Mini-Split Heat Pump: Nitrogen Pressure Test

In this video, I'll be doing a pressure test for leaks using nitrogen on a mini-split heat pump.

Thanks to everyone for watching!

[JPNR]

Of all vids out there, this was the most straightforward, easy to understand and had no nonsense to waste time.
In 11 minutes, you've covered everything I needed to refresh my memory.

[mikemandus]

Great video and good info. Only 1 issue, at 4:00 he forgot to mention he isolates the tank from the test by closing off the low pressure (blue) valve. You can see him close the valve off.

[chicchoc]

great video. I learned to do this as a DIYer from older youtube videos which were helpful, and allowed me to install 7 minisplits for myself and family members, but your videos are much better and more clearly explained.. i have another 2 units to do soon so i thought I would brush up.. Glad i found your videos.. you will allow many other DIYers to tackle this as well and save the $1000-2000 they would pay to have a pro do the work in a day... and although some pros are top notch, many others do not nitrogen test nor take the care that a caring DIY homeowner will. Subscribed.

[balokurd]

I've never waited so long to find a leak ! Just a little tip : when you finally release your nitrogen outside, you can do it in one shot by quickly opening your valve, so it's gonna kick all the crap inside more efficiently

[EXOVCDS]

I'm still watching and haven't read the comments... I'm at 4:43 . Could you close the valve on the source tank and watch for pressure drop? A small leak might not drop the needle if you have a constant feed of gas. Back to watching.

[youarehere]

That's as good as it gets! You explain it very well. Hopefully people are paying *close* attention because after you let refrigerant into the lines through the low-side of the gauge set and adjust the regulator valve to get the line pressure to 200 PSI, you *close off* the low-side valve of the gauge step, which cuts off the feed of nitrogen from the N2 tank, otherwise that would overcome the pressure lost by any leaks and be self-defeating. You don't mention that's what you're doing at that step though, you just crank the gauge blue (low-side) valve closed. and that's a really important step! My Daikin outdoor compressor installation manual says to pressure test at 550 PSI, but don't exceed that. Also recommends holding the pressure for 24 hours but I think it says minimu of 1-2 hrs.. Not sure if all mini-splits can handle 550 PSI, but from what I understand r410a generally reaches a pretty high pressure in mini splits. Anyway the higher PSI test might catch some leaks lower pressures won't, so why not?

[wyattoneable]

When everything is completed I want to see you in the air conditioned garage enjoying the cool air. Things are looking really good Terry.

[felizdao]

If you don't shut off the nitrogen tank, the pressure will keep up 200 psi until the nitrogen tank is depleted. Therefore, this is only good to check for leaking with bubble test or with other leak test devices.

[stuzman]

I did close the valve on the manifold, but I didn't mention it. It's around the timeline of 4:00. Have a great day!

[unionseen]

Good videos.. 1) He did not mention it, but he did shut off the supply of N2 to the system by turning the low pressure valve off...if you fail to do this the bubble test will still be valid, but the decay test won't be as N2 will still be supplied from the regulator. 2) You could purge the full line set and inside unit by waiting to tighten the upper flare fitting while you let some N2 into the system.. to remove air and moisture. This would give you the best decay test (less effected by temperature changes) I'm no HVAC expert just a Mech Engineer about to install a Mini split.

[reginaldsotero]

this is the neatest, well-disciplined, professional installation ever, you rock the hvac industry Sir!

[salvatoregiovanni]

Very well done video. You are slow and methodical about the way you explain things so anyone can understand exactly what you’re doing. One tip, if this is indeed an r-410a heat pump (not an AC only system), your lineset’s flares will indeed see pressures in the 400-500 psi range in heat mode. So if you do a nitrogen pressure test, a higher psi test than what you did may show flare leaks that a lower test pressure may not.

[kerry]

Excellent video, thanks for sharing!! Now I need to get my HVAC convinced to do a proper pressure test since I have had past issues with leaks. Id like to see a prolonged length of wait time, more then 15 minutes in my case

[josephgraham]

Sir you are a great instructor I have much more confidence on installing my own mini split dual zone after watching all your videos. Thanks for taking the time and sharing

[tesos]

While you were at it, I would have cracked the high side nut on the outdoor units and purged the line completely with nitrogen, then later when you get to vacuum testing you are only dealing with nitrogen in the lines.

[theblaze]

Looks like you did not close the bottle after getting the pressure you wanted. Maybe it’s safer to close it. Thanks for the video

[doddgarger]

These things run in the 400psi range I would take advantage of having the ability to go at least to 400psi on the pressure test

[spelunkerd]

In a heat pump, I believe flow is reversed when switching from heating to AC. So, the high side must become the low side. In our home heat pump the two lines have different diameters, usually the low side is big diameter line and the high is small. If flow is swapped every season, why don't they have lines with the same diameter? Won't a big diameter high pressure line cause some kind of problem?

[cwarbucks]

Great video, easy to follow, good camera placement.

[mid-hudsontoolworks]

Very informative, thanks for posting this. Any chance you could note part numbers for the equipment you used to pressure test this mini split?