Well this has helped me make a decision.
I have toyed with getting a fitted diesel heated
system. But you can keep it.
I have tried the gas boiler ( always felt risky) and had the immersion heater fitted in my delivery tank ( professionally on a 16amp RCD job) in my last house.
For simplicity, safety, cost and a few other benefits
I will be rigging the immersion heater up again.
T