Hot water system

[spruce]

Oliver at Grippatank told me if you use 100% antifreeze in the header tank that it will increase the water temperature quite dramatically and it could damage the heat exchangers I can’t quite remember the full explanation but he said use a 50-50 antifreeze and water mix that’s what I have always done .

Never heard that one before.

The boiler temperatures are controlled and regulated by sensors in the boiler itself. If the boiler finishes it's heat cycle at 85 degrees, that top temperature is well within the specs of the heat exchanger, even when we put water pressure of 60 psi into the mix. I can't see why the concentration of anti freeze would change that.

In fact the motor industry sells anti freeze as a summer coolant as well.

So I'm confused tbh. I haven't seen anything in the Webasto workshop manual warning against a high concentration of anti freeze. Obviously we need the right anti freeze which won't damage the boiler internals. We use the orange coloured stuff that psa put in their vans.