Still need to finish wrapping the lines and tidy up the cables a bit, though.
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Heat pumps are the best. Nice work
I’ve considered doing this. How difficult is it for someone with no background in HVAC?
Everything is pre-charged. It’s easy if you’re not an idiot. Hardest part is routing the lines through the house from where you want the head unit. Also, electrical if you aren’t familiar with that. Site your outdoor unit to make that as easy as possible.
Everything is pre-charged.
Not on this one, lol!
But charging it is actually not that difficult or complicated, and I was able to borrow the necessary tools (vacuum pump and refrigerant gauge set) from a brother in law. All you have to do is use a vacuum pump to suck all the air out of the lines. Then wait to ensure it holds a vacuum, so you can be sure there’s no leaks. Then disconnect the vacuum pump and turn the valves to open the system up, letting the refrigerant into the lines and the inside unit.
That’s pre-charged bud. Otherwise there wouldn’t be refrigerant included
Oh, I thought there were ones with pre-charged lines and everything, where you could just hook it up and go.
There are, and that’s the way the average joe is supposed to do one of these. Technically speaking you can’t even hook up a refrigerant manifold to a system legally without an EPA 608 cert (assuming you’re in the US). Of course the EPA doesn’t exactly have the funding or support to enforce anything right now. Even if they did, they have far bigger fish to fry than a homeowner doing their own HVAC work.
Of course, if you do want to work with refrigerants more then an EPA 608 cert is prettyeasy to get. It’s a lifetime cert and I was able to get it with a week of self study and an online test. 608 type 2 is what you need for most HVAC but really it’s not that much harder to just get the universal cert.
Some come with lines that are vacuumed or something out of the box. Aren’t most compressors pre charged?
Most refrigeration components just come with a slight nitrogen charge to keep them dry. If you’re buying a whole condensing unit it’ll often come with a refrigerant charge in the condensing unit. With heatpumps in particular though you can buy lines and components precharged with refrigerant so you can install them without an EPA certification.
Those ones are nicer for getting the lineset the actual length you want instead of having to coil up the excess somewhere, if you have or can get hold of the equipment.
Price of vac pumps and gauges is much better than when I bought them to deal with our farm equipment. If your choice was to pay someone or buy the stuff to do it yourself, it’s no question it’s cheaper to do it yourself. Every job I do on a tractor would pay for the tools all over again, every job was $1000 before that.
Where are you buying a 2 stage vac pump for cheaper than having someone else do it? Cheapest I can find a proper vac pump is like $650 and that’s because it’s a cheap model, the guys at the supply house like me, and they haven’t been able to actually move any of that particular stock in 2 years. Add a micron gauge plus manifold and you’re easily in $1000 on tools.
If I was professionally doing a vac and charge on equipment someone already had installed it’d probably cost them like $400-$500 depending on drive time. Thats also assuming the system was leak free and the customer understood that my company wouldn’t give any warranty on equipment we didn’t install. But that’s also commercial refer mechanic pricing so a residential HVAC tech should be even cheaper.
Also I agree on the linesets. I hate seeing the coils of spare lineset. But if I didn’t already have all the tools required to run custom linesets then I’d probably just buy the precharged lines and deal with it vs spending +$1000 on the tools or having them professionally run.
I have no background in HVAC, and I did it.
This youtube video was a great resource.
Hardest (or at least the most nerve-wracking) part of it was unrolling and placing the long, fragile copper tubes. They have to be handled very carefully because if they bend too sharply or too much, they can kink or crack, and then you need a whole new set of lines.
Nice. I did this last year and posted it here, too!
You should be using liquid-tite conduit for exterior wiring and to keep the kids from hanging from it.
You should be using liquid-tite conduit for exterior wiring
Heh… The exterior wiring is probably the sketchiest part of all of this. Because I cheaped out bigtime. Some time ago, my girlfriend happened to find a heavy duty extension cord that had fallen off a truck and been run over a few times. The insulation was damaged in some places, but it was a very big and heavy cord, worth saving. I spliced the longest undamaged parts of it together into a nice working extension cord that’s a bit shorter now. But I was also able to save another piece of around 12ft that hadn’t been damaged, but wasn’t worth making another joint in the cord to incorporate it. Kept that around … and now I’ve finally put (most of) that extra section to use, connecting my heat pump to wall power.
Don’t worry – it’s 12ga wire, the same as what’s feeding the thing inside the wall, and should theoretically be good up to 25 amps, while this heat pump should only pull 17 amps. But since it’s not Romex, it doesn’t have paper parts to its insulation and won’t be as sensitive to moisture. It’s also already sheathed in a thick, weather-resistant outer lining. I will be wrapping it in weather-resistant tape for additional long-term protection, though, and I’ll keep an eye on it from time to time to make sure it’s not degrading. No big deal to replace it if I need to sometime in the future, but at least for now, it should be fine, and I’m willing to see how long it lasts.
