Setting a Lower Water Temp

[JojoM]

I was reading a few articles and one mentioned that with a tankless you can set your water temp lower than a standard tank, say 115 degrees. The other article I saw mentioned turning down the water temp to increase the hot water flow if you're getting warm water. I guess if the water temp is lower then, you're turning up the hot knob/handle more to increase water flow. Not sure what the effect would be on the dishwasher or washing machine keeping the temp around 115.

Any of this make sense?
Thanks

 

[Bannerman]

Dishwasher detergent will typically work best at 140F or higher. Even with a water softener, I find unacceptable cleaning results when the water temperature supplying our dishwasher is lower. Some will utilize the dishwasher's electric heating element to boost the water temp, but that will extend the run time and use higher priced electricity vs less costly natural gas.

Most laundry detergents are now formulated for cold water so temperature will not be as critical as it had been previously.

For a warm wash with lower temperature inflow, many will use the clothes washer's full Hot setting instead of Warm as they may have previously while the water temperature was higher.

Lower temperature from the WH, will result in a larger portion of Hot water being used to obtain your usual preferred temperature while bathing.

A benefit of a tankless that is equipped with a remote controller located within the living space, the water temperature may be easily altered to suit the specific application the water will be used for instead of selecting one temperature for 40-60 gallons sitting in storage within a tank type water heater.

 

[Sponsor]

 

[Dana]

I was reading a few articles and one mentioned that with a tankless you can set your water temp lower than a standard tank, say 115 degrees. The other article I saw mentioned turning down the water temp to increase the hot water flow if you're getting warm water. I guess if the water temp is lower then, you're turning up the hot knob/handle more to increase water flow. Not sure what the effect would be on the dishwasher or washing machine keeping the temp around 115.

Any of this make sense?
Thanks

With a tankless the effect the lower temp setting on dishwasher or front loading clothes washer performance is almost NOTHING!

Tankless water heaters have a necessary ignition delay (for purging the flue of potentially explosive mixtures) before firing, and most newer appliances fill very low volumes in even lower volume bursts. Some fill bursts are so short that some tankless units won't fire at all, or never stabilize in temperature, and the majority of the water going to the appliance is the cold water that passed though before it fired up.

A number of water sipping dish & clothes washers have auxiliary electric heaters to bring the water up to some pre-determined (not usually user settable) minimum temperature to get around these issues. Some dishwashers don't even draw enough water to fully purge the distribution plumbing between the water heater (any type) and the dishwasher if they are on opposite sides of the house. Some water-sipping dishwashers only use ~2 gallons per cycle. Fifty feet of 3/4" copper has about 1.25 gallons of water in it, so there's no WAY it would be getting 140F water from a water heater 50' away, even if it were a tank rather than a tankless. Most of the water would be at whatever tepid temp the distribution plumbing had settled to between draws.

 

[wwhitney]

Which is why with a tankless I always hand wash some pots with the water on full hot, then start the dishwasher once the kitchen hot supply line has been fully primed with hot water. But I would do the same with a tank type heater.

Cheers, Wayne