Mastercool or Yellow jacket ac gauges

GON

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Inquiring who makes a better top of if the line ac gauges, Mastercool or Yellow jacket?

I have a time of ac work to do, and currently have a Harbor Freight a c gauge. I won't to make sure I have the best ac manifold gauge set, as I am a novice with ac work, and don't want marginal.gauges to impact upcoming work

I suspect high quality gauges are actually a cost savings. Future work included compressor replacement, vacuum, etc

Any recommendations, Mastercool or Yellowjacket?
 
Most home HVAC pros appear to use Yellowjacket analog gauges or Fieldpiece digital gauges. However, I have owned a Mastercool gauge set for ~18 years and it has been flawless. The only modification I made to the Mastercool set is to replace the original R-134a quick disconnect fittings with Robinair QD fittings which have the knobs that screw down to depress the Schrader Valves.

I highly recommend a Robinair vacuum pump as they are as good as they get.
 
I'm gonna vote Yellow Jacket or Robinair. In my VERY limited experience Mastercool has gone the way of FelPro, Moog etc. I had a Mastercool gauge set I returned because I swear it was defective and their tech support was condescending and dismissive. I went Robinair and it's really nice
 
I think unless you seriously going to do (and trained) AC work as part of your day job it's better left to a Pro with the AC machine that can evacuate the system and save & filter the refrigerant.

The systems need to be filled by weight not pressure.

An electronic refrigerant sensor is needed and costs a few hundred $$.

So if the pressure is low and you think it needs a can of refrigerant you really need to evacuate the refrigerant, vacuum check for leaks then refill by weight. How will you do that.

I gave or sold my basic equipment for car AC.
 
I think unless you seriously going to do (and trained) AC work as part of your day job it's better left to a Pro with the AC machine that can evacuate the system and save & filter the refrigerant.

The systems need to be filled by weight not pressure.

An electronic refrigerant sensor is needed and costs a few hundred $$.

So if the pressure is low and you think it needs a can of refrigerant you really need to evacuate the refrigerant, vacuum check for leaks then refill by weight. How will you do that.

I gave or sold my basic equipment for car AC.
Unfortunetly I generally don't have confidence in technicians working on most things, especially AC. I prefer to buy the tools, educate myself, and control my destiny when it comes to auto repair. Wish I had someone to hire to do the work, I simply don't.

BITOG has many top shelf professional technicians. But seems none of them want to move to New Mexico.
 
Unfortunetly I generally don't have confidence in technicians working on most things, especially AC. I prefer to buy the tools, educate myself, and control my destiny when it comes to auto repair. Wish I had someone to hire to do the work, I simply don't.

BITOG has many top shelf professional technicians. But seems none of them want to move to New Mexico.
How are you going to evacuate the AC system if that's needed? Saving the refrigerant?
 
Most home HVAC pros appear to use Yellowjacket analog gauges or Fieldpiece digital gauges. However, I have owned a Mastercool gauge set for ~18 years and it has been flawless. The only modification I made to the Mastercool set is to replace the original R-134a quick disconnect fittings with Robinair QD fittings which have the knobs that screw down to depress the Schrader Valves.

I highly recommend a Robinair vacuum pump as they are as good as they get.
Thanks for the recommendation on a pump brand. What would the minimum requirement be for a pump - in CFM or HP or microns? Assume my time is of no value :)

My thoughts are to get a cheap gauge set and a better vacuum pump. Is this a good or bad strategy? Is the absolute value of the high and low side that exacting really.

Do I need a micron gauge, or more succinctly - will it make my life significantly easier? Again, my thought is to buy the best pump I can afford and pull for a long time?

Any other hints you might have are appreciated?
 
Unfortunetly I generally don't have confidence in technicians working on most things, especially AC. I prefer to buy the tools, educate myself, and control my destiny when it comes to auto repair. Wish I had someone to hire to do the work, I simply don't.

BITOG has many top shelf professional technicians. But seems none of them want to move to New Mexico.
Well, we do try to get our groceries in Aztec 'cause no food tax and you can still get plastic bags down there ;) (a staple for dog poo)

FWIW I had also purchased a Mastercool can tap that was somehow problematic (I forget or have repressed the specifics!) and I could swear there was one other small Mastercool doo-dad that also annoyed me.

In the end I just knew to remember to choose Mastercool alternatives when available. I'm far from a professional a/c tech so YMMV
 
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Thanks for the recommendation on a pump brand. What would the minimum requirement be for a pump - in CFM or HP or microns? Assume my time is of no value
While I own a premium Robinair Cooltech 6 CFM, 2-stage vacuum pump, it is overkill for non-professional usage. You would be very happy with this Robinair VacuMaster 5 CFM, 2-stage pump for 1/3 the cost of my pump. I would not go lower than a 3 CFM pump with 2-stage capability. Changing the vacuum pump oil regularly, especially before long term storage, will ensure longevity of the pump by minimizing corrosion.
My thoughts are to get a cheap gauge set and a better vacuum pump. Is this a good or bad strategy? Is the absolute value of the high and low side that exacting really.
While you can get by with the $50 Pittsburgh gauge set from Harbor Freight, I would spend a bit more and buy the Mastercool set and add the Orion Motor Tech QD Couplers from Amazon. I started with the Pittsburgh gauges, but did not like the inaccuracy on the low end when drawing a vacuum. Most inexpensive gauge sets are satisfactorily accurate for low pressure side and high pressure side system readings, but falter when reading close to absolute vacuum (-29.92 in.Hg). Depending on what you currently own, you might also need to buy the refrigerant Dispensing Valve to accommodate the newer self-sealing R-134a cans.
Do I need a micron gauge, or more succinctly - will it make my life significantly easier? Again, my thought is to buy the best pump I can afford and pull for a long time?
I have never used a micron gauge and don't see the need for a non-professional mechanic, especially for automotive applications. Professional HVAC technicians use micron gauges because they are evacuating large volume A/C units for homes and businesses that require a long vacuum run time and precise measurements.
Any other hints you might have are appreciated?
This is just my preference, but I have found the gauge sets with 100% brass manifolds to be more durable than the cheaper units with the aluminum billet manifolds that have the sight glass window. Also, if you need to un-thread a gauge from the manifold, use pipe sealant paste, not Teflon tape when reinstalling.
 
