Bosch AquaStar 2700ES / 2400ES Heat Exchanger

The Bosch AquaStar 2700ES / 2400ES Heat Exchanger Part 8705406422 is the replacement heat exchanger for all Bosch AquaStar 2700ES and 2400ES tankless water heaters.

This part is also the replacement Heat Exchanger for the Bosch Therm 940ES, 940ESO, 830ES and the Bosch Evolution 500.

Bosch AquaStar 2400E / 2400EO / 250SX / 250SXO Heat Exchanger

The Bosch AquaStar 2400E / 2400EO / 250SX / 250SXO Heat Exchanger Part 8705406285 is the replacement heat exchanger for all Bosch AquaStar 2400E, 2400EO, 250SX and 250SXO tankless water heaters.

This part is also the replacement Heat Exchanger for the Bosch ProTankless 635ES and 635ESO tankless water heaters.

Bosch Aquastar 125BS/1600PS Heat Exchanger

The Bosch Aquastar 125BS Solar Heat Exchanger Part number 8705406189 is the replacement heat exchanger for the Bosch Aquastar 125BS tankless water heater. It is also the replacement heat exchanger for the Bosch Aquastar 1600PS tankless water heater.

The Bosch Aquastar 125BS/1600PS Heat Exchanger will NOT work for the Bosch Aquastar 125 series, 425PN, 425HN and 425HNO tankless water heaters. Please click the link for a Bosch Aquastar 125 series heat exchanger part number 8705406380.

Bosch AquaStar 1600 Heat Exchanger

The Bosch Aquastar 1600 Heat Exchanger Part 8705406386 (87054063860, 8-705-406-386-0) is the replacement heat exchanger for all Bosch Aquastar 1600P and 1600H tankless water heaters. It is also the replacement heat exchanger for the Bosch Therm 520PN and 520HN tankless water heaters and for all Bosch ProTankless 425PN and for certain Bosch ProTankless 425HN (with serial numbers starting 686 and higher) tankless water heaters.

The Bosch Aquastar 1600 Heat Exchanger will NOT work for the Bosch Aquastar 125B, 125BO, 125BL, 125X, 125HX, 125FX and the following Bosch ProTankless water heaters: 425EF, 425HN (with serial numbers starting 685 and lower) and 425HNO. Please click the link for the Bosch AquaStar 125 series heat exchanger part number 8705406380 (87054063800, 8-705-406-380-0).

Please call us at 888-726-9752 with questions or to place your order.

Bosch Aquastar 125 & WR400 Series Heat Exchanger

The Bosch Aquastar 125 Series Heat Exchanger Part #8705406380 (old part number 8705406235) is the replacement heat exchanger for all Bosch Aquastar 125 series and WR400 series Bosch tankless water heaters (regardless of Serial Number).  Astravan is a company in Canada that use to distribute the older Bosch WR400 series tankless water heaters.

Heat Exchanger Part #8705406380 (87054063800, 8-705-406-380-0) is the direct replacement for the following Bosch tankless water heaters:

125B, 125BO, 125BL, 125X, 125HX, 125FX and the following Bosch ProTankless water heaters: 425EF, 425HN (with serial numbers starting 685 and lower) and 425HNO, WR400-1KV1P23S3100, W400KD5  P23S3100T2, WR400-3K V1B23S3100, WR400-7K  V1G23S3195, WR430-3K  VM1E23S3190, WR430-3K  VM1E23S3195

The Bosch Heat Exchanger Part #8705406380 is NOT compatible with the following models:

125BS, 1600P, 1600H, 425PN, certain Bosch ProTankless 425HN (with serial numbers starting 686 and higher), 520PN, 520HN, WRS400K 1P23S3100T2.

Please call us at 888.726.9752 with questions or to place your order.