What are the check valves used in HVAC systems

The No. 375 check valve is made of a one-piece cast brass body. Designed to operate in any position, a sensitive spring has been added to close the poppet ... Its short linear stroke and spring return action combine to close the valve prior to flow reversal which effectively eliminates the shock and water hammer ... The compact and lightweight valves are ideal for all class 3 contamination risks as per Water Supply (Water Fittings) Regulations 1999. Double check valves ... 233AB LF Brass In-line Check Valve. FPMSoft Seat. Low Lead BrassDisc Spring Loaded (SS304 spring). Horizontal or Vertical. Low Noise Operation. Product Overview: Size: 2" to 24". Pressure rating: Class 150. Material: Carbon Steel. Please refer to Datasheet for full technical information. Parker's check valves are available in various sizes, pressure ratings, flow capacities, and crack pressures to meet the requirements of most hydraulic system ... A Sump & Sewage Check Valve is very easy to install, and even though they are not usually code, it is good practice to make sure you have one included in your ... Seat N/A Buna-N (75 dur.) CAD Icon (for items table), N/A. 312H1A4C3, QUOTE, 0, Size N/A 2 ... Proco Products is a leading manufacturer of rubber check valves, these are fully passive devices requiring neither maintenance nor any source of outside power ... DeZURIK offers many types of check valves to handle different applications and decades of experience in proper application.