It needs to be completely evacuated. Air and moisture will cause acids in the system. Plus, that air reduces the efficiency by a large margin.

They botched it. There's no such thing as a "high tech" system that doesnt need an evacuation.

 

Thank you for the prompt response HVAC_Marc. My challenge will be to get those guys back out here to do it correctly.........

Will just evacuating the system be enough to remedy the situation? or does the oil/air/moisture chemical reaction happen rather quickly so the acid is already in there? System has been running for 6 days.

 

they need to recover the old refrigerant, evacuate the system to the micron level in the book (around 250-500 usually), and install new refrigerant. They can add acid-away (rectorseal) to the system and it will neutralize any acids already present.

 

Thank you again. Makes sense.

 

low bidder?

craigslist?

 

Pull the charge
Triple evacuation and weigh in a new charge.

BTW
I wouldn’t let the first bozos do it the second time!

 

Nah, it was a local, well-established company that had good recommendations & reviews on the "Next Door" app. This was so straight forward I thought no way it could get fouled up. In my business, I always say "it's hard to get good help"... i guess the HVAC business is no different. I didn't bother getting bids, got one quote, it was higher than I anticipated, but seemed reasonable for the time that would have been req'd to do it right.... it wasn't reasonable for a 15 minute cluster. Maybe the business owner will make it right.....
-LR

 

I always say "it's hard to get good help"... i guess the HVAC business is no different.
-LR

You have no idea!!

It's probably worse than what you think.

 

So sorry you got stung. As stated above, they need to pull the entire charge of 410a and air, evacuate, and weigh in the proper charge with virgin 410a refrigerant. Running it as is will result in premature failure.

 

What about moisture from the air which is now in the POE oil? Going by the book, the oil should be removed and replaced, then evacuate the system, and then weigh in virgin refrigerant

 

Do we actually know if it has POE or the the newer PVE in it? The PVE will release the moisture under a vacuum.

Sent from my SM-N910W8 using Tapatalk

 

The data sheet says it is "Ester Oil VG74" I cannot find info on this specific oil on the interweb.... I have no idea if this is PVE or POE.
-LR

 

My minisplit install instructions call for a 3 level evacuation after a 1 hour minimum pressure test with zero drop.

System has to hold below 500 microns for one hour minimum...

I'm willing to bet the install instructions on your unit require similar procedures...

 

Installation manual called for:
"Run the vacuum pump for at least 15 minutes, or until the low pressure gauge reads -76cm Hg (-100kPa or -30 in Hg)"
---- Looks like the manual isn't too precise in that regard.

The manual also says to wait for 5 minutes to check for pressure change.
--- fairly lacking compared to what you mention.

Apparently these fools couldn't even follow the half-ass instructions properly...............

UPDATE:
The "Service Manual" calls for 30 minute evacuation to 500 microns... that was for initial installation

For evacuating the entire system, it calls for "evacuate for approximately 1 hour. Confirm that the compound meter indicates 0.1Mpa (14.5psi)"

 

I wouldn't worry about it. Due to the low cost of the equipment. Seriously if it fails. Just go out and buy another. Things disposable anyways. :grin2:
And next time buy the install and unit from a contractor. So they treat it like one of their own. I don't agree with the service you got. But...Just say'n!!

 

In an ideal world with unlimited budget and a wife not watching my spend, I would have someone do it all.... for 3x or 4x the price I am into it for. This was a 'luxury' spend for me, just to extend 'workshop season' and allow me to do some wood work and home improvement projects year round in the garage.

I had to run the refrigerant lines and wiring in buried conduit.. I trenched by hand around 16', installed my own 3" conduit for the piping, conduits for the wiring, etc. Pulled the lines thru the conduit, ready to terminate. Pulled and terminated all the electrical. My foundation for the outdoor unit is better than any residential AC install I have ever laid eyes on - compacted subgrade, stacked blocks glued together for mass, etc. The wiring from disconnect to unit is in watertight flex. The refrigerant lines are covered in a custom fab rain shield so UV will not degrade the insulation/cover. My 3" conduit bank is completely sealed and covered on both ends to prevent water ingress. I had to build a fake wall in the garage to mount the indoor unit - it is not on an exterior wall. Drain line is routed separate from the refrigerant and power lines..... bottom line I could not afford to pay anyone to do all that work up to my standards. The techs even commented that it was a really nice install... too bad they were too lazy to do the same.

I haven't reached out to the installer yet - I really appreciate the feedback and info from you guys. It will give me a good 'argument' to get him to come back and do it right.... but at the end of the day, KB Cool, you may be right. I can spend another 300 or 400 to have someone do it right or just run it till it breaks and buy another 5 or 600 outside unit + commissioning labor.

Thanks again for all the feedback and advice. I'll be sure to post a final resolution when I have one.

 

He won’t come back!