Hydronic Installation... continued
By the time my new heater came in the post I had already done a lot of looking around the truck for a better spot to install it. The battery box was looking better and better. I sized it up and with carefull installation I could still get the heater plus a double battery system in the box.
Eberspacher Hydronic in Defender Battery Box
Battery box installations are recommended by Espar / Eberspacher but I wouldn't attempt it with the petrol version of the heater, for obvious reasons.
Mounting the Heater
The inner wall of the battery box was selected for mounting. The heater is supplied with a stainless steel mounting bracket. Locating the bracket was done with the heater installed on the bracket then marking the holes for drilling.
Coolant Connections
I used bulkhead fittings to cleanly route the coolant into the battery box. While I was at it, ball valves were installed to shut off coolant if needed (for heater removal). These valves were later zip-tied so that they were locked in the open position to prevent inadvertent closing. With the valves installed, I wouldn't have to deal with coolant leaking in the battery box when removing the heater. I considered a by-pass but opted against it for simplicity. I'll just connect the two barbed fittings with a length of coolant line if I need to use the truck without the heater installed. Finally, ninety degree elbow fittings finished the coolant connection through the battery box. All that was left to do was run the 5/8 inch coolant lines.