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.

Replacing Legacy Bosch Tankless Heaters

We have just started getting some calls from customers who are looking to replace some of the original Commercial Bosch Tankless Water Heaters that were introduced into the market 20 years ago.

If you are looking to replace any of the following Bosch On-Demand Water Heaters, please give us a call at 888.726.9752 so we can help you match your heater up with its current replacement model:

• Bosch WR400-1K (117,000 BTU, Pilot Light)
• Bosch WR400-3K (B) (117,000 BTU, Electronic Ignition)
• Bosch WR400-5K (117,000 BTU, Pilot Light)
• Bosch WR400-7K (117,000 BTU, Hydro Ignition)
• Bosch WR430-3KV (125,000 BTU, Electronic Ignition)
• Bosch WR125-K (125,000 BTU, Pilot Light)

Steve