4 ms·

> Where are the refrigerant lines, how did they run them from compressor to evaporator? Look at this image from the blog post showing the post install view: h

by pwg 6y ago

> Where are the refrigerant lines, how did they run them from compressor to evaporator? Look at this image from the blog post showing the post install view: https://www.techprowd.com/content/images/2020/09/image-24.png https://www.techprowd.com/content/images/2020/09/image-24.pn... Notice on the left edge there is a large white "pipe" running from the evaporator unit down to a hole in the wall (the hole was already present and visible in other photos). The refrigerant lines are running inside that white cover and through that hole to the outside unit. > I thought the biggest issue with AC self install is filling the refrigerant and sealing those lines. As for the refrigerant fill, yes, that is the part of the work that most DIY folks will not have the equipment to perform. The evaporator and compressor units for most of these mini-split units come prefilled with refrigerant plus enough extra for X length of tubing (I forget the length X at this time). The install basically involves installing the lines, evacuating them (refrigeration grade vacuum pump needed here) and then opening the shutoff valves in the two units to release the already present refrigerant. Since most DIY's will not have a refrigeration grade vacuum pump, and are unlikely to be able to justify the several hundred dollars for one for a one-off install, this is the point where the DIY'er would need to call a professional for the final completion of the install.

gcds 6y ago
In japan there is also way to rent tools, next time I am doing it by myself it costed almost third AC to get 2 installed... When materials and rent didn't even cost more than 1 install cost
Scoundreller 6y ago
> refrigeration grade vacuum pump needed here My understanding is that some of the DIY units had a built-in vacuum pump for this step. Edit: never mind, I think I’m making stuff up in my head. But I could see it being a feature in the future. What makes a vacuum unit “refrigeration grade”? Other than recovering what you’re vacuuming if you’re doing maintenance instead of a first install?
- pwg 6y ago
  Generally what makes it 'refrigeration grade' is the level of vacuum down to which it can pull. Here are some examples of refrigeration vacuum pumps: https://www.grainger.com/search/hvac-and-refrigeration/air-conditioners-accessories/air-conditioning-chemicals-tools-and-accessories/air-conditioning-and-refrigeration-tools/refrigerant-evacuation-pumps?ts_optout=true https://www.grainger.com/search/hvac-and-refrigeration/air-c...
- jcrawfordor 6y ago
  Rated to pull high vacuum, <500 micron at the most. You can get such pumps very cheaply, the issue is usually the volume on them - when I tried using a very cheap ($60) one it took a very long time and kept going into thermal protect on the way down, and that was with a small system. Refrigeration techs use vacuum pumps that both move a large volume and can do very high vacuum and that's pretty expensive, although not insanely so - I see one from a popular HVAC brand for $500.
bri3d 6y ago
Some mini-splits (MrCool DIY series) also come with the lines precharged using quick-connects. These require no professional tools or equipment, with the drawback that installation is limited to the exact length of line provided.

by pwg 6y ago

gcds 6y ago

In japan there is also way to rent tools, next time I am doing it by myself it costed almost third AC to get 2 installed... When materials and rent didn't even cost more than 1 install cost

Scoundreller 6y ago

> refrigeration grade vacuum pump needed here My understanding is that some of the DIY units had a built-in vacuum pump for this step. Edit: never mind, I think I’m making stuff up in my head. But I could see it being a feature in the future. What makes a vacuum unit “refrigeration grade”? Other than recovering what you’re vacuuming if you’re doing maintenance instead of a first install?

pwg 6y ago
Generally what makes it 'refrigeration grade' is the level of vacuum down to which it can pull. Here are some examples of refrigeration vacuum pumps: https://www.grainger.com/search/hvac-and-refrigeration/air-conditioners-accessories/air-conditioning-chemicals-tools-and-accessories/air-conditioning-and-refrigeration-tools/refrigerant-evacuation-pumps?ts_optout=true https://www.grainger.com/search/hvac-and-refrigeration/air-c...
jcrawfordor 6y ago
Rated to pull high vacuum, <500 micron at the most. You can get such pumps very cheaply, the issue is usually the volume on them - when I tried using a very cheap ($60) one it took a very long time and kept going into thermal protect on the way down, and that was with a small system. Refrigeration techs use vacuum pumps that both move a large volume and can do very high vacuum and that's pretty expensive, although not insanely so - I see one from a popular HVAC brand for $500.

bri3d 6y ago

Some mini-splits (MrCool DIY series) also come with the lines precharged using quick-connects. These require no professional tools or equipment, with the drawback that installation is limited to the exact length of line provided.