But, hey, can’t turn down free wiring, right?
and to keep the kids from hanging from it
No kids, thankfully, and none planned. Good thing too, because they’d probably want to climb all over this.
“More pumping, more now”
I wish I would be able to do it myself. But in Sweden you have to hire someone to do it. Costs about as much as a low to mid range pump.
Even with the prefilled quick connect ones?
Haven’t seen those around here. How do you solve the vacuum with those? Only monoblocks is available to the consumer.
https://mrcooldiydirect.com/collections/diy-pre-charged-hvac-systems
They come pre charged, iirc the qd uses a gas vial to purge the connector as the connection is made.
But it is worth it. Swedish houses were designed with winter in mind. In the summer, that philosophy doesn’t really help, now does it? Besides, the summers seem to get hotter every year, so that investment will make your summers more comfortable.
Yeah, have a split with two indoor unit already and its been great. Cost about 5000€ total with install But I need another for the upper floor. Since its high up the installers wanted another 500€ on top of the usual rate. That one I would love to install myself
Cost about 5000€ total with install
That’s insane. I’m at ~$700 for this one, all in. And that’s for a mid-range unit with good efficiency and able to work in cold weather (down to -13F). If I’d gotten one of the cheapest units, I could have done it all for under $400.
Costs about as much as a low to mid range pump.
At least the costs are more reasonable… Around these parts, DIY is the only reasonable way to do it, because installation could easily cost 5-10x the price of a low to mid range pump. For some reason, HVAC technicians in the US have decided that mini-splits are strange, alien technology that requires 10x more expertise (and 10x more money) to install or work on than regular air conditioners … even though they basically are regular air conditioners. They’ve decided that mini-splits are high-end specialty work, and price it accordingly.
You could easily buy a low-end minisplit online for ~$300, but professional installation could cost $3000.
Refer tech here. The issue is nobody wants to waranty or maintain heatpumps. They seem really similar but they are wildly different from a standard central air system.
HVAC and refer techs tend to be fans of controls which are big dumb and mostly if not entirely mechanical. Heat pumps are very much not that. Everything is electronically controlled. They use electronic pressure sensors and electeonic temp sensors to electronically control the speed of a variable speed compressor and variable speed fans. Nothing on a heatpump runs at a steady state and it makes the already fairly complex mechanics of the refrigeration cycle harder for techs with a less intuitive understanding of it.
Theres also the fact that debugging circuit boards is not something HVAC techs do. Generally they find the bad board and replace it but heatpumps have so many interacting boards that it is difficult for even the equipment manufacturers to tell which one is causing the issue. I’ve literally had mitsubishi (the gold standard for heat pumps if anyone is wondering) tech support tell me “well we’ve narrowed it down to one of 2 boards so just replace one and if that doesn’t fix it then replace the other one” like they weren’t talking about $600 parts.
Plus you also have a lot of manufacturers that are still just plain bad at building the equipment. I remember one cooper and hunter indoor unit where I was struggling to figure out how I was supposed to get to the fan motor to replace it so I looked at the manufactures info to see what they recommended. Their instructions were to literally bed the STILL CHARGED indoor coil outwards to make room to remove the motor. Yes, physically bending a charged refrigeration coil was the only way to replace a pretty standard wear component.
Along with all of that, all of the components are proprietary. In a standard AC system you can find all sorts of generic components to replace whatever you need to. With heatpumps the components are only available through that manufacturer and only for as long as the choose to keep selling them.
That’s not to say heatpumps aren’t great. They are great. I recommend them to customers all the time. But they definitely have their issues and I can understand why a lot of outfits want absolutely nothing to do with them. They also have places where they should 100% not be used (ie whoever sold a heatpump the the fucking flour mill I’ve been working in needs to be shot).
I’ve thought about getting one, but I hear they have major mold and mildew issues.
How would they be any different than a standard AC coil in that regard?
Regular use of Coil cleaner is the key here.
This unit supposedly has a ‘sanitize’ setting that will use cycles of extreme hot and cold to automatically kill anything growing in the inside unit. Haven’t tried that out yet, but it sounds promising.
And if that doesn’t work, I guess I’ll just manually clean it and maybe spray some bleach inside if it starts getting bad.
There is a dehumidify setting, and we mainly use that because it uses less energy than the AC setting, plus we live in an area of high humidity so it cools down our place amazingly.
The only time I’ve seen mold issues is in flats that were converted from big old houses (big!) With zero ventilation (plenty of examples where our kid lives)
They actually have fewer issues because you can just reverse the cycle and cook any mold off of either coil. As it is most centeral AC coils are just permanently moldy without most people knowing it.
