Hydrotherm 59-1089 Air Filter R-448A Verify your model number (such

Verify your model number (such as RDF or ADF) and check for the 1/2" NPT pipe size to ensure a proper match

Broad Cross-Reference: Direct drop-in for S1-024-35327-001 through 005

and M9220 families

This snap-acting changeover ensures the environmental control system maintains precise setpoints without the gradual drift common in lower-tier controllers

The unit includes an IP44 rated enclosure when mounted on a flat surface

Hydrotherm 59-1089 Air Filter R-448A Verify your model number (suchThe Hydrotherm 59 1089 Combustion Air Filter is a critical OEM filtration component engineered to maintain the stoichiometric balance and internal cleanliness of high efficiency condensation and hydronic heating systems. Specifically designed as a direct replacement for Hydrotherm boilers, this combustion air filter intercepts airborne particulates, dust, and environmental debris before they can reach the burner assembly. By providing a consistent