Re-reading my OP, it's a little confusing. Our old place had a gas water heater from the 90s. I flushed it every so often, without any noticeable buildup. It failed (leaked) a few years after we moved in.
The new place, our current place, has an electric water heater that's ~ 10 years old. The flushing and pictures are from this electric HW heater.
gathermewool...Do you have Well Water or Municipal Treated ?
We're on city water.
The current electric water heater has a round drain valve, with a concentric handle. I'll definitely consider replacing it with a more reliable fitting and ball valve the next time I drain and flush the tank.
I heard that Cooks don't use hot water from the tank for that reason.
Like if your making spaghetti or rice.
Use 'cold' water and heat it on a burner.
The concern isn't the sediment, which should settle out at the bottom of the tank and is mostly from sourced from the influent water (tap or well). The concern with consuming hot water is the heavy metal that leach from the sacrificial anode rod. This rod literally gives itself up to galvanic corrosion, so that the tank doesn't lose its own material and develop a leak. If you boat, it's the same principal as the sacrificial anode on your outboard (or I/OB), or any heat exchanger.
I tried to flush the water heater of my new place shortly after I moved in. A bit of mud came out, then nothing! I have a well and the water heater is so corroded with debris on the bottom that it's a lost cause. I'll just wait until it gives up then replace it.
I've heard of this before. If you've got a sump pump, bilge pump, some hose (and few other things), you could maybe loosen the existing drain valve and let it dribble into some intermediate container until empty; use some tygon hose and a pump to draw suction and drain the intermediate container; send effluent to a suitable drain. The supply must be off, of course, otherwise you'll be there literally forever!
Ensure you can loosen and tighten the drain valve to the heater a few times before you loosen it enough to drain, ensuring you don't end up with a valve stuck with only 2 threads engaged and copious amounts of water flooding your basement!
Have a normal drain hose connected, too, and try to work the valve open and shut while it's loose at the heater. Dripping dirty water from the loosened valve may clear just enough mud to allow continuous flow through the normal drain hose. At that point, you can flush normally, so long as it doesn't clog back up!
I've always filled my car wash bucket from the water heater drain when I make my car was water. I guess this is the same as flushing the tank because it drains the water at little bit at a time. I've never had anything come out of the water tank because it gets a few gallons drained from it monthly. I don't know if this is good or bad but it's how I've been doing it for years.
The main purpose of the water heater drain port is to drain the tank for replacement. The second purpose is to allow flushing of sediment and other particulates/sludge that accumulates in the bottom of the tank.
I personally wouldn't use the heater drain as my source of wash water, but since you're doing so frequently, there's likely very little abrasive sediment. So, you if you're not having any paint issues with your car due to abrasives, then you might be killing two birds with one stone - congrats!
Never had a gas water heater, always electric or via oil boiler?
But new to me house is gas. With water sensor next to it.
When you drain the water heater do you turn off the feed and drain the water from the tank, or just turn on the drain and let water flow through the heater and out the drain?
If you drain it, I assume you turn off the gas? How do they re-light? Or are they electric ignition these days. Heater is probably 5 yr old.
Previous place was gas; current place is electric.
I never flush a hot water heater hot. I always turn off the gas or open the breaker to let it cool down to a comfortably warm temperature, so I don't 1. have hot water spewing from a failed connection, causing a personnel hazard; or 2. damage my medium-duty garden hose.
The old HW heater in my old place had a pilot light that needed to be relit. Hold a butane lighter in a hole in the lower access cover (for this purpose) and turn on the gas.
The new HW heater in my old place has push-button ignition. Set dial to pilot and push button over and over until pilot lights.
New place is electric. Open/shut breaker.
Before I turn the AC on in the spring, I take drain hose off the AC drain and use it to flush the water heater. Only way I can remember to do it.
Smart way to think of it.