No but … While many installers try to use these valves on their systems because; a) the are cheap, b) they are readily available, and c) they frequently come with your tanks (meaning you probably have one lying around), using them on your collector loop will cause problems. A standard hot water heater T&P valve (the most common type) is set for 150 psi and 210 degrees Fahrenheit. If you use one of these in your system the high collector temperatures will cause it to periodically release collector fluid on both drainback and glycol systems. Released fluid means service calls to recharge the system, which we want to avoid. Some installers advocate cutting the temperature probe off flush with the casting to eliminate the temperature sensing portion of the valve. While this will eliminate the temperature portion of the relief valve, you will break the protective seal on the thermocouple. This will then start to oxidize and cause the valve to fail prematurely. This premature failure can take a year or 20 years. Avoid the warranty call-back and spend the few extra dollars to install the right pressure relief valve (Part #: P-V-3PR76).
