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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

#381

Post by turtlebits »

hawaiianbrah wrote: post #358
buildsjets wrote: post #357

Earlier quoted context omitted.

I got quoted 16 grand for the same 24k/3 zone system in the Seattle area by the guys who install thru COSTCO. I ordered the hardware myself for $4300, bought about $300 worth of tools, and installed it in one long weekend. It’s really not that difficult. Basic electric installation, some special technique and tools needed for the plumbing (University of Youtube can help), pressure test, pull vacuum, open the valves a…

I’ve been eyeing https://mrcooldiy.com/ , even easier.

The problem with Mr. Cool is that their DIY claim is because you don't cut the lineset (I believe they give you 25 ft). Any excess length you're supposed to coil up and hide, which is not ideal- plus you'll lose efficiency.

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

#382

Post by jonplackett »

Danieru wrote: post #354
jonplackett wrote: post #312

> Lord Kelvin proposed using heat pump systems for space heating way back in 1852. The first heat pump was designed and built a few years later That’s the kind of speed we need if this is going to be any help before everything’s on fire anyway. From what I can tell (in / for the UK at least) heat pumps currently aren’t that great - my dad’s boiler just died and every plumber he spoke to said heat pumps kinda suck and…

"I talked to a bunch of horse tamers and they say cars are just no good. So I bought another horse. I don't see all the hype" Similar issue in the states. HVAC specialist trash talking mini splits because a mini split's advantage of cheaper maintenance and install is meaningless to the HVAC specialist. Instead they only see the trade offs. Then they quote a bill as if installing a mini split requires a diploma and po…

This isn’t an appropriate analogy - the plumbers also fit the heat pumps. They just don’t recommend them

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

#383

Post by fifteenforty »

malandrew wrote: post #380
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…

The problem I have with mini splits is that they are an architectural eyesore. Are there any high quality ones designed to be built into walls discretely like cove lighting has done for lighting?

There are floor mounted units that can be recessed into a wall. Alternatively, ceiling cassettes (not ducts) can be good. https://www.mitsubishielectric.com.au/wp-content/uploads/202...

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

#384

Post by fifteenforty »

EricE wrote: post #339
fifteenforty wrote: post #216

Earlier quoted context omitted.

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.

I have a cheap Uni-T thermal camera. It’s great fun!

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

#385

Post by ricardo81 »

nostrademons wrote: post #174
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.

I've heard folks who work in the home energy audit business say that upgrading insulation is usually the most cost-effective thing you can do to lower energy bills. Even better, it's multiplicative with other activities like installing heat pumps or solar, so you can install a much lower capacity system and still hit your energy targets.

Most definitely. Here in Scotland, 'Home Energy Scotland' offer grants and interest free loans for various energy efficiency and renewable measures, but for the former you must install roof or cavity wall insulation if its recommended on your energy performance certificate for the building - I'd assume purely because it's the most cost effective measures when applicable.

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

#386

Post by bckygldstn »

darknavi wrote: post #203
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…

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.

As an immigrant to the US I hate the window screens and have removed the ones I can: it feels like being in prison not being able to truly open the windows. We live in an area without mosquitoes or bugs to speak of, but all the apartments here seem to have the screens anyway.

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

#387

Post by hawaiianbrah »

turtlebits wrote: post #381
hawaiianbrah wrote: post #358

Earlier quoted context omitted.

I’ve been eyeing https://mrcooldiy.com/ , even easier.

The problem with Mr. Cool is that their DIY claim is because you don't cut the lineset (I believe they give you 25 ft). Any excess length you're supposed to coil up and hide, which is not ideal- plus you'll lose efficiency.

Or you mount the condenser further is all.

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

#388

Post by stephen_g »

AlanSE wrote: post #22
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…

The fridge isn't the biggest energy hog in the house, but I'm very sympathetic to the absurdity of heat levels in a house. I often see my HVAC cooling when the set-point temperature is actually _higher_ than the outside temperature. Logically, the house is a heat generator, it makes sense physically. The roof is black, etc. It would offer a good number of benefits if the system could outright open a duct to the outdo…

The function to just bring outside air when it makes sense is an extremely common feature in commercial HVAC systems - it’s called ‘night purge’.

Most of these systems have a damper that the system can use to choose how much fresh air is used or how much return air is recirculated so it’s not difficult to use that to just put fresh air in directly with no cooling or heating. Even systems with heat or energy recovery will often have a bypass damper.

You need the humidity to be in the right range as well as the temperature, but it can save a lot of energy!

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

#389

Post by fjfaase »

I have wondered whether using a small windmill (on the roof) to power the compressor directly could work. This to prevent the energy loss of converting mechanical energy to electrical and electrical to mechanical again. Combining this with a heat/cold storage which is filled there is a lot of wind to be used when there is less, seems to be good idea as well.

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

#390

Post by imp0cat »

biofunsf wrote: post #371
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.

digression: Any recommendations for a good CO2 detector?

TFA Dostmann AirCO2ntrol Mini is a relatively cheap one that works well.
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