Step 1: Remove the bottom plate concealing the burner door and sight glass.
Step 2: Mark the temperature control, so you can return it to the original setting.
Step 3: Set the temperature and regulator dial to pilot lighting.
Step 4: Make sure your spark igniter is functional. Click it a few times, and check for spark through the slight glass.
Step 5: Hold down the pilot switch and spark the igniter until the pilot flame is lit. Continue to hold the pilot switch down for 30 seconds to 1 minute. Once the pilot switch is released, the pilot flame should stay lit. If it goes out, the thermocouple, temperature cut-off switch, or gas control may be at fault.
Step 6: Turn the regulator valve to the on position. Turn the temperature dial back to the original setting. You’ve successfully lit your water heater!
Step 1: Determine the correct size and style of thermocouple for your water heater. Information, such as your model and serial number can help determine the correct replacement. Most heaters will work with a 24″ universal thermocouple.
Step 2: Close the gas supply off to the water heater.
Step 3: Remove the bottom plate concealing the burner door and slight glass.
Step 4: Disconnect the thermocouple, igniter wire, pilot tubing, and main burner supply.
Step 5: Disconnect the high limit, or temperature cut-off switch (TCO) wiring.
Step 6: Remove the screws holding the burner door in place. Then slide out the burner.
Step 7: Remove the thermocouple from the pilot assembly.
Step 8: Remove the old push fit adapter and replace it with the new one supplied with the thermocouple. Insert the new thermocouple into the pilot assembly.
Step 9: Reinstall the burner. Make sure the front of the burner goes into the slot or bracket at the bottom of the burner chamber.
Step 10: Reconnect the main burner, pilot tubing, and thermocouple. Start all connections hand tight to avoid stripping the threads.
Step 11: Reinstall the burner door and tighten the screws.
Step 12: Reconnect the high limit or temperature cut-off (TCO) wiring.
Step 13: Reconnect the igniter wiring.
Step 14: Turn the gas back on to the water heater, then relight the pilot.
Step 15: Fire the main burner. Test for gas leaks with a soap solution at the pilot and main burner connections. If you see or smell any gas, turn the gas off, and recheck your connections.
How to replace a temperature and pressure (T&P) relief valve on a water heater.
Step 1: Determine you have the correct replacement for your relief valve. Match the size, temperature, and BTU rating of the old relief valve. This information is located on the end of the relief valve.
Step 2: Turn the gas control to the pilot setting. This is so the water heater won’t fire while it’s being worked on.
Step 3: Close the cold water supply off to the water heater.
Step 4: Drain off roughly 5-10 gallons of water from the tank. This will bring the water level in the tank below the level of the relief valve.
Step 5: Remove the drip tube from the relief valve.
Step 6: Apply teflon tape to the threads of the new relief valve. In a clockwise direction, when the threads are face up and towards yourself.
Step 7: Remove the old relief valve with a wrench in a counterclockwise direction.
Step 8: Install the new relief valve hand tight first, and then the remainder with a wrench. Ensure the relief valve port is aiming directly down.
Step 9: Teflon tape, and reinstall the drip tube.
Step 10: Open the cold water supply only partially to allow the tank to fill slowly. This will help reduce water hammer.
Step 11: Open a hot faucet preferably at the highest point in the residence. Leave the faucet open as the tank is filling to purge all the air from the system. Once the faucet runs steady water without any air, the faucet can be closed.
Step 12: Open the cold water supply fully, and check for leaks.
Step 13: Turn your gas control back to the on position.
Step 1: Turn the gas control to the pilot setting. This is so the water heater won’t fire while it’s being worked on.
Step 2: Close the cold water supply off to the water heater.
Step 3: Attach a hose to the tank, and drain the water heater completely. To speed up this process, open a hot faucet to allow air into the system while it’s draining.
Step 4: Apply teflon tape to the new drain valve.
Step 5: Remove the old drain valve with an adjustable wrench or pliers.
Step 6: Install the new drain valve hand tight first, then the remainder with a wrench.
Step 7:Open the cold water supply only partially to allow the tank to fill slowly. This will help reduce water hammer.
Step 8: Open a hot faucet preferably at the highest point in the residence. Leave the faucet open as the tank is filling to purge all the air from the system. Once the faucet runs steady water without any air, the faucet can be closed.
Step 9: Open the cold water supply fully, and check for leaks.
Step 10: Turn your gas control back to the on position.
