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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

#331

Post by DoingIsLearning »

Tade0 wrote: post #237
darknavi wrote: post #203

Earlier quoted context omitted.

That can work just fine by intentionally opening windows. Having a "drafty" house is just forcing that 100% of the time (which isn't always wanted). Side note: As a US resident in an area with a ton of mosquitos, I cannot understand why other countries don't heavily use window screens. Lizards a pretty cool, flies and other flying bugs are just annoying and gross.

In Europe, outside of the south, mosquitoes are pretty tame. After spending some years in Italy I developed a partial immunity to mosquito bites. It lasted for about half a year.

> In Europe, outside of the south, mosquitoes are pretty tame.

Use to be... native species were mostly a problem during summer and during night time.

But since about 15 years ago you had a massive spread of invasive Asian Tiger mosquitos (Aedes albopictus) genomic studies show it was likely introduced via Italy and Albania simultaneously.

Those things are nasty, go 24/7, and are just a very different beast in terms of disease vector.

There are already established population pockets as far North as Switzerland. Yet another problem that is likely to worsen as temperatures continue to rise.

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

#332

Post by bthater »

hawaiianbrah wrote: post #307
IAmGraydon wrote: post #232

Earlier quoted context omitted.

Are you asking why the Daikin Alira X is more expensive in the US? It's because it's not a brand that is normally found here. If you went with a common US brand you can get a good system with 4 units and a 36,000 BTU heat pump unit for around $6,500 USD installed. I don't love the wall units - they're pretty ugly, even the new ones. If you're getting a mini-split, the in-ceiling or wall cassettes that are hidden are…

Wow, really? Prices seem much higher than that in Seattle. A friend got 3 handlers totaling 24k BTU for like 12 grand.

Seems to just be Seattle tax, I had to get a water line replaced in my home and the quotes were $2-7k higher than I've seen suggested in other regions. Tradework here is inflated likely by the salaries of tech workers in the city.

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

#333

Post by EricE »

I don't know where the heck all this extra electricity for heat pumps and electric car charging is going to come from. In CA if you get a slightly hotter than average summer their electrical grid goes into chaos. Get a slightly colder than normal winter and the north east and central grid freaks out. I'm all for transitioning to renewable energy (nuclear makes the most sense if you take emotion and bullshit out of it) but we have a long way to go before we can just ditch gasoline, diesel and natural gas any time soon. Heck how many millions of US homes will have to get their electrical service upgraded, never mind the base electric infrastructure?

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

#334

Post by Sytten »

nemo44x wrote: post #166
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.

It’s not always possible. For instance old wood double hung sash windows require a weight box to work. Those boxes can’t really be insulated. And there’s a good chance you don’t want to replace the old windows (or possibly can’t due to historic restrictions) because they are a massive part of the homes character. Also insulating an old home (pre-WW2) could begin to introduce moisture issues in the walls that weren’t…

On the contrary modern houses often rot because of the water barrier. Condensation gets trapped in the wall and it rots really fast. If you insulate your old house from the inside you wont have this issue. I spent the last 3 years remodelling at 1875 house and we opened all the walls to spray urethane foam. It sealed all the cracks between the wood beams but still leaves the exterior untouched to moisture can leave.

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

#335

Post by EricE »

fifteenforty wrote: post #269
darken wrote: post #266

Earlier quoted context omitted.

I love our Daikin mini-splits (came with the house), but as you allude to I've had to become an mini expert on deep cleaning them. They've can get GROSS with mold when used for cooling, and the cursory filter only does so much. That being said, now they stay clean for a few years after a deep cleaning -- though my first few attempt before I refined the process did not stay clean nearly as long. (Proper water pressure…

The no 1 reason I bought the Daikin model referenced over the comparable Mitsubishi Electric is that it has the ‘MOULD PROOF’ function. It runs the fan automatically after you have had it in cooling mode, to evaporate the moisture build up from the interior condenser coil, thereby removing the moisture required for the growth of bacteria and mould. So far, it seems to be working! Better than relying on everyone to ma…

If you live in any kind of area with high humidity you just shifted the mold from the AC unit to the rest of your house. Hell even here in the desert I'm not sure I'd want to use that "feature".

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

#336

Post by EricE »

toomuchtodo wrote: post #303
thehappypm wrote: post #296

Earlier quoted context omitted.

I live in a cold climate

Mitsubishi is gold standard in cold climates. It’ll pull heat from -30F air.

There's no reason that's unique to Misubishi. My parents Fujitsu has done so.

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

#337

Post by devwastaken »

EricE wrote: post #333

I don't know where the heck all this extra electricity for heat pumps and electric car charging is going to come from. In CA if you get a slightly hotter than average summer their electrical grid goes into chaos. Get a slightly colder than normal winter and the north east and central grid freaks out. I'm all for transitioning to renewable energy (nuclear makes the most sense if you take emotion and bullshit out of it…

A heat pump operates at 2x to 4x the power efficiency as compared to resistive heating. Many places are unfortunately only doing resistive heating because of cheap install cost. If we can replace that with a heat pump that's a big win for everyone.

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

#338

Post by EricE »

Dylan16807 wrote: post #227
fifteenforty wrote: post #215

Earlier quoted context omitted.

Approximately 70% of the heat loss from your body is as radiated heat. Ceiling insulation is critical for thermal comfort. Have a look at the Efficiency Matrix YouTube channel videos on insulation consistency.

The average temperature sure. But would uneven spots have that much effect on the thermal radiation I get sitting over a meter away?

Less that 2% of insulation being out of place can waste something like 40% or some ridiculous amount of energy. It's quite nuts how even just a little break in insulation can have a significantly negative effect. A few years after I moved into my first home - a townhouse - I added some R-16 bats to the already existing R-12 insulation in the attic and it more than cut my heating bill in half. It was a three story narrow, townhouse - not that much square footage of ceiling compared to the walls/rest of the house but it made ALL the difference. If I didn't live it, I wouldn't have believed it. And I kind of did it on a whim since I didn't need that many and Lowes was having a sale on insulation. I would have done it the first week I moved in and had a couple far more comfortable winters!

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

#339

Post by EricE »

fifteenforty wrote: post #216
Karupan wrote: post #212

Earlier quoted context omitted.

I got a similar setup for my house as well. Being able to selectively cool rooms that are in use is great. However, I do wish the insulation was far better. Unfortunately I’ve noticed that Melbourne houses are usually very poorly constructed due to expensive raw materials and labour.

Have you examined your insulation with a thermal camera? Might be worth your while to get an energy inspector out. Personally I haven’t yet, mostly because I can still see low hanging fruit to fix.

You don't even need a pro - you can get FLIR cameras that attach to cell phones for around $100 and they are more than adequate to show you areas of irregularity and worthy of targeting. I got one years ago mainly as just something to play with but I use it ALL the time for all kinds of things. Having a thermal camera is crazy useful.

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

#340

Post by EricE »

Gordonjcp wrote: post #146
fifteenforty wrote: post #112

Earlier quoted context omitted.

You have to think carefully about where you run the ducts. They can be a huge source of energy loss. 40% is the number quoted by the EPA. Most roofs in Australia still aren’t sealed. The air barrier and insulation barrier is the ceiling. The roof space itself is not insulated, so the ducts are exposed to extreme temperatures, thus destroying the efficiency. Here is just one article on it: https://newenergythinking.co…

Why wouldn't you just lay insulation on the ducts, same as you do with water pipes?

Over insulation introduces new problems like condensation (which causes mold and other nastiness)

https://www.youtube.com/watch?v=Vufih-WN5R4

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