We have a customer who wants to convert all of his existing pneumatically controlled 3/4", 2-way steam valves in radiators to electronic for BAS control. The existing valves are mounted inside the radiators next to the elements. The pneumatic valve heads are obviously able to withstand the ambient heat generated from the steam (not sure of the ambient temperature) but we are afraid standard electronic valve actuators will fail in due time because most seem to be rated to withstand up to approx 125degF.

Does anyone know if any high temp electronic valve/actuator assemblies are available for this application or what possibly can be done to standard electronic actuators for heat protection ?