Whats the issue with installing schrader back in while under vac before charging , risk of air getting in from small gap in core removal tool or running the risk of it pulling in schrader and letting air in ? Great video just hung up on this point
Not a tech here, but have now done much research. I think the issue is that you have pulled a deep vacuum on the system, and if you expose the system to any air, it will definitely get sucked into the system thereby ruining the whole process. So, he has you purge the air as best you can with vapor from the tank before tightening the tank connector, and then let vapor in the tank fill the vacuum. You then re-install the core in a vapor atmosphere without any air.
Thanks clarified the difference between core removal tool, core depressor tool and just a tee, and how to use the depressor in combination with the removal tool. Good Stuff!
I do not impress easily, BUT you Sir did a phenomenal job. I am not an HVAC tech, though I did see the original AC unit designed by Dr. Gorrie for medical use, but we in Florida are thankful. I just bought a core removal (Mastercool) system to use on my wife's SUV. I saw your video title, and thought there is never too much information, I watched, and was not disappointed. Best wishes, and many thanks!
All i hear from the experts is never do anything to allow even the tiniest bit of air in any system or it will damage something in the system.. but yet ive had to get trained by guys whove been in the field for 30 years and watch them screw into a frozen unit without wiping anything off or purging. Dirt and all ive seen on the service port and they just screw in their old gauges that been under the seat and an old tank. Then they go to charge it and set the tank upside down on the fan and proceed to fully open all valves and watch their gauges, eventually cut it all off and when they disconnect they always let a plume out thats big enough to be a ninja smoke screen , then they shake their hand that took the freeze shot, rub it on their pants, and most of the time never put the caps back on the service ports and toss the gauges in their bag and go. Me witnessing this and seeing these systems still running years and years later.. hell i watched one guy only replace the coil and blower unit indoors with a r134 newer unit, leave the old r22 condenser and compressor, but just turn it upside down trying to drain what little oil falls out, pull a vacuum on it, fill it with 134 and charge em 7 grand.. but low and behold that crap show is still running 3 years later.. the outdoor unit was over 20 years old.. lol.. and i touch a unit not even hook into it and instantly clog the metering device or filter.. im just saying here ive seen some magical shit just work for these older cats.. crazyness..
same boat with ya, I work with a 60 years old guy. exactly as what you've described. doesn't even use a micron gauge. but all units we touch, is still working till to this date.
Just went through this on a novice level with the A/C on my truck. The low side service port was faulty. The Schrader would not depress but the system was already compromised so it wasn’t vital we apply positive pressure to install the new valve. Ordered the new high side port an began the whole process. A/C works better than ever now.
Another great informative video,as usual Brian!! I can't let any body touch the C.R.T. YOU'D think it really is self explanatory, many years ago ,90's not sure first time I saw one . Co-worker of mine put it in my hand and said nothing about how it works ,told me figure it out give it back in a day or 2. Invaluable tool!HOPEFULLY more people will get one nd understand it's true potential. You my friend are a big help at making that seem possible. I don't let anyone ,use mine. Until they prove to me it's multiple fuction's. Great video!!!!
What brand of schrader removal tool , you are using for vacuum? I used yellow jacket but when I close the valve the vacuum pressure rise very high and quick
How high is very high? Most ball-valve type fittings like these tools will trap a pocket of air between the valve and the valve body. When you close a valve near a micron gauge, you'll typically see it rise 200-400 microns. Leaving the valves just short of fully open near the end of your vacuum process can help suck that air pocket out of them.
How do you Handle when the ports have only a couple of inches clearance before the cabinet gets in the way of the core removal tool and you can’t use them . How would you r&r the cores?
I find it easiest to break vacuum with low pressure making it much easier to reinstall core. Also I have made it a habit of pulling low side with unit running and pulling highside with unit off whenever possible.
The shradder core on my system appear to have slightly longer stem, not allowing me to reach with shradder removal tool once threaded on. Can’t seem to hear or feel a click, signaling that the removal tool has grabbed on to the core itself. Thoughts?
Your the best youtube teacher by far love your video's. That orifice you have used in the past for precision charging, where did you get it and whats the tech name for it. Much appreciated
Hi Bryan, Just for my clarification, before installing the schrader cores at the completion of the evacuation process, you recommended putting a positive charge of vapor into the system. Is it OK to use a small amount of vapor from blended refrigerants such as the R 400’s? My understanding is to always charge from the liquid state when using blended refrigerants. Also, Is a positive charge 5# acceptable or do you recommend a different psig level to bring the system above atmospheric pressure? Thank you very much, I really enjoy the excellent content that you and your team provides!