How to test a thermocouple’s voltage using a multimeter. Pilot light keeps going out? A faulty thermocouple may be the issue. Acceptable range for most water heaters is 17-32 mV.
Step 1: Disconnect the thermocouple from the bottom of the gas control.
Step 2: Set your voltmeter to millivolts (mV) and direct current (DC).
Step 3: Set gas controls for pilot lighting.
Step 4: Attach the positive lead (Red) to the bare copper, and the common lead (Black) to the end of the thermocouple.
Step 5: Light the pilot, and continue to hold the pilot switch down until maximum voltage is reached. Normal operation for most water heaters is 17-32 mV. If it falls below this range a replacement thermocouple may be needed.
Click your brand of water heater for the warranty validation page
The serial number of your water heater will be needed to validate the warranty and confirm the age of the heater. The serial number is located on the rating plate/sticker on the water heater. Please note that most GSW and John Wood water heater serial numbers will work on the AO Smith warranty validation page.
Water heater not delivering as much hot water as it used to? Your heater’s dip tube may need to be replaced.
What is a dip tube?
The dip tube is a tube that is installed on the cold water supply of a water heater. It brings the incoming cold water to the bottom of the water heater to be heated, while the hot water is drawn of the top of the tank.
Signs you might need a replacement dip tube.
The most common sign that you might need a dip tube replacement is that the shower/tub hot water supply is not lasting as long as it used to. Another sign of a faulty dip tube is having small pieces of plastic clog up aerators on your faucets. This is a sign that the dip tube is deteriorating and pieces are starting to break off.
Here’s a example of a broken or damaged dip tube. When the dip tube is broken off near the top, as in this picture, the cold water supply is able to short circuit over to the hot side before being heated at the bottom of the water heater.
What is the best way to pipe multiple water heaters? We get this question quite often.
Most of the water heaters that we see out there are piped in series. We strongly recommend running water heaters in parallel, but both have their benefits and downfalls.
Piping in series is when the cold water supply enters the cold side of heater #1 and then exits out of the hot side of heater #1. Then it enters into the cold side of heater #2 then exits out of the hot side of heater #2 to feed the demand. The main concern in this setup is that heater #1 usually has a higher demand on it. We see this constantly, as the first tank usually is always first to fail. If piped in series, it is best to have the first heater set to a lower temperature then the second. This reduces the stress on the first heater. The main benefit to this setup is ease of installation and cost.
Piping in parallel is when the cold water is piped in to the cold inlets of both heaters symmetrically. The water is then piped out of the hot side of each heater symmetrically as well. The reasoning behind piping the tanks symmetrically is to ensure both tanks are being filled and drawn from evenly. Both heaters should have isolation valves as well. There any many benefits to this setup, including the ability to run one heater at a time easily by isolating the other. This ensures in the event of a heater failure you will still have a hot water supply from the alternate heater. Another great benefit is maximizing output of the heaters. Piping in parallel gives you the full output of both heaters, as they are working as a team.
Example: Two 50 US gallon water heaters at 40,000 BTUs each, will now give you 100 US gallons at 80,000 BTUs. That’s a lot of hot water!
50 US gallon John Wood water heaters piped in parallel.
At The Hot Water Tank Company we choose to go green! All of our water heaters are recycled and saved from the landfill. We also recycle all of our cardboard, scrap copper and brass. By choosing The Hot Water Tank Company you’ll know that you’re helping to reduce, reuse, and recycle.
A well-maintained anode rod in a water heater can help prolong the life of the heater and save you $$$.
When corrosion or absorption occurs in the water heater, the anode rod helps protect the metal tank. The corrosive properties of the water will attack the anode rod before attacking the steel tank of the water heater. This is why we hear the term “sacrificial anode”. Anode rod life depends on water quality and consumption. Most anode rods are made from magnesium or aluminum. Here’s a quick video on replacing an anode rod.
Born in small town Antigonish, Nova Scotia, Canada, I had a passion for anything mechanical. After receiving my Red Seal plumbing ticket, I founded The Hot Water Tank Company Ltd., a service plumbing company. After helping people with their hot water issues for years, I decided I wanted to be able to reach a broader audience. To that end, I created My Hot Water, an informational page intended to assist homeowners to make educated decisions about their hot water issues. My Hot Water provides expert advice and information to homeowners looking to choose trusted, local contractors, or looking to save money by tackling the job themselves.