Belimo B207B Valve R-448A or the ignition sequence timing

or the ignition sequence timing out because the 24VAC signal is not completing the circuit to the gas valve

flat mounting surface

including the PD50

the high-altitude switch is still necessary to monitor venter pressure in thin-air environments

To convert to Natural Gas

Belimo B207B Valve R-448A or the ignition sequence timingThe Belimo B207B is a high performance 1 2" NPT 2 way characterized control valve engineered specifically for precise hydronic regulation in chilled or hot water systems. Featuring a 0. 3 Cv rating and an integrated characterizing disc, this valve ensures a linear heat transfer output through its equal percentage flow characteristic. The body is constructed from nickel plated forged brass, paired with a chrome plated brass ball and a nickel plated