I encountered a couple today & just thought I would share with those who may not have experienced them yet.
The bottom ¾ is much like any other unit with 2 heating elements while the top ¼ is a mini heat pump. This heat pump has an air filter on top, an exhaust on the side & a condensate line (white pvc) that drains outside.
The cold water comes into the room, up the wall to an anti-siphon device (required by our local AHJ) then back down to the bottom of the unit where it enters next to the drain port. The water is heated by the 2 elements, kept hot by the heat pump & then exits from the middle of the tank.
The TPR valve is located on the side & plumbed to the outside with cpvc (off white pipe)
Takeaways for inspecting:
Inspect much like any other electric water heater
-elecrical disconnects per usual
-shutoff valve on cold water per usual
-TPR valve & plumbing per usual
-expansion tank required per the usual (missing on these units)
-the higher discharge line is a condensate line, no need for special piping material
-the cold water feeds in from the bottom
This looks crazy but isn’t really all that different. As far as the condenser, I check that it runs, (usually comes on when I discharge the TPR valve) has filter, air intake & exhaust has proper clearance, condensate drain plumbed correctly.