Garage too hot; Portacool versus mini-split A/C system? - Page 5 - PeachParts Mercedes-Benz Forum

barry12345 · #61 09-22-2019, 01:08 PM

Even many of the hvac guys are taking too many shortcuts. In a way it is cheating the customers. Even when they know better.

JHZR2 · #62 09-22-2019, 01:13 PM

Quote:

Originally Posted by funola

Question for those who diy-ed their mini splits: Did you forego the factory warranty or were you able to find a contractor to vouch for your install and register your unit?

I skipped it.

Years later it still works great knock on wood. But I did buy quality tools and was careful with my work.

If I had to evacuate the system in the future it could be an issue but otherwise hoping for the best. The savings I had for a pretty simple instal would pay for two more new complete units.

JHZR2 · #63 09-22-2019, 01:18 PM

Quote:

Originally Posted by funola

Example: one contractor says most of the leaks in their experience through the years of mini split installs is in the evaporator, so they braze the connection at the evaporator instead of using a flare. When asked if they purge the lines with Nitrogen while brazing (to prevent oxidation), their answer was no!

I asked another contractor if they pressure test with Nitrogen and the answer was no! They just do a vacuum, if no leaks, they let the refrigerant out! Not going to name names but this was a Fujitsu Elite contractor.

I can see the logic to brazing, as dependig upon what direction you want the line set I think it may be easier to cut off the connection on the evaporator, have a much shorter lever arm there to stress it, then just pull and secure the line set where it needs to be.

Don’t know enough about precautions on brazing and gas use, but if the systems are line mine, the line set is not lrechsrged, the condenser is. So one could pull hard vacuum on the evaporator afterwards fwiw.

funola · #64 09-22-2019, 01:54 PM

Quote:

Originally Posted by JHZR2

I skipped it.

Years later it still works great knock on wood. But I did buy quality tools and was careful with my work.

If I had to evacuate the system in the future it could be an issue but otherwise hoping for the best. The savings I had for a pretty simple instal would pay for two more new complete units.

What tools did you buy? Still have them? If I decide to DIY, do you want to sell them?

funola · #65 09-22-2019, 02:00 PM

Quote:

Originally Posted by JHZR2

(.................)

Don’t know enough about precautions on brazing and gas use, but if the systems are line mine, the line set is not lrechsrged, the condenser is. So one could pull hard vacuum on the evaporator afterwards fwiw.

Purging with Nitrogen when brazing is to prevent formation of carbon bits inside the copper line that could flake off and clog small passages.

I think most line sets are not pre-charged except MrCool DIY kits that Vstech mentioned earlier.

JHZR2 · #66 09-22-2019, 06:49 PM

Quote:

Originally Posted by funola

What tools did you buy? Still have them? If I decide to DIY, do you want to sell them?

All yellow jacket made in USA tools. Flaring tool with brake, reamer, good gauges, US made vac pump. SK crows foot to torque properly. Plus nylog.

I still saved so much compared to the HVAC scam artists that way overcharge on these things around here.

The pump is great for auto work, gauges may need some day, ditto for flaring tool. Probably wouldn’t sell but I’d consider a loan if terms were favorable.

Quote:

Originally Posted by funola

Purging with Nitrogen when brazing is to prevent formation of carbon bits inside the copper line that could flake off and clog small passages.

I think most line sets are not pre-charged except MrCool DIY kits that Vstech mentioned earlier.

I think most systems that have brazed connections have an inline filter/dryer.

Never looked into precharged, I used standard line sets on both of mine. Only difference being the type of insulation on them.