Weighing Refrigerant In and Out
If you don’t use a scale every time you add or remove refrigerant I would suggest you begin doing so immediately if not sooner. Weighing in while adding is fairly obvious and is useful so you can keep track of what you are using and how much to charge a customer.
When you have a system that has just been repaired it is a good practice to weigh in the charge to factory specs plus or minus adjustments for lineset if it is a split system. This is all pretty evident, but why would you weigh a charge out? There are many reasons but I watched a video by Stephen Rardon today that re-ignited the importance of weighing refrigerant out in my mind. Whenever you have a failed compressor, weighing out the charge can help indicate whether possible undercharge or overcharge may have contributed to the failure. With any significant failure on an older system, weighing out the refrigerant can indicate whether a leak is likely. Stephen went so far as to weigh out the refrigerant on a failed shorted at the time of diagnosis… BRILLIANT!
Using refrigerant recovery as a means to find possible cause or even diagnose leaks on non-functional systems is next level diagnosis in my book. Use your scale.
Well done Stephen.
Bryan Orr is a lifelong learner, proud technician and advocate for the HVAC/R Trade