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Flushing water heater

Explorer II
Explorer II
When I drained the water from the RV last year, I noticed some soft white sediment on the pipe plug for the water heater drain. I said to myself, "I should flush the water heater next time I drain it." Then, of course, I stopped thinking about it, "next time" being in the future.

The time has come; we're expecting a cold snap next week, so I want to drain the fresh water, blow out lines, etc.

Is it adequate to turn on the water pump and use that to flush out sediment? Looking the topic up on Google offers all kinds of possibilities, but I trust this group's knowledge base more than I trust random internet pages.

MDKMDK wrote:
You might want to introduce some white vinegar into the tank for a short period to help break up the calcium/lime deposits if they're bad. If you have the time to spare?

After we arrived home from 6 months in AZ I used 4 gallons of vinegar and 4 gallons of water to soak in the fresh water tank after running though all the lines with the water tank full. I always wondered if I was the only one doing this. retired from rving Chevman
2019 rockwood 34 ft fifth wheel sold
2005 3500 2wd duramax CC dually

KSH 55 inbed fuel tank

scanguage II
Induction Overhaul Kit
TST tire monitors
FMCA # F479110

I made my own tube flusher when I had a water tank that needed to be drained. Garden hose pressure will work fine and allow that white calcium to wash out. You will be surprised on the amount you have laying in there.
Stacey Frank
2016 Tiffin Allegro Bus 40AP
2019 Tesla Model X
2015 Cadillac SRX we Tow
1991 Avanti Convertible

Garden hose pressure with the wand designed for that is the best way to go, like bukhrn said. 10 minutes and you're done.
John & Gloria
South West, Florida
2009 Leisure Travel Serenity

With the tank full, but pressure released:

Remove the drain/anode plug.

Insert one end of a 5' section of cheap clear plastic hose of a diameter about 3/4 that of the tank threads.

Suck on the other end to start a siphon. Move the tank end around, "vacuuming" the bottom of the tank. Being clear hose, you will be able to see when to move the hose and when you are getting no more debris out.

If it hasn't been done in a long time, may need to use the potable water pump ON to refill and repeat "vacuuming".
Brett Wolfe
Ex: 2003 Alpine 38'FDDS
Ex: 1997 Safari 35'
Ex: 1993 Foretravel U240

Diesel RV Club:

I use a shop vac with a 1/2" hose in its end to clean mine out.

You might want to introduce some white vinegar into the tank for a short period to help break up the calcium/lime deposits if they're bad. If you have the time to spare?
Mike. Comments are anecdotal or personal opinions, and worth what you paid for them.
2018 (2017 Sprinter Cab Chassis) Navion24V + 2016 Wrangler JKU (sold @ ????)
2016 Sunstar 26HE, V10, 3V, 6 Speed (sold @ 4600 miles)
2002 Roadtrek C190P (sold @ 315,000kms)

Any type of flushing is better than not flushing. IMO, using a wand like posted above, will give best results, and is similar to what I use.


Explorer III
Explorer III
I use my water tank wand on my garden hose,
2007 Forester 2941DS
2014 Ford Focus
Zamboni, Long Haired Mini Dachshund