, but during cool fall and spring temperatures it operates satisfactorily as a heat…

Since your natgas consumption is low, could a wood pellet heater meet your needs instead of natgas? I guess it depends if your natgas bill has a big fixed cost (and I guess you’ve already covered the sunk cost of connection…)

A wood pellet heater can be a fairly complex item, for a backup (depending on what usage frequency backup entails) a wood fired furnace might be more suitable if the owner is happy with having to add fuel every once in a while.

Myself, I would like a ground source system that lets me store in heat from an oil fired AGA, a wood burning furnace and water heater panels on the roof.

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

#192

Post by lll-o-lll »

phyzome wrote: post #144

> owners of drafty homes may need to take on the added cost of insulation when installing a heat pump Installing good insulation is also really important even if you're not using heat pumps! With bad insulation, you're wasting energy no matter what technology you're using.

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 environment that we create for ourselves is bad for us.

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

#193

Post by adrianmonk »

kccqzy wrote: post #132
throw0101a wrote: post #118

Earlier quoted context omitted.

> 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).

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.

Allergies, humidity, heat, cold, rain, noise, privacy, and the hassle of doing it manually.

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

#194

Post by EZ-Cheeze »

"Stuck at home during the first UK lockdown of the Covid-19 pandemic, the thermal engineer suddenly had all the time he needed to refine the efficiency of heat pumps"

I've seen that story a few times now. The free time let a lot of innovation happen. Fuck jobs

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

#195

Post by Symbiote »

tomohawk wrote: post #124
macinjosh wrote: post #30

Earlier quoted context omitted.

Still waiting for one of these people who rave about their heat pump system to actually rely on it full time without a backup. Most folks could barely afford to replace an existing furnace in a place that has all the fixtures installed, much less pay to install a second one based on different setup, and then pay for maintaining two systems on top of everything else. It is absurd to think that this is a plausible way…

The article is light on technical details, pointing to a heat pump vendor site for "proof" that they're great. I live in a heavily populated area with high standard of living, and yet we have had power outages lasting up to a week in the years we've lived here. Almost all in the winter, but also some due to hurricanes. We have have solar, which is great in the summer heat, but not as wonderful in the winter. We have…

Your normal experience is far outside what most people in Europe would prepare for, so our comments on this thread should probably be ignored by North Americans.

Looking at [1], I can see only two power cuts lasting more than 24 hours (Barcelona, 2007 and Cyprus, 2011).

Instead, "major power cut" refers to things like "The power cut occurred at 4:20 pm and power was slowly restored between 5:20 and 6:30 pm." (Glasgow, 2009.)

I can't remember being without power for more than 6 hours, and it's probably more like 3 or 4. I've been responsible for some colocated servers for about 8 years, and there's been one occasion where grid power was lost. That was about 20 minutes. A Raspberry Pi I have in a village in England has lost power once in the last three years.

[1] https://en.wikipedia.org/wiki/List_of_major_power_outages

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

#196

Post by xattt »

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…

Since this is the top comment right now, what is integration with Home Assistant/Hubitat like?

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

#197

Post by AndrewDavis »

Someone1234 wrote: post #177
jimmaswell wrote: post #151

Earlier quoted context omitted.

> Ducts are dead. How do you move the heated/cooled air into/around the house without ducts?

Just to add to what the other commentator said, ducted based systems are VERY hard to balance. It is possible using something called an Volume Damper, but it is uncommon (and adjusting them can be challenging, sometimes requiring removal of drywall). So people COMMONLY wind up with unbalanced floors, and people typically try to fix it by adjusting the vent register opening with mixed success. Part of the problem is t…

I moved from a ducted heating house to a multi head split system house about 18 months ago.

One of the biggest pros (in addition to the improved efficiency of a heat pump) is I heat and cool less space than i did before because i can target individual rooms. When i'm in my office all day I only need to heat my office. When it's hot and I'm struggling to sleep only cool my bedroom. There's no point in heating my living room^^ at 08:30 in the morning if i don't intend to spend time in there till 17:00.

Sure, when it gets to 17:00 my living area might not be comfortable, but that can easily be overcome by turning it on half an hour or so beforehand (either manually or with a timer).

^^ I don't live somewhere where freezing pipes are a concern. But i'd imagine you could just set them differently, slightly above freezing for the rooms you aren't in and a comfortable living temperature in the room you're in.

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

#198

Post by metadat »

fifteenforty wrote: post #161
newmac wrote: post #134

Earlier quoted context omitted.

Agree, ducts are wonderful! If you don't have ducts, go ductless for sure.

I paid real money to have my ducts removed. They cause issues installing comprehensive insulation and caused hot/cold spots on the ceiling.

Honest question: Why would one care about cold or hot spots on the ceiling? I don't spend much time up there.

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

#199

Post by Brybry »

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…

I don't think the hardware is that expensive in the US, it's the installation (which costs more than the hardware).

And mistakes by installers will cost even more. Our installers didn't flare a line set connection properly and it leaked slowly and that was a very expensive bill (especially since refrigerants have changed so much).

Our Daikin indoor units have also had condensate leaking issues, probably due to poor installation.

Ductless heat pumps do seem like the future but I think there are issues with regards to condensate draining, air filtering, and indoor unit cleaning/maintenance and replacement that could be done much better.

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

#200

Post by vanviegen »

ghettoCoder wrote: post #16
retrac wrote: post #10

Earlier quoted context omitted.

> 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 The fridge is simply moving a little of the warmth in your room out of its box, and adding a little more warmth to the room in the process. You lose no heat from the room, which is what matters, really. It would be worse to dump the heat outside! At least in winter. The heat has to be removed…

I always joke that in winter all appliances are 100% efficient (I know they're not). Some look at me funny but the ones who pay the gas bill get usually get it.

I think 100% is pretty accurate for most devices, except for washing machines and other gadgets connected to the sewer. Where else would the energy go?

Your fridge has the potential to go even higher than 100%, as it's a heat pump. But for more than a temporary effect you'd have to keep replacing the stuff inside it with stuff warmed up to outside temperate, which would have to be between fridge temperature and room temperature. Perhaps slightly impractical.

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