Hot tubs with a Spa Ozone Generator need a Spa Ozone Check Valve to protect it from water back-flow.  A Spa Ozone Check Valve is little part with a BIG job.  Protect your Spa Ozonator by replacing the Spa Ozone Check Valve annually!

The 7-4012 was replaced with a blue/black Ozone Supply Check Valve years ago, which was again replaced in 2008 with the green/white 7-1140-01 Ozone Check Valve (currently the most commonly used).

DEL Ozone 7-4012 Ozone Supply Check Valve Specifications: 

• Cracking pressure is low; there is no rating
• Single-barbed to fit 1/4" ozone tubing
• Polypro Housing with diaphragm
• If you have a Sundance Spa built between 2008-2011, two 7-4012 check valves may be a better choice for you than one 7-1140-01

If you have an old 7-4012 diaphragm Ozone Check Valve, note that they have no resistance (they basically don't protect your Spa Ozone Generator).  Some spas (like Sundance Spas) have low flow, and two 7-4012 Check Valves installed back-to-back works best.  But most spas can handle the improved 7-1140-01 Ozone Check Valve and we encourage the upgrade.  It's a good idea to keep a spare on hand.