Thermostatic mixing valve and dishwasher

swagman

I have a dishwasher which can be connected to hot or to cold fill - max temperature of water must not exceed 60 degrees.

I have solar panels and am keen to use this as a water source for the dishwasher. Any snags if I fit an adjustable thermostatic mixing valve inline in the water supply to the dishwasher?

andrew-b

Are the solar panels already being used to supplement the heating of the hot water supply in the house. If so surely there is some sort of safeguard to prevent scalding hot water coming out your taps already? Could you just link up with the hot water if it's controlled to 60C (about the recommended level for the thermostat on a hot water cylinder anyway)? Thermostatic mixing valves arent the cheapest of valves around.

Andy

plumb1_2

It doesn't have to be thermostatic, a blending valve would be ok to use with the dishwasher.

swagman

andrew-b wrote: »

Could you just link up with the hot water if it's controlled to 60C (about the recommended level for the thermostat on a hot water cylinder anyway)? Thermostatic mixing valves arent the cheapest of valves around.
Andy

Yes, the tank stat, fed by the panels, is set to 65C, but it could be set to 60C, so maybe it really is that straightforward!

shandypants5

There are other issues you should consider first before feeding your dishwash or any appiliance hot water.

Most appliances only draw a small amount of water before they stop and begin the cycle.

So what actually happens is, they draw cold water from the pipes.

Then, just as the water is getting warm, they shut it off and heat it themselves to the required temp, ie just as if it was a cold fill.

So, all you have done is fill the pipes in the walls with hot water, and this will just heat the walls and waste energy, waiting for the next "call" from the dishwash.

It is actually cheaper to just connect your appliance to the cold fill and let it heat its own water.


How you would use your solar water to best affect I am not sure, but the standard hot fill should be avoided.

plumb1_2

swagman wrote: »

Yes, the tank stat, fed by the panels, is set to 65C, but it could be set to 60C, so maybe it really is that straightforward!

60c= possible Legionella

swagman

Thanks for these various comments. It looks like it isn't worth doing, especially as there is quite a long hot water pipe run from tank to dishwasher. Cheers