Proper way to flush a Hot Water Heater..

Users who are viewing this thread

Phillbo

Member
Messages
103
Reaction score
0
Points
16
Location
Arizona
Hello all. I had a new Electric Water Heater installed last year and the plumber that installed it recommend I flush it each year.

Is there a right and wrong way to do this? Do I just turn off the water to it and let it drain or do I need to drain it with the water supply turned on still? Kill the power to the unit at the breaker as well?

Is this really necessary?
 
Last edited:

Reach4

Well-Known Member
Messages
39,029
Reaction score
4,484
Points
113
Location
IL
Water heater (WH) flushing can be done different ways. The simplest is to
1. Turn off the WH water, and put the WH in vacation mode, if it has one. Otherwise off.
2. Open a hot water tap to pass air.
3. Drain the WH completely. Usually you would use a hose to direct the water. (Take a look at the first water; it may be impressive.)
4. Turn the water supply on fully for a few seconds, and turn off. You are trying to cause turbulence to the bottom of the tank.
5. Do steps 3 and 4 several times. If you have a way to monitor the drained water, you could judge by what you are getting out.
6. Turn on the water and expel the air. Close the hot water tap once the air has been expelled and just water is coming out.
7. Turn the WH back on. It is not that critical with gas, but it is important that the water level is above the top element before turning the power to the WH back on.
 

Reach4

Well-Known Member
Messages
39,029
Reaction score
4,484
Points
113
Location
IL
Thank you. Is it critical to do a flush every year?
No. Most people don't flush even every 10 years. However if they do after 10 years, and see what comes out, they will be inspired to flush more often.

If you have a whole-house cartridge filter, there may not be anything to flush. But with a well, and even city water, without a whole house cartridge filter, flushing is a good idea. Maybe do it after a year, and watch what comes out. If nothing observed, put it on your calendar to do it in 3 years.

You should have seen what I got out of my 12 year old WH. I don't know if it had been flushed previously, but it was impressive. Black. Small rocks. I now have sediment filters that would stop that.
 

Phog

Active Member
Messages
454
Reaction score
84
Points
28
Location
Rochester NY
Thank you!

Note step #2 -- open a hot water tap to pass air. This is actually an important step to remember to do. If you drain the tank from the bottom without leaving a way for air to get in through the top, a negative pressure will develop inside. At worst case this could cause the tank to "oil can" and crumple inward. Very unlikely but worth mentioning.
 

Master Plumber Mark

Sensitivity trainer and plumber of mens souls
Messages
5,540
Reaction score
358
Points
83
Location
indianapolis indiana - land of the free, home of
Website
www.weilhammerplumbing.com
I disagree with all of you... draining a water heater is a waste of time.....
especially if you are turning off the water to the heater.....

I tell my customers to "power flush " the heater....
1 You simply leave everything on with normal pressure... dont turn off anything

2 you put a hose on the bottom faucet and secure it in a drain or out on
the driveway....

3. you turn on the faucet --full on-- and let it blow out the hose for about 20 seconds
then you turn it off ... then you turn it on again and repeat this procedure maybe 20 times to
stir up the sediment on the bottom of the tank and blow it out the faucet....

Think of it like trying to piss out a kidney stone.... with no pressure and everything staying
static in the tank,, nothing moves.,, nothing gets stirred up.... and it just mostly lays on the bottom.....

With full pressure the dip tube stirs up everything as much as it can and with the faucet open it
should mostly blow out the end of your hose..... (or pecker)





 

Dj2

In the Trades
Messages
2,611
Reaction score
258
Points
83
Location
California
I never flush, but after 6 years I recommend to start putting money aside for a new WH.
 
Top
Hey, wait a minute.

This is awkward, but...

It looks like you're using an ad blocker. We get it, but (1) terrylove.com can't live without ads, and (2) ad blockers can cause issues with videos and comments. If you'd like to support the site, please allow ads.

If any particular ad is your REASON for blocking ads, please let us know. We might be able to do something about it. Thanks.
I've Disabled AdBlock    No Thanks