Wednesday, April 6, 2016

Periodic Maintenance for Bosch 1600P/520PN & 1600H/520HN

The Bosch gas tankless water heater model numbers 1600P and 1600H should have annual and periodic maintenance done to prolong the life of the heater.  Bosch Thermotechnology is no longer making the retail models 1600P and 1600H but the new models that replaced them are the Bosch 520PN and the Bosch 520HN.  GlobalTowne carries parts for the Bosch 1600P/520PN and the Bosch 1600H/520HN.

As per the installation manual, the heaters should be checked annually for any debris in the venting, cleaning of the inlet filter screen and cleaning of the water valve.  The water valve should be cleaned with white vinegar and then the pushrod inside the water valve should be lubricated with plumbers grease or silicon grease.  The Bosch tankless water heaters should have a water valve rebuild done every 3 - 5 years depending on the quality of the water where the heater is installed.  The water valve rebuild kit (WVKITCT) #7738001923 includes the metal retaining plate, 2 set screws, pushrod and a packet of lubricant.  Call GlobalTowne at 888-726-9752 to order the water valve kit and other parts.

Below is a diagram of the water valve.  Service bulletins can be downloaded off the Bosch website at