Mrs. Nott asked me to turn up the water heater. I tested at the kitchen faucet, and yes, 107 degrees F was too cool. I turned it up, and now it’s 133 F. Just how hot do you need for safe dishwashing? This is in a home, not a restaurant.
Thanks.
–Nott, staff galoot
The booklet that came with my new dishwasher said water temperature should be at least 140F. Mine has a water-heating cycle, but I ended up turning my water heater temp. up instead of always using that - we never had enough hot water anyway.
Now, if you have small children, pediatricians recommend that your water temperature be no higher than 120F. Damned if you do, damned if you don’t, I suppose.
Not a problem, if your dishwasher can boost the water temp up to 140. Set the water heater to 120 or less, and let the dishwasher do its bit.
In fact, keeping the water temp down is safer for everyone, not just kids. Have you ever turned a shower faucet in the wrong direction, and gotten a blast of “all hot?” If your hot water is over 120, you’d certainly remember having done so!
By the way, turning your water heater up won’t give you more hot water. A 40-gallon water heater can give you 40 gallons of hot water before it runs cold, whether the water is 120 degrees or 140.
>>>>>By the way, turning your water heater up won’t give you more hot water. A 40-gallon water heater can give you 40 gallons of hot water before it runs cold, whether the water is 120 degrees or 140.<<<<<
Just think about what you’re saying.
Um, if you mean it “won’t give you more” as strictly the volume of “hot” water in the tank, you’re right.
However, it’ll sure as hell give you more “warm” water when mixed with “cold” water from the other pipe. Simple physics, there is more energy in an equal volume of hotter water.
The practical side of this is: Since most of us take warm showers, you can get more and/or longer showers by upping the temp on your water heater (to a point).
To answer the original post, I’d say that water temperature that’s bearable to wash dishes in is probably marginally less effective than scalding water. Washing thoroughly, i.e., scouring, rinsing, and drying probably remove most germs even if you use cold water.
As long as you’re careful with known potential sources of harmful germs like raw meat, I’d say don’t worry about it. Nothing removes all bacteria (for very long, at least); They’re all around us, on us and in us at all times.
Granted, Stan Doubt. What I was getting at was that, if you’re constantly running out of hot water, pushing the temperature up a few degrees isn’t likely to cure the problem. Only a bigger tank will do the trick.
Laws vary from state to state, but in restaurants in Illinois, you either have to rinse in 180 degree water or soak in room temprature sanitizer for a minimum of two minutes.
In your home, 180 coming out of the tap would be too dangerous, particularly to the young and the elderly. I’m not aware of too many who sanitize dishes in the home (bleach in the proper concentration works).
Your best bet is to use a dishwasher with 140 degrees going in, as long as you have no little kids or elderly living in your home. If you wash by hand, use soap (doh) rinse well and let air dry. Never towel dry dishes.