4.5CFM Single-Stage Rotary Vane Vacuum Pump - 1/3HP, 150 Micron, 1/4" Flare & 1/2" Male Inlet - Ideal for HVAC Refrigerant Recovery, Auto AC Recharging, Wine Degassing, Medical Equipment & Food Processing (Model TA450)

I have a beat up 3cfm pump I got on a discount site for $25 years ago for doing some work on automotive systems (see the other pump in the photo). I'm attempting a mini split install and felt it was inadequate for the job but all the same put some fresh JB vacuum pump oil in it and after an hour still could just barely get it under 1000 microns. I kept the valve core in and I'm not using vacuum rated hoses but I'm not pulling through a manifold so I figured I'd give it a shot. I decided to purchase this cheap two stage pump figuring it was about the same price as a Robinair single stage 3cfm so I'd see how it went. I also got a second R410a dedicated YJ 41 series manifold but that hasn't come yet. I only do HVAC work 2-3 times a year so I don't need high end professional equipment but I want to find that prosumer price point of getting professional results as a budget price knowing it can't take hard abuse but will last me decades of limited use. I gave this a shot with the same setup as you see in the picture I used with my cheap pump. I managed to get below 300 microns in under 5 minutes and below 200 within 30 which was perfectly fine for my needs as this was a second evac and the system was filled with argon when I started. This is a good value, great price point, I will update if I have issues down the line but right out of the box it's doing everything I'd hoped and very well.As a side note, if you're doing a mini split install and you want it done right, get a flare tool and deburring tool to redo those bad factory flares, get a leak detector, get a micron gauge, get a good vacuum pump, get a valve core removal tool and so on. You really can't get a $100 combo setup and hope to have good results. You're going to have to spend at least $300 on equipment to properly DIY a split. Also, ideally you have welding gear and an argon bottle or the ability to do a nitrogen (or argon as mentioned though that's a waste of money) pressure test first. Flare fittings are tricky and having these abilities saved me from releasing the refrigerant into a system it would have leaked out of within the first 6 months.