GlobalTownecarries most parts for the Bosch gas and electric tankless water heaters. This information is to confirm the difference between the older flow switch and the newer flow switch for Bosch Powerstream and Powerstream Pro units. The older flow switch part number 8-738-701-694-0 would be for any Powerstream and powerstream Pro models with a serial number beginning with "31" or less. The newer flow switch part number 8-738-700-865-0 is for the newer Powerstream and Powerstar units with a serial number of "32" or higher.
The old style is 87387016940
(serial number 31 and below)
The new style is 87387008650
(serial number 32 and higher)
For further questions or to order parts please call GlobalTowne at 888-726-9752.