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I have the cheap [amazon or harbor freight] equipment. Vacuum pump, manifold set and whatever. Only work on AC every few years of so. I can't see buying professional grade equipment if it's not going be used to make a living. What I have has worked well with occasional use for 10 or more years.
 
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I have the cheap [amazon or harbor freight] equipment. Vacuum pump, manifold set and whatever. Only work on AC every few years of so. I can't see buying professional grade equipment if it's not going be used to make a living. What I have has worked well with occasional use for 10 or more years.
I am that way most of the time - but from everything I am reading and hearing you need to have the right tools for the job in some cases. Not enough vacuum and you will end up with water in the system still. Inaccurate gauge set will cause diagnostic problems. A cheap setup is likely $200 and a decent one is $400. Seems like it might be worth it.
 
I am that way most of the time - but from everything I am reading and hearing you need to have the right tools for the job in some cases. Not enough vacuum and you will end up with water in the system still. Inaccurate gauge set will cause diagnostic problems. A cheap setup is likely $200 and a decent one is $400. Seems like it might be worth it.
I have the Harbor Freight vacuum. I like will invest in a replacement vacuum with increased capacity.
 
While I own a premium Robinair Cooltech 6 CFM, 2-stage vacuum pump, it is overkill for non-professional usage. You would be very happy with this Robinair VacuMaster 5 CFM, 2-stage pump for 1/3 the cost of my pump. I would not go lower than a 3 CFM pump with 2-stage capability. Changing the vacuum pump oil regularly, especially before long term storage, will ensure longevity of the pump by minimizing corrosion.

While you can get by with the $50 Pittsburgh gauge set from Harbor Freight, I would spend a bit more and buy the Mastercool set and add the Orion Motor Tech QD Couplers from Amazon. I started with the Pittsburgh gauges, but did not like the inaccuracy on the low end when drawing a vacuum. Most inexpensive gauge sets are satisfactorily accurate for low pressure side and high pressure side system readings, but falter when reading close to absolute vacuum (-29.92 in.Hg). Depending on what you currently own, you might also need to buy the refrigerant Dispensing Valve to accommodate the newer self-sealing R-134a cans.

I have never used a micron gauge and don't see the need for a non-professional mechanic, especially for automotive applications. Professional HVAC technicians use micron gauges because they are evacuating large volume A/C units for homes and businesses that require a long vacuum run time and precise measurements.

This is just my preference, but I have found the gauge sets with 100% brass manifolds to be more durable than the cheaper units with the aluminum billet manifolds that have the sight glass window. Also, if you need to un-thread a gauge from the manifold, use pipe sealant paste, not Teflon tape when reinstalling.
I ordered the gauge set, couplers and Dispensing valve you recommended. Still pondering which pump. Than you for the recommendations.

Now I need to find somewhere to buy nylogblue gasket sealant?
 
Unfortunetly I generally don't have confidence in technicians working on most things, especially AC. I prefer to buy the tools, educate myself, and control my destiny when it comes to auto repair. Wish I had someone to hire to do the work, I simply don't.

BITOG has many top shelf professional technicians. But seems none of them want to move to New Mexico.
This is what I did back in 2006 when I had a car that my fiancé wanted the air to work in but to have someone else to repair it was almost as much as the car was worth.
She told me she would buy me the tools if I learned how to do the work. I bought a couple of books and found an automotive AC forum with a lot of knowledgeable guys on it and some of them were actual AC techs.

I bought Robinair gauges. One set was for r134a and one for R12 since I still had a car that took it. I bought a Robinair 6cfm two stage vacuum pump which is overkill for automotive AC work, but it works great. I change the oil with Robinar vacuum pump oil after every use per the owner's manual and the pump still works like new after all of these years. I did have to replace the fittings for ones for automotive use which I bought from Robinair.
I initially used the small cans to charge with, but they were a pain to use to get the exact refrigerant amounts, so I bought a Mastercool refrigerant scale for the 30 lb tanks and bought a 30 lb tanks of r134. That was a game changer since it made recharging so much easier without having to disconnect the lines to switch cans and purge the lines of air. Someone later sold me an almost full 50 lb tank of R12 which I still have today with most of it still left. During that time, I also got my 609 certificate so that I could buy R12 from those who required it. This was when I was buying the cans and before I bought the 50 lb tank. I bought several 30 lb tanks of r134 some years back when they were still reasonably priced, so I have enough to last me quite some time.

The only thing that I don't have is a machine to reclaim refrigerant. For friends and family who want me to work on their AC systems and it needs to be empty, they have to go somewhere to have that part done. I also take my own vehicles somewhere to have it done if needed.

To date, I have successfully fixed around 25 vehicles with only one failure to fix.

Here is the AC forum that I learned a ton from.
https://www.autoacforum.com/
 
I read elsewhere that I should use it on all the hose connections on the manifold set?
I would not apply Nylog on the hose connections on the manifold set. The only leak I've ever encountered on a manifold was a gauge that was not fully tightened. I unthreaded it and resealed it with Teflon based pipe sealant paste.
Where else should I use it. Any o-ring I replace presumably. Anywhere else?
I would only use it on all of the o-rings, including the Schrader valve's o-ring & threads.
 
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