HVAC Gauges, Analog vs. Digital vs. Probes

Bryan with HVAC School goes over some of the common differences between analog gauges, digital manifolds (with the Testo 550), and probes. We examine the benefits of each and discuss their ideal uses.
Many people learn on an analog manifold, as you have to be able to calculate superheat and subcooling on your own with a line temperature clamp. So, the analog manifold is a good teaching tool; by comparison, the digital manifold gives you the answers and doesn't make you familiarize yourself with the math required in HVAC work. The analog gauges also show saturation temperatures for a few different refrigerant types.
However, analog gauges have low resolution, and it can be difficult to get exact measurements in the field. On microchannel condensers and critical-charge systems, those mild inaccuracies can actually be pretty significant. Line temperature clamps must also be calibrated separately and may use K-type thermocouples, which tend to be less accurate than the thermistors used with clamps for digital manifolds.
It's much easier to zero out digital manifolds, as you press a button with your hoses open instead of removing lenses and adjusting needles manually. Digital manifolds can tell you your evaporator temperature (EV) and condenser temperature (CO) all on one display. You can also select the refrigerant type (reducing the probability that you're looking at the wrong refrigerant scale) or go into superheat/subcooling mode. Digital manifolds also tend to be a bit more accurate, as do the line temperature clamps that connect to them.
You can also use wireless probes for non-invasive testing. They have a similar level of performance as digital manifolds, but they're smaller and reduce the risk of refrigerant losses through hoses. However, you have to add a tee for charging and recovery, as you can't pull through the probes themselves.
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[@TheRouteShow]

Make a video on correct method for cleaning split Ac indoor and outdoor unit(wet method ) .. There is not proper video on this topic... Your channel is great..big fan of ur channel from India...

[@jgt5642]

buying a analog to start but you answered questions i didnt know i had, will purchase digital in the future. thanks.

[@adame5238]

Analog is a must for beginners. After that, it's personal preference.

[@HVACRTECH-83]

I just got the field piece charge and air wireless probe kit and must say I wish I didnt wait so long to bite the bullet on this kit. I've never used the testo ones so cant say which are better but this is a serious game changer guys. I have had the sman480v for about a year and love it too but honestly dont see the need for it anymore. Love the probes with the measure quick app. Had some connection issues with the fieldpiece app but no problems at all w measure quick

[@ohboah320]

Wow! A Bantom gauge! I thought I was the only person that still had one! I have the 4-valve version.. So compact for back in the day gauges.

[@BuckFu]

In my experience digital gauges require more calibration and maintenance. I’ve had a ton of problems with the sman360, there was an instance where the sub cooling and superheat calculations were so far off from recommended charging pressures& temperatures I have no doubt if you follow the fieldpiece built in calculations that the system will definitely be overcharged.

[@corvairbob65]

using the analog low side gage what would i be looking at the see 500 microns or 000 microns in a vacuum in the neg part of the scale how many in of vacuum? thanks

[@dhidhat]

Can you use the same manifold for different refrigerants? Do you need one set for R32, one set for R410a, etc?

[@ralphlaurencastro]

What multimeter do you use now?

[@1guysmilely]

Is there an email to contact you for questions?

[@HighGrade592]

Yes and carburetors were great too in my daddys austin cambridge Fast forward 2018 turbocharged Fuel injection ect ect ect And we are still getting from point a to b We are only doing it different AND MORE EFFICIENT

[@racegrubb2152]

I haven't switched from analog yet, only because im worried about the life spand on it and whether or not they give problems or not. I don't want to dealing with it messing up all the time while im troubleshooting. Anyone thats been using them for a while please let me know, im also worried about them getting wet and using them on a watersource hp in a nasty crawl space. Any feedback would be great! Thanks, are those testo 550s good? Thanks

[@murkyturkey5238]

I have the probes and everything works good except the pressure probes for checking charge 😂 I’ve had them for a year and I’m very careful with them but they will no longer connect to my phone so idk if I can say it’s worth it or not. They are very accurate and very fast to use especially for tight spaces like an rtu where you just need to check charge and have to put the panel back on while it’s running

[@murkyturkey5238]

Field piece probes and yes they’re waterproof I believe

[@channelcatchaser9426]

I love my 550

[@dtrrtd774]

Is there any design changes between the 550 model and the newer 549? Been trying to see what the actual differences are but they seem to be the same.

[@HVACS]

549 has no temp clamps

[@dtrrtd774]

@@HVACS is that simply that it's not supplied with the temperature probes, but the capability is still exactly the same? I just thought it would be odd that they would use a different model number if the actual unit is identical. That explains why the number is lower, I guess. New! but not improved! :D

[@dtrrtd774]

I just saw a chart comparing the 549, 550, 557, and 570, and along with the 549 not including the temp clamps, it apparently also omits Bluetooth media.testo.com/media/42/4b/300d70a3a4bd/Produktvergleich-EN.pdf But then I see descriptions of the 550 being non-Bluetooth, so maybe there are multiple variants of the same model to maximize my confusion- ;) Does a Bluetooth feature add any value to things in actual use?

[@BERESHIDA2008]

the are exactly the same, except that the 550 has bluetooth, and the 549 doesn't

[@dtrrtd774]

Have you found the Bluetooth feature to be useful for this application?

[@leealtmansr.3811]

Get rid of any hose. That is where problems start. Wrong refrigerant or air in the hose or you rob refrigerant. If we get rid of hoses there are less problems afterwards. So the new short hoseless probes are even better.

[@zacharyburkett7829]

I believe I should keep my smarts and not give them up. If i only read something it’s ok but if i calculate every time , my brain will retain its coherent responsiveness.

[@runningcoyote3897]

If it ain't broke don't fix it. Anolg is the best choice

[@runningcoyote3897]

@Eric M I use analog clamp on meter at times, but a mercury thermometer? Don't be ridiculous all I'm saying my YJ gauge gets the job done every time.

[@runningcoyote3897]

@Eric M year I know what I wrote lol you do realize I'm only taking about gauges right?

[@runningcoyote3897]

@Eric M man you really are pressing this subject huh? You're right about the uncertainty, but as long as you're 1 or 2 degrees off subcooling there's no problem at least in my experience so far.