Mueller A17921 Manifold 320788-703 Ensure the porcelain is clean

Ensure the porcelain is clean of carbon deposits

this seat ensures precise proportional control of steam

0-5V) to match specific controller requirements

Always verify the 4 cell gasket configuration against your specific furnace model number before installation to ensure total pressure switch stability and combustion safety

Mueller A17921 Manifold 320788-703 Ensure the porcelain is cleanThe Mueller A17921 ReliefMaster is a heavy duty change over manifold engineered for high demand industrial and commercial refrigeration applications. This HVACR manifold features a 1 2" NPTFE (National Pipe Thread Fuel Extended) inlet and 1 2" NPTFI (National Pipe Thread Fuel Injection) outlets, providing a secure, leak proof transition for dual relief valve setups. With a design pressure (MAP) of 700 psig and a broad operating temperature range of