Instructions on How to Drain a Water Heater Fast and Improve Performance

Water heater serviceImage by Steve Buissinne from Pixabay

Why and how to drain a water heater properly? Does it help to fix the common water heating problems? How often should it be performed? Should I flush the tank as well?

Check out this step-by-step guide to drain a water heater fast and efficiently and ensure better performance. Draining tips and tricks, and how to deal with the problems.

Every manufacturer, plumber, and expert recommends draining a water heater due to its benefits: better performance, efficiency, desired power output, longer heater life, safer operation, and savings.

This article covers only gas water tank heaters as the draining procedure is slightly different from the electric and tankless models.

Use this article that talks about maintaining electric water heaters and draining tips.

Benefits of draining a water heater

Brass drain valveBrass drain valve
(photo: amazon)

The main reason to drain a water heater and flush the system is to prevent or remove the sediment build-up and dirt that can collect at the tank's bottom, reduce the performance and efficiency, and increase operating costs.

This is happening because of the imperfect conditions one tank can be exposed to (hard water, mineral content, and rust, for example), so regular maintenance should be applied.

Another reason for draining is the heater's inactivity - during the long vacation, for example, so if the unit is subjected to freezing temperatures during the winter, the heater and piping should be thoroughly drained and the drain valve left open. If you have an on-demand unit, check out an article on how to winterize a tankless water heater.

Probably, the biggest problem that can happen to one home is the tank leakage and water damages that can cause to the surrounding, especially if the water heater is installed in the attic, above the living space.

Leaking is usually the result of loose connections, corrosive action in the tank, or broken elements. Draining will reduce or eliminate the danger of leaking and make the service and replacement viable without further damage.

Note: Even if everything runs well during draining, there may be some spillage when disconnecting the hose.

What you will get after this draining process is cleaner water, lower utility bills, and a longer lifespan.

Avoid water damages by installing a drain pan

During the water heater installation, install a drain or catch pan under it to collect the occasional dripping either during the condensation from the heater's tank, TPR valve, or pipe joints at the top of the unit.

The recommendation is to use a metal drain pan with an outside diameter 2" bigger than the tank diameter and pipe it to an adequate drain to prevent overflow and leakage. If the water heater is installed in the attic, the drain pan must be provided. A small device can also be installed under the water heater to alarm when there is a leak.

How can I drain a water heater fast?

The best way to drain a water heater quickly and safely is by using the utility pump. Check out the pump specs to see how many gallons per hour of water can be transferred, the power of the motor, and the maximum water temperature it can deal with.

The recommendation is to buy a portable electrical pump with at least 1/2 HP and the 12 V battery operated one, in case of an emergency and when the electricity is unavailable.

Note: As the sediment buildup can obstruct the normal water flow, consider replacing an existing drain valve with the ball valve.

If the water heater is installed in the basement - below grade, and there is no floor drain, use the electric pump to move the water outside. Attach one end of the hose to the utility pump and the other end from the pump to an area away from the house. If water is not too hot, you can direct a hose into the sump pit or a sewer system.

emergency plumber

What to do if water is still leaking

Keep in mind that water leaking mostly develops slowly - it is quite unusual to see that pipe or connection bursts. If the puddle of water is noticed nearby or under the unit, immediately turn the water, gas, and electricity OFF on the main valve/switch, to prevent the damage from the leaky unit and either call the professional plumber or make sure to fix it.

Step-by-step guide on how to drain a water heater fast

Gas water heaterGas water heater
  • Turn off the gas at the gas control valve or manual shut-off valve located close to the heater.
  • Close the cold water inlet valve.
  • Open the closest hot water tap to vent the heating system.
  • Use the garden hose and connect it to the drain valve located at the bottom of the heater.
  • Use the other end of the hose and discharge to an adequate drain so it won't cause any damage or injury.
  • You can also use a bucket for this purpose if draining through the hose is not applicable.
  • Open the drain valve on the water heater and let all the water drain from the tank. Be careful as water might be hot. This is the reason to use the appropriate hose type.
  • Once drained, flush the tank as needed to remove deposits.
  • To refill the tank, close the spigot and follow the instruction on how to start the heater.

You can also use a video below.

Should I drain a water heater often?

The recommendation is to drain and flush the tank every 6 months, or at least once a year, as part of the regular, recommended maintenance. If it is the first time to drain, and there is a lot of sediment buildup in the tank, the drain valve won't work or will clog up, so you won't be able to close it entirely, resulting in some leakage afterward.

Since most water heaters come with plastic and low-quality drain valves and if it is hard to clean it up, or if it gets broken, use the hacksaw blade, hammer, and a screwdriver to saw and chip out the broken pieces and replace it with the ball valve for easy use and maintenance afterward.

If nothing comes out, then the water heater is in excellent condition.

Tips when draining a water heater

One of the ways to prevent lime and sediment buildup is to install a water softener or apply a de-limer solution. This is an additional cost for your budget, so regularly draining and flushing a water heater is the cheapest and simplest solution.

The pressure release valve needs to be open so that air will get into the tank and water can drain out smoothly. The other way is to open a faucet.

To prevent the risk of burns due to the scalding temperatures, open a hot water tap to allow sufficient cold water to enter the tank and lower the temperature.

Don't be surprised if you see dirty or brown water. This is because of all the minerals and sediments that had built up or due to corrosion.

The floor drain must not be clogged and should be easily accessible to allow trouble-free operation and service.

Flush the rest of the sediments out by turning on the water to the tank, and when the drained water is clear, you are done. Use a bucket for this purpose.

When you drain a water heater, the discharge line must pitch downward from the valve to completely drain by gravity. When filling up the heater, keep the drain valve closed.

How long does it take to drain a water heater?

The time needed to drain a water heater depends on the tank and hose size, and pressure, but as you could see, it is very simple, and the procedure can last from a few minutes to over an hour if it gets complicated.

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