Bryan shows how air conditioning gauges work. This is HVAC training for beginners to the HVAC/R trade, not homeowners or those who aren’t properly certified. We cover the basics of how an air conditioning and refrigeration manifold works and how we use it in the field.
The gauges are on top of the manifold; the manifold refers to the actual assembly with the gauges, hoses, valves, and sometimes even a sight glass. We use the gauges to help us determine saturation temperatures and pressures for various refrigerant types; there are low-pressure and high-pressure gauges. We have to calibrate the gauges to atmospheric pressure (hence PSIG: pounds per square inch gauge).
The hoses can be screwed onto parks to keep them from being contaminated when the manifold is not in use. However, it’s best to calibrate your gauges with the hoses open to the atmosphere. The manifold has a high side (usually red) and a low side (usually blue). The center port (usually yellow) is for charging and recovery.
The handles have nothing to do with the gauges themselves; handles merely open valves that allow communication between the center port and the high or low side (depending on which handle you turn). In most cases, you will only open one handle at a time (unless you’re feeding refrigerant from the liquid side to the suction side or vice versa). Don’t over-tighten the handles!
Normally, you will just use the center hose and one side depending on if you’re charging the system (middle to low side) or recovering from it (high side to middle).
Manifold hoses may also have core depressors, which depress the Schrader cores inside service valves and allow the flow of refrigerant. Some gauges also have a sight glass, which allows you to watch the refrigerant flow when you’re charging or recovering refrigerant.
There may also be a hook at the top of your gauge manifold, which allows you to hang the manifold from your equipment. (Make sure you don’t poke the hook into your condenser coil!)
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Thank you for the explanation
How do you feel about the ones that dont have a sight glass but instead have a little schrader valve on the yellow center fitting for burping air out of the line?
This was an excellent summary of how to use this. Thanks a lot
Awesome video! I know waaaay more now! Are you a teacher, 'cuz if you aren't, you should be. Thanks!
Do you need a 608 license if you just wanna buy 134a to get high?
Outstanding demo!! Finally, someone has explained the fundamental questions I had on "how" refrigerant flows through an AC manifold with respect to the High & Low control knobs. Well done and thank you!!
THANK YOU SIR…for the Best Explanation of the A/C Manifold/Gauges!!!
You say not to do this as a home owner but I can't afford to pay 300 every 2 months with a leaking condenser so propane refrigerant it is wooo
I've already got a guage set from automotive just gonna make an adapter to home ac fitting and
Charge my gas pack full just to get me through the summer till I can afford a new unit come next spring
Just bought this house
Is it bad to open both the high and low side valves up at the same time while the system is running? I realized I had both open at one point and it seemed like it made made my pressures shoot up pretty high but idk if it hurt anything. It seemed like it made my pressures read inaccurately too
Thank you, best explanation.
In fact, I did my read, with out cert. you can do your own home with 410 and its completely legal… you can NOT do R-22 at all.
However you can NOT do a friends home with 410.
I was trying to say to add refrigerant you would open low pressure side valve on the manifold but i opened the high pressure side instead for 30 minutes and it did not add any refrigerant. Now my concern is did i damage my ac system?
Thanks for the video =)
Thanks a lot man, this video makes me happy, thumb up
That was an excellent video. You made some great information and I appreciate for that! Keep it up! Here is an video on Testo Measuring Instruments Manifolds https://www.youtube.com/watch?v=z9gxnGAfyTg
allow communication lol. i think you meant flow
Super
hate that lame disclaimer do not use it unless you're a trained professional. I get you're trying to protect folks but it also sounds like you're looking to protect jobs for the industry. IMO, if you're diligent with safety and did your homework, you're good to give it a try. Definitely safe if you've been taught by someone too. That's how I learned plumbing and electrical and people always say the same thing. All that said, obviously try at your own risk so do more hw and be extra careful if you want to lower your risk. I'd rather be told that then to not try at all unless I'm a trained professional. =)
Thanks for the video
I'm a home owner and I'm doing it anyway…lol
I charged my system in my car today and it was blowing 50 degree air for an hour with 100 degree temps outside at 30psi and I went to close down the manifold to disconnect and accidentally opened the discharge side with the suction still open. Suction pressure skyrocketed and now I only have 70 degree air coming out and 50 psi on the suction and about 275 to 300 on the discharge. The discharge side is pretty much in spec with my service manual but the low side is now way too high and I don’t have cold air anymore. What do I do?? Will the pressure balance back out as the system runs? Also is it possible I damaged anything? It took me about a minute before I realized why my numbers went wacky. Also this is a very informative video and I learned a lot in just a few minutes. Any help is greatly appreciated!!!
You answered the exact question I had about the hose direction. Thank you!!
I just started my first Hvac job I told them I had 5year experience got the job getting paid really well but I actually don’t have 5year experience know very little. Hopefully they don’t find out.
Terrible instruction! I hope some suckers aren't paying you.
My yellow hose for the MGS has a sort of valve inside one of the hose ends. The instructions do not mention which way this valve is supposed to face ( gauge set or refrigerant/ vacuum pump side)
Any ideas?
Should have shown zeroing the low side, vacuum discussion and values on the low gauge. The infamous 500 microns…
I'm improperly certified.
Do you always recover refrigerant through the high pressure side??? So you're saying you put in refrigerant on the low side and recover on the high side, is this so for all refrigerants should they be put in on the low side as a vapor, and recover on the high side as a liquid. What about 410-A does it go in as a vapor or does it install as a liquid on the high side???
Excellent
Would you disagree with the idea that most licensed HVAC contractors are reluctant to work on the installation of the low cost mini-split units sold by the "big box DIY stores. Seems like HVAC contractors service and install only the specific big name HVAC manufacturers they prefer.
Do you know where I can buy the "parks" fittings? I've been searching everywhere online and can't seem to find any.
Still trying to save some money to buy the vacuum pump. Any alternatives to share ?
In my country most aircon technicians come from india. Yhey dont appear to have any certification at all yet they charge exorbitant prices. I am planning to do this on my own.
Thank you for this Sir. I wish you had a video on how to charge an aircon
Great video, thanks man.