Water Heater Replacement

GordonThree wrote:
The heat exchanger tubes, I wonder how well they work in reverse...? Thinking it could be used for hydronic under floor or baseboard heat.

NOT worth a hoot.
Tube is only 1/2" Diameter and makes very small surface contact with WH Tank wall...maybe 6"
HOT coolant from engine can warm the water in WH Tank up to 130*F during a long drive.....non flowing \

Switch for electric on that 'old' one (9E) would be on backside on water heater on junction box that covers the electric screw in element.

Using the 12V DC that feeds the old Propane ON/OFF switch is HOW the new switch should be wired.
Both electric and Propane ON/OFF switches use the same 12V DC Power source.

You will need to run a NEW DC wire from electric on/off switch to the 'WHITE OEM Wire' on NEW WH.

The OLD 120V AC Power form a circuit breaker is still used and connects to the DC Relay which then has AC wires that go to element....ALL on backside of water heater

All of this is explained in the conversion info in manual linked

The heat exchanger tubes, I wonder how well they work in reverse...? Thinking it could be used for hydronic under floor or baseboard heat.

Thanks OB. I had previously saved that PDF. I have the switch for the propane in my kitchen & I believe that the switch for the electric is by the water heater itself. I suppose I will just end up installing the new double switch in the water heater compartment & tap off the 12v line coming from the old propane switch (leaving it always on) to feed the new double switch. See any issues with that set-up?

Seeing as there is nothing to connect to that heat exchanger tube (motor coolant lines) you can just install and forget about that tube

AS for the needed conversion to the new model design see pgs 23,24 & 25 of service manual........Click for manual