Dishwasher Water Supply - Hot or Cold?

[tavish]

Just got new dishwasher (Bosch Exxcel) and instructions say can be plumbed to either hot or cold. Bosch recommend cold but do not state why.

To me it would seem more efficent to allow my boiler to heat the water than the dishwasher, and therefore connect it to the hot. However, from reading around it appears that wash performance may be reduced if connected to hot as there is less soaking time (as the water does not need to be heated). Also any cycles the dishwasher would just use cold for would now be using (expensive) hot water.

I know, I know, I should suck it and see - which I will - but just thought someone may have some valuable thoughts / experience of the pros and cons.

 

[ZenStalinist]

It might be more cost effective to allow your boiler to do a lot of the heating but not more efficient.

On another note, plumbing it to cold would allow your dishwasher to take much more precise control over the water temperature, and hence it is usually reccomended. For example, what if you have it in low temperature mode, and the water from the boiler eventually arrives at more than 45c (usually the temperature for low heat dishwashes)?
I would think it for this reason.