If your hot water heater is leaking, a leak from the top is by far the best scenario. A leak that is originating from the top of a water heater, if caught in a timely manner, is almost always repairable. However, if not fixed promptly, these types of leaks can lead to serious and costly damage, as water travels down the exterior of your water heater.
If a water heater leaking from the top is left unrepaired, water could enter the electrical component compartment, and cause an electrical short to develop. Another possible problem that could develop is water damage to the floors or walls surrounding your water heater. If you suspect your water heater is leaking, it’s important to address the issue as soon as possible.
Find the Leak
A leak from the top of your water heater is generally a pretty easy fix, and of course, your first step is to find where the leak is originating. It’s always a good idea to turn off the power before working on your water heater.
Gas water heater – Turn off the gas by turning the thermostat control to the OFF position.
Electric water heater – Turn off the electricity by switching the circuit breaker on your electrical panel to the OFF position.
Once the power is off to the unit locate the cold water inlet. This inlet allows water to enter the tank to be heated, by leaving the valve ON a leak will be easier to find. Dry the area and use a paper towel to help you spot the leak if you are unable to see water seeping. Check the pipes and seals for water leakage. Once you locate the leak, turn the cold water inlet to the OFF position. This will help prevent any further water damage.
Common Causes when your Water Heater is Leaking from the Top
Cause #1: Water inlet valve
A pool of water on top of your water heater is often an indication that there is a leak with either the water inlet or outlet pipe. First, check the cold water inlet pipe. There is often a gate valve or an in-line valve that will allow you to turn the water off to your water heater. An in-line valve has a lever to turn the water on or off. When the lever is parallel with the pipe, the valve is open and allowing water to enter the tank.
Check the valve for leakage. If you notice that it is dripping, the solution may be as simple as tightening the nut that connects the handle. If after tightening the nut, the valve is still leaking, it may be that the valve is faulty and needs to be replaced.
Cause #2: A loose pipe fitting
Take a close look at the water inlet and outlet fittings to see if there is any water leaking. Look closely at the point where they connect to the water heater and other fittings. If you find your leak is coming from one of the connection points, try tightening the pipe with a wrench as it could simply be a loose connection.
It’s not uncommon to see these fittings become corroded. If this is the case you may need to replace the fitting itself. However, it could also be an indication that there may be a more serious problem with your tank. If you find you need to replace the fitting, it is generally not a difficult task, although they can sometimes become difficult to remove. Some water heaters use copper tubing instead of
Replacing a fitting is generally not a difficult task. Although they can sometimes be a challenge to remove. Some water heaters use copper tubing instead of threaded pipe, and unless you are comfortable working with copper, you may want to contact a qualified plumber.
Top Cause #3: Temperature & Pressure Valve
The Temperature and Pressure Relief Valve (T&P valve) is generally located on the side of the tank but occasionally is on the top. Look closely at the valve to see if there is any water leaking out from the valve. If water is leaking from the threads of your T&P valve, then you’ll need to remove the valve in order to determine if this is the issue. As a general rule, if this is the problem, it is best to replace the T/P Valve with a new one. These valves are installed for safety and it is best not to take any chances.
- Drain the tank until the water level is below the valve (click here to learn how to drain your water heater).
- Open a nearby hot water tap to let air into the tank.
- Use a pair of channel locks to unscrew the valve from the tank.
- Check for rust or corrosion on the tank by inspecting the hole where the valve had been located. If you find any rust or corrosion, your water heater will need to be replaced.
- If there is no visible rust or corrosion, wrap the threads of the valve in Teflon tape, to help seal the valve. Then screw the water heater pressure relief valve back into the tank.
After performing any repairs to your water heater, it is important to closely watch to see if the problem persists. If the leaking continues, you should call a professional plumber.
See our complete guide on how to deal with a leaking water heater. Click here
Other Possibilities Why Your Water Heater Would Leak on Top
- If you have a gas water heater, it is possible that rainwater has traveled down the flue vent pipe and collected on the top of your tank. This may occur particularly during a storm with high winds.
- Another cause could be condensation. It’s normal to see a small amount of condensation on the exterior of your water heater. However, if your water heater is not able to meet the household hot water demand, you may notice more condensation than normal. This is because the moisture is not allowed to dissipate since the tank is too small for the demand of hot water.