Heater and water pump

I am going to use a heater element from a household boiler to create heat in the car since there will be no gas engine to produce heat.

The heater

I found a heater at Rinkaby Rör which delivers 4,5kW of Power at 230 VAC. It has three heater coils, each with a resistance of 37 ohms. So, when I connect that to 220 VDC it should produce three times 1300W = 3900W of heat. I hope that will be enough for the cold winter days when temperature drops to -25C.
The heater will be placed in a steel tube with fittings to connect it to a water pump and the ACC that heats the passenger compartment. The heater will only be turned on when the ACC heat flap is open and then, on-off control will be performed with a solid state relay based on a the output of a thermo sensor.
The water pump is an Electric Booster pump from Davies Craig that will continously pump 15 l/min at temperatures ranging from -40 to 120C.
Whatch the video when I tested the pump today.