Water Heater Question....increments on temperature dial

[DaTT]

I have a Rheem RP180 hot water tank.....I would like to turn up the temp on it. The temp is currently at 125 which is the painted mark on the temperature dial, also the temp that the tank comes set at from the factory. Anyways, anybody know what increments the hash marks are set at on the dial?

Thanks

 

[Rubycon]

I would not trust them with a ten foot pole!
The clicks are for reference ONLY.
ALWAYS measure the temp and then adjust up or down.
125F is an economy setting. 140F is probably the highest you should go and wastes more energy - wrap the tank in blankets if possible. Also higher temperatures increase the risk of scalding so be careful! I would NOT raise the setting without taking the temp at the tap first.

 

[biggestmuff]

Turn it up until the water is more comfortable. Seems pretty obvious.

 

[Red Squirrel]

Turn it up until the water is more comfortable. Seems pretty obvious.

That's what I did with mine. It has dots, then A B C and "Very Hot" so mine is set to B. I had it set to C and it was ok, but decided to lower it when I fixed the temp limiter in my shower. I like very hot showers since I'm so cold when I wake up early in the morning and have to get out of bed.

 

[DaTT]

I would not trust them with a ten foot pole!
The clicks are for reference ONLY.
ALWAYS measure the temp and then adjust up or down.
125F is an economy setting. 140F is probably the highest you should go and wastes more energy - wrap the tank in blankets if possible. Also higher temperatures increase the risk of scalding so be careful! I would NOT raise the setting without taking the temp at the tap first.

I don't expect them to be exact, just used as a guideline. I want to get it up to 140F to see if it will improve my dishwasher's dish washing capabilities as per the recommendation of the repair guy that was here earlier.

The temp at the tap was 125F before I raised it 2 notches. Will check soon to see the new temp.

 

[DaTT]

Turn it up until the water is more comfortable. Seems pretty obvious.

Your post does not have anything to do with my OP.

 

[DaTT]

Appears to be ~10 degree increments.

 

[MikeyIs4Dcats]

10 degrees

 

[iGas]

Depends on the local jurisdiction the minimum HWT can be 120F or 125K and max of 140F (factory default setting is 140F). Plumbing codes requires that the HWT temperature to be set at 140F.

Personally I wouldn't touch the dial, and leave it at factory default or crank it up to 140F to prevent bacteria/legionella growth.

Legionella acquired its name after a July, 1976 outbreak of a then-unknown "mystery disease" sickened 221 persons, causing 34 deaths.

In the United States, the disease affects between 8,000 to 18,000 individuals a year.

At 60 °C (140 °F) - Legionella dies instantly - pasteurisation occurs.

Add:

Legionellosis is an infectious disease caused by Gram negative, aerobic bacteria belonging to the genus Legionella.[1][2] Over 90% of legionellosis cases are caused by Legionella pneumophila, a ubiquitous aquatic organism that thrives in temperatures between 25 and 45 °C (77 and 113 °F), with an optimum around 35 °C (95 °F).[3]

Between 1995 and 2005 over 32,000 cases of Legionnaires' disease and more than 600 outbreaks were reported to the European Working Group for Legionella Infections (EWGLI).

70 to 80 °C (158 to 176 °F): Disinfection range
At 66 °C (151 °F): Legionellae die within 2 minutes
At 60 °C (140 °F): Legionellae die within 32 minutes
At 55 °C (131 °F): Legionellae die within 5 to 6 hours
Above 50 °C (122 °F): They can survive but do not multiply
35 to 46 °C (95 to 115 °F): Ideal growth range
20 to 50 °C (68 to 122 °F): Legionellae growth range
Below 20 °C (68 °F): Legionellae can survive but are dormant

 

[Paperdoc]

Don't rely on the marks. Do your adjusting based on measured temp at a a key faucet. I have found that a standard kitchen meat thermometer covers the right temperature range - from 120 to 180 F. Beware the scalding thing, though. Depends a lot on who's in the house. Many parents of young children (and also homes with very elderly people) deliberately run the hot water tank cool to prevent scald burns, ven though this is NOT the ideal for dishwashers.

 

[iGas]

Don't rely on the marks. Do your adjusting based on measured temp at a a key faucet. I have found that a standard kitchen meat thermometer covers the right temperature range - from 120 to 180 F. Beware the scalding thing, though. Depends a lot on who's in the house. Many parents of young children (and also homes with very elderly people) deliberately run the hot water tank cool to prevent scald burns, ven though this is NOT the ideal for dishwashers.

Uneducated treehuggers/people doesn't know that lowering temperature HWT is un safe, while suggesting it to prevent scalding & energy saving.

Better idea would be upgrade to TMV (Thermostatic Mixing Valve), or static mixing valve.