HVAC test instruments help ensure that HVAC systems are correctly tuned and free of leaks that can affect system performance or damage components. Refrigerant leaks can cause HVAC systems to stop cooling and can pose a health risk to building occupants. Refrigerant measuring and monitoring HVAC tools help ensure systems are running at peak performance by taking a variety of measurements, including superheat, subcool, pipe temperature, and relative pressure. Dye injector kits include UV-fluorescent dyes that are injected into pressurized system to detect and locate leaks. UV leak detector kits include dye and other components necessary to detect leaks in pressurized systems, such as HVAC and hydraulic systems. Accessories include dye and other components to replace used kit components.