How to Replace Drain Valve on Water Heater

How to Replace Drain Valve on Water Heater

Every home needs a reliable water heater to deliver a consistent supply of hot water for a number of domestic functions. Water heaters, like all mechanical systems, wear out over time, demanding maintenance and infrequent repairs. Faulty drain valves are a typical problem for homeowners since they can cause leaks, reduced efficiency, and the need for costly repairs. How to replace the drain valve on the water heater? This detailed article explains how to replace the water heater’s drain valve step by step.

What Is The Drain Valve?

A water heater drain valve, which is a small valve positioned at the base of the heater, allows water to be drained from the tank for cleaning and maintenance.

It is found on both gas and electric heaters and has two threaded ends (usually 34″ in diameter), one of which is put into the heater and the other to which a garden hose is attached (for draining). The valves may have a screw head or a handle with a hand grip for opening and shutting. The valve on more expensive devices is constructed of brass, while the valve on less expensive devices is made of plastic.

Also, Read: Why Is My Hot Water Heater Leaking Water?

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Where Is The Water Heater’s Drain Valve?

Your water heater’s drain valves are toward the bottom; depending on the model, they may be slightly to the right or in the middle. Residential heat pump water heater drain valves are frequently positioned in the unit’s center, whereas gas and electric water heater drain valves are typically located to the right or left of the unit.

Storage tanks and tank-style commercial and domestic water heaters are the only ones that have drain valves.

Because tankless water heaters can not keep vast amounts of water like traditional tank-style water heaters, they do not have a separate or dedicated drain valve. Isolation valves or service valves with built-in purge drains or threaded ends that can be connected to hoses to flush the tankless water heater are commonly used in tankless systems.

Types Of Drain Valves:

There are two types of drain valves:

Copper Drains:

Although they are becoming more prevalent, they are most typically found on “proline” water heaters or a manufacturer’s product line offered only to supply businesses. We recommend that you check to see if your equipment has a ball valve or this type of drain valve.

Plastic Drainage Valve:

These are the cheapest and most problematic drain valves; they are often found on water heaters purchased from a hardware store.

When Should I Replace the Drain Valve on My Water Heater?

If your water heater’s drain valve is leaking or not allowing appropriate flow when draining the tank, it should be replaced.

Obstructive Garbage:

A jammed valve with debris and silt, on the other hand, indicates either poor water quality or insufficient tank flushing. Because most factory-installed water heater drain valves are not designed to be easily replaced, the complete valve should be replaced.

Leaky Valve:

A leaking drain valve should be fixed as well. Plastic drain valves deteriorate with time and become brittle. Plastic that has lost its tensile strength is prone to fracturing and leaking. Dribbles and drips from your hot water tank could be caused by worn gaskets and seals in addition to worn gaskets and seals within drain valves.

The most dependable cure for a Leaky Valve is to replace your water heater’s Drain Valve. To halt the leak, try slightly tightening the existing drain valve. Avoid over tightening the drain valve. This could aggravate the leak or place a plastic valve at risk of bursting; oh no!

Sluice For Copper:

If the brass valve in your hot water tank is leaking, you can try to fix it by changing the gaskets. We do not, however, recommend conducting this repair on plastic drain valves.


To replace the drain valve, the following tools are required:

  • A ratcheting wrench.
  • A thread sealant for pipes.
  • Use Teflon tape to seal a surface.
  • Newly developed drain valve.
  • The drainage hose.

Also, Read: What Size Tankless Water Heater For Family Of 4?

How Would You Replace a Water Heater’s Drain Valve?

Drain The Water:

Drain the water heater to prevent flooding. Ask a volunteer to gather the water and put it in a bucket for disposal. You can reattach the valve once you’ve added enough water to it.

Shut Off The Valve:

Close the valve to stop water from entering the pipe while you empty it. Turn off the heater’s gas valve to stop the water from re-heating. Give the water in the water heater some time to cool. Pipe wrap should be used to cover the new valve’s threads.

With the wrench, open the valve.

Unscrew The Tank’s Valve:

A pipe wrench is an ideal tool for this task. Request that your aid gather the dripping water in buckets. Carefully remove the valve.

Remove The Accumulation:

To remove any mineral deposits, slowly insert the screwdriver into the hole.

Put In the New Valve:

Insert the replacement valve into the hole to complete the installation. Screw the valve in after you are satisfied that it has been properly positioned. Check that it fits snugly and does not leak.

Examine the valve:

To confirm that the valve is working properly, open and close it several times. The pressure release valve must be closed. The water supply valve must be turned on.

Water Heater Maintenance:

Regular maintenance extends the water heater lifespan, and drain valve issues can be avoided. Inspect for rust and leaks before draining and cleaning out your tank every year to remove sediment collected at its base.

To keep your water heater functioning optimally, it is advisable to get professional maintenance performed every few years.


Clogged or malfunctioning water heater drain valves can wreak havoc with your heating system or cause minor leaks, so following all regulations is key to staying safe and sound. In particular, gas water heaters must always be switched off before being installed in any new location.


How much does replacing the drain valve of a water heater typically cost?

Typically, replacement drain valves for water heaters cost $100-$200. Because regular maintenance must occur on these tanks, having drain valves that allow tank evacuation is necessary.

Does every water heater include a drain valve, and what are its goals?

A drain valve is standard equipment on all water heaters; however, most people who purchase these appliances never adjust it themselves.


About Author

Mobeen Shahid

Mobeen Shahid

Mobeen Shahid is a Mechanical Engineer with two years of experience in the HVAC industry. His passion is analyzing HVAC issues, and he works relentlessly to devise customized solutions. He has been in the industry long enough to know the ins and outs and ensures that areas are optimally heated, cooled, and ventilated.

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