Don't Check Refrigerant in Mini Splits. Here's Why!

Ever had an HVAC system low on refrigerant which some folks call freon? In this video, Joshua Griffin shares why you can't just easily connect gauges to a ductless mini-split system as you would connect to a typical air conditioner or heat pump. This goes for inverter HVAC systems as well. Connecting gauges to a system of these types that have to ability to ramp up and down does not allow you to do full-capacity superheat and subcool measurements. Therefore, you won't be able to tell if the system is properly charged without properly weighing the refrigerant in.

********Our favorite products?********

Griffin Air and Joshua Griffin have partnered with Daikin on multiple projects. FTC requires disclosure of these relationships due to the compensation received.

-----------Chapters-------------
0:00 Intro: Can you check refrigerant on minisplit?
0:42 Exceptions to rule
1:00 How to check properly
1:54 You don't want gauges connected
2:52 Error notifications
3:11 Outro

#minisplit #ductless #refrigerants

[beltwesty]

Pre EPA Hvac rules 1980s Ancient mini spilt history: the units i saw in Singapore Toyko and Thailand had R22. They had both high and low pressure taps on the outside unit. The expansion valve was Inside in the Inside unit. This scheme sometimes added noise of the metering valve.

Todays mini spilts I own are R410a. The metering valve is in the outside units. There is NO high pressure tap to measure the high side pressure. Both lines are on the low side on most all modern mini spilts. That is why both lines are insulated.

When a modern mini spilt is low on charge in Cleveland the smaller line usually frosts over. So the poor homeowner is trying to cool all of Cleveland than the inside of his John and Janes house.

The problem a HVAC repair guy has is the lay public thinks there are 2 pressure ports to check what is happening on a mini split.

Also the HVAC repair person has no clue if the lost 10 oz of R410a happened over 7 years or 7 days.

Most of the time the leak is in the inside unit or the flare fittings.


.

[gultra]

I'm glad I'm nearing the end of my HVAC career instead of just starting out in the field. Life was much simpler before all the modern technology and when everything was 22, 12, or 502.

[ryanbrown]

2:43 The same thing happens with conventional systems too. If it’s a maintenance call you shouldn’t have to put your gauges on a system if amp draw, delta T, and everything else checks out good.

[Robshamsterteam]

Couldn’t you just turn off the system for like an hour and then turn it back on and obviously it’s going to want to be at full capacity to get that back up and then you could check then I mean considering that at that point the system is probably gonna be running at 100%

[btricopter]

Sad but mostly true. There are too many variables to diagnose properly for it to be cost effective for the homeowner. Put it on the curb and install a new one. It will be cheaper in the long run than have a hvac tech to work on it.

[paulyboy]

The government must be involved with the HVAC companies My unit goes out, they don;t have r-22 to replace the Freon, so you have to buy a new unit with the new Freon type. So you are forced to replace your old unit. What a scam by the government and the HVAC companies. I bought a mini spit unit and my son and I installed it in 3 hours.They wanted $7500, payed $700 and did it myself. I am ripping off low life HVAC companies I hope.

[luisrivera]

I completely disagree with you. Sure you can tell if it's low on refrigerant, just by throwing your gauges on any mini split. I've been doing it since they first came out.

[guuuuustaf]

As a hvac refrigeration technician, I can verify that what this video tells you is. SPOT ON. He knows for sure what he talks about.

[oliverlewis]

I don’t put my gauges on most systems whether conventional or mini split. I first start by taking temperatures and if my temps are off then I start looking at other things before connecting gauges.

[wileymarmt]

While technically correct about weighing refrigerant, modern mini-splits have specific instructions on how to check refrigerant without removing it (I.e. “loading it up to capacity”).

Eventually one of these “not my install” HVAC companies are going to figure out how much DIY install money is left on the table and start making a butt load of cash!

[rayl]

I don't quite understand - why would say a 3 ton mini split have so much less refrigerant than a 3 ton central heat pump?

But having recently (like 2 wks ago) upgraded heat pumps, I do like the technology. For once, without redoing ducts or other invasive modifications, my two levels are within 1 degree F (sometimes within 0.2 degrees!) of each other thanks to inverter technology. Used to be a ~3 degree difference.

[nevermind]

Very true, but you can set the temp control down low and verify performance by measuring the temperature drop across the indoor coil. That would give you a pretty good idea.Also look things over good for traces of oil. Nice video. thanks

[renecuevas]

30 yrs in this field I use Gauges as less as possible. Loose Ref is a possibility when install gauges specially on hot days where pressure is high 450 normal on 97 degrees summer time Griffin is rite DUY need stay away from Gauges. 5 yrs of School here n 30 plus in fieldwork trust me

[e.balsamo]

Great Video Thank You for sharing, I have a question for you, I have a Mitshibishi muy-gl18na-u1 18BTU 20.5 seer mini split, My system will not ramp up, It blows cold air inside, The outside unit I have a Error Code 3 blink then pause 2.5 seconds, its under warranty still, A diamond perffered company replaced the Board, and compressor, I installed all new sensors, I removed the blower wheel and cleaned the inside unit back to new looking, No matter what I do system will not ramp up, You can hear the compressor ramping up but the fan motor stays in the same speed. Any Ideas? Maybe the Fan motor going bad?

[brittoncorbin]

Stop the fear tactics. It actually is that simple. Put mini split in high AC, pressure should read between 117 and 120 psi.

[rogerbritus]

Can anyone tell me if the Pioneer mini splits have this self-diagnosis feature?

[mikeholman]

I'm sure this is the correct way to do it. However, someone who hasn't got a recovery tank or a scale doesn't really have this option without shelling out hundreds of dollars. It's going to cost more than the compressor is worth for me to call a tech. So I fumble forward and add refrigerant.

[paramboytv]

Check refrigerant with super heat or sub cooling and saturation temp. All other technique are good but take too long

[independenttntn]

As homeowner who does ALL of their own work down to and including changing out electrical panels hot (YIKES!) I love you're channel and am so glad I found it. GREAT INFO!

[tomschmidt]

This isn't my day job so this is an interesting factoid. We installed a LG minisplit inverter system, two compressors 6 indoor units a couple of years ago, nice piece of info to take into consideration especially with R410a phaseout.