Nickel Tube Bundle for the following Heaters:
- Raypak ASME 399,000 BTU (406A) Digital Heaters
- The hydraulic conditions or water chemistry that caused the tube bundle to fail have very likely also damaged the bypass valve and Unitherm Governor. We recommend you replace the Unitherm Governor and inspect the bypass assembly. Failure to do so could cause premature failure of this replacement part.