Astoria Curved Heat Exchanger resources/chemex-infographic this is the curved "newer"

this is the curved "newer" version

but shut off and depressurize the boiler before removing the old gauge

digital PID controller

and machine diagnostics

Astoria Curved Heat Exchanger resources/chemex-infographic this is the curved "newer"42 mm diameter curved heat exchanger for Astoria and compatible models. Fast shipping when in stock. When out of stock this becomes a special order item and typically requires 2 4 weeks for processing prior to shipping. Specifications: Diameter: 42 mm Astoria OEM part #: AS_159 Compatibility: Astoria models requiring curved heat exchanger Installation: Direct replacement in boiler circuit Recommended for qualified technician.