I have hot air but no hot water in my dishwasher

I once bumped the water supply shut-off under the sink and turned the supply off at the shutoff. Other than that, have you had any work done on the hot water tank recently ?

We had this a while back - it was something to do with a blocked filter right inside, which meant the hot wasn't coming on. The repair man had to put in a new filter, which had been blocked possibly cos we had been doing quick washes with environmentally friendly detergent, and that solved the problem.

Hi -
I can't see how any installation problem would cause this - if the dishes are still wet at the end of the cycle, you'll probably find the water isn't heating during the wash cycle. The dishwasher uses steam to heat the washing compartment and dry the dishes. It would appear that the dishwasher isn't heating water internally.
Even if the washer was accidentally connected to the cold water supply ** (see note), this shouldn't happen as regardless of the water supply temperature, the washer should still heat the water to the correct temperature internally.
** UK dishwashers should be connected to the cold water supply. For US installations, dishwashers are commonly connected to the hot water supply. For other locations, please consult your installation instructions.
I suggest you start a regular wash cycle and leave it to run for 10-15 minutes. Then open the door and test the temperature of the water in the base of the washer by hand. The water should be hot and there should be steam present in the washer when you open the door.
If the water is cold or only warm, the water isn't being heated internally or isn't heating to the correct temperature, in which case you should contact the retailer or Bosch Service immediately for a replacement. Do not accept an offer of repair on a brand new washer!
Additionally, do not attempt to repair the dishwasher yourself when under warrantly as this will invalidate the warranty.
Hope this helps. If you need further assistance, please let me know your location and the model number of the washer. This should be laser-etched into the top of the door if you can't find it on any of your paperwork.
Regards, BElectric

Hi and welcome to FixYa, I am Kelly.

What is happening is that your cold water flow is greater in volume (gals per min) than your hot water. So when you open the cold water it is mixing with the hot water inside the faucett or shower plumbing and actually reverse flowing back into the hot water heater plumbing. The reverse flow slows the water flow sensing turbine inside the heater and it is thinking that there is not any water flow. (There isn't actually due to the equalization of water pressure when you open the cold water faucett) Since this is a safety feature of the tankless heater to keep it from overheating, it shuts off.
Somewhere in the hot water plumbing there is a major restriction. It may very well be the internal plumbing of the tankless hot water heater or the flow detector design.

There are 2 ways to correct this. The easy way would be to restrict the available cold water flow. You can do this by installing another shut off valve inline with the cold water plumbing and just not open the valve all the way. You would have to adjust the setting so that the hot and cold water can be on at the same time and the hot water heater stays on. The hard way is to locate the hot water flow restriction and eliminate it.
It is possible.... if you have a flow restrictor in a shower head or a screen in a faucett areator that they are partially clogged. Clean any flow restrictors and screens then see how the hot water heater performs before you start modifying plumbing.

Thanks for choosing FixYa,
Kelly

My friend, that siemans is a night mare to open. Just done one recently. Anyway, looking at it simply, i would suggest you check the inlet water filter. if water is slow to come in it will cause this problem. Remoe the water pipe from the solonoid and look for sieve. clean it well retry.

I had the same issue s when I drained my hot water heater. I poured a few quarts of water in the bottom of the washer, and started it. Worked like a champ ever since.

no it should be plumbed into the hot side... it will not wash untill the water is hot enough ...

Dishwashers normally are hot or cold feed.
My wife runs water at the sink to get it hot going in before turning on the dishwasher.
You can use either cold or hot water.
We have ours hooked up to the hot water side.
They work better hooked up to the hot water.

What are you draining into - an air gap to a disposal, air gap to drain, directly to disposal, or directly to drain? How long has this been happening, and have you done any plumbing work recently (new disposal?)

Greg

the dishwasher will probably heat the water the rest of the way for you. depending on the specs and features.
hot water is not likely an issue with the dishwasher itself.
you could have cold water plumbed to the unit by mistake.
also, it could be that it is not fully pumping out, and the water going in is mixing with water in the sump.
try running it for few minutes and then pump it out. start a new cycle and see if you are getting hot water. if not, then at try to confirm that the unit is heating the water on its own. run it for about half a cycle and check the water temp again.
you do need hot water to clean in most units.
for certain this is a plumbing problem that is delivering cold water. and if its not heating, make sure that it should be per manufacturers specs, and call for repairs if its not heating the water.
good luck
mark