Review on 🔧 Mastercool 66661 Brass Manifold Gauge Set - Enhance SEO by Terry Keown

I bought this last year for a project that was delayed so I didn't get a chance to use this sensor set. I recently bought an RV that needed to be repaired and the air conditioning refilled because it was completely drained. So this is the first time I have to use it. Although it appeared to work properly, it had a serious defect that I was unaware of until it caused me a great deal of grief as I tried to figure out what was going on. I was able to charge the AC system and it seemed to be working correctly, but none of the gauges made any sense. The top never reads more than about 50 psi. Long story short, I found that connecting the high side connector to the service port increased the pressure from the system but didn't read higher. Upon inspecting the high pressure port, I found that the center pin that pushes on the Schrader valve to open it was set too far back to open the valve. On the first push, the valve opens momentarily because you push a little further than when it snaps closed. I used my old service port to see if it would open on a fast connection. It doesn't open the valve at all when it snaps. You can open it easily if you push it all the way down, but this isn't the normal operating position. Comparing this short dial to the Harbor Freight set, I purchased a center pin that is twice the depth of the HF set. Poor quality control as many reviews say. To my regret I dismissed the negative reviews!