It's fine to use a bit of liquid as long as you're only taking it to about 10psi. At that pressure 410 boils at below -20 so unless you're in the poles you shouldn't have any liquid left as long as you don't race to crank up the compressor.
Thank you for explaining this. I've been recovering and vacing through my manifold and obviously at times it's beendifficult and often taking way to long 😪 I've seen this free flow method before but never really understood it until watching this video. I switched from being a gas heating plumbing engineer 5 years ago to work on ASHP'S and other renewable heating systems. I was sent on a City & Guilds Level 2 Award in F Gas and ODS regulations which basically covers refrigerant handling. By no means does this make me a refrigerant engineer but I endeavour to fill in the gaps and hopefully gain a much better understanding. Once again thank you for this explanation.
Just wanted to clear up some confusion 2:25 Are you saying that having a core removal tool is inefficient for vacuum and recovery or only if you are leaving the core in with the core removal tool attached to the port just so that its making connection. And then trying to pull vacuum or recover refrigerant out of the system is inefficient? - Also, in another video there was discussion of when to use a core removal tool. It was mentioned that it may not be a faster process when adding a small amount of refrigerant or in other applications. Would you ever consider using this tool in quick jobs with little or minimal refrigerant being added? For install, adding positive pressure just means unlocking the refrigerant from the condenser before you put the core back in? - How often does the O-ring need to be replaced and is there a quick way of checking for leaks with Nitrogen pressure without installing the core removal to the system?
Do you do it that way, I’m about to start pulling my vacuums without the manifold but I’m guessing it’s too much pressure, your way makes more sense but that’s all I can think out
How far should the schraders be screwed back on? So that later you can get readings with a gauge. I have had incidents where after putting back the schraders , I do t get a reading
So when I'm done with the vacuum I close the valve on the core removing tool unscrew the hose connect my charging hose and let freon in the lines then install my core thing to the service port then open the king valves right?
so when you have the crt's hooked up to the valves like after you did a nitrogen test and you take out the cores is it Normal to feel that air pressure push the knob out on the crt?? like when you have to push in to take the cores out of the valves on the condenser it allows some air pressure to build into the crt I have the navac crt's and one appion crt. I used them recently for the first time w a navac vacuum pump that has the built in micron gauge
so say it's a new system new lineset and condenser do you open the valve on the condenser and then shut it before inserting the shrader back in so there is more pressure prior to inserting the shrader
Thanks for sharing...so the final step (after the system is charged and under positive pressure) when inserting the core BACK into the system, won't a small amount of air from the rear chamber part of the CRT will be introduced into system? Is this a negligible amount and not to be worried about?
I used a defectove adapter for my mini split during the vacuum process which wasn't vacuuming the lines because the Schrader valve wasn't being depressed and then I stupidly released the refrigerant into the system. If i recover the reidgerant and vacuum them will that work, or should i remove the refrigerant and add more.
I have a feeling there's going to be some refrigerant figured in with that amount of money. No it's not something you want to do yourself. Do you have the tools and the knowledge? I'm assuming you don't just by you asking that question. Call a qualified tech. You're going to get yourself into a jam and cost yourself more money.
Schrader Valve and Core Removal tool cost less than $50. However, knowledge of how to DIY is priceless !.... Yes you can do it...look for several tutorials...
I personally just crack my tank to let some liquid into my manifold, purge air out of my hoses, close the tank and purge while connecting my hoses to the core removal tool and let whatever I have in my manifold into the system, depending what size the system is you might have to let more liquid out of the tank but I try to just get it to like 10-20 psi and then put the scraeder core back in and move forward with charging once all cores are in.
I've given up tryna isolated my micron gauge since I find ball valves almost always leak under vacuum which is a real shame innit . Very good vid , Bryan you're on a roll lately mate keep it up blud . Next if you could show how to maintain/ rebuild VCRTs that'd be brilliant. Cheers mate !
I always use core depressors to attach my micron guage and never have to disconnect it before releasing refrigerant after a vacuum. They are pretty cheap and an awesome tool to have.
