Why is My Heater Leaking Water?
TechXpert verified by Ken Kontra
Your heater could be leaking water for a number of reasons, from a condensate leak to a heat exchanger defect, depending on the type of system you have. If your heater is leaking water, don’t wait until the problem is too hot to handle –– you’ll want to diagnose the cause and have it fixed right away.
Types of Heater Leaks
You’ve got a variety of heaters to choose from, but no system lasts forever. Over time, your heater may hit a bump in the road and start leaking water, telling you it’s time for repair.
Here’s a rundown of common heating systems and where leaks are likely to come from:
Notice a pool of water around the base of your high-efficiency condensing furnace? It’s likely due to a condensate blockage or a component that has failed. In other cases, water around your furnace might come from a clogged or broken humidifier or damaged plumbing pipes.
Old age is a main cause for leaks in your radiator. Over time, your radiator can rust and corrode, especially if you’re not topping up chemical inhibitor levels regularly. Corrosion will carve out small holes at the bottom of your radiator and create a direct passage for water to leak out onto your floors.
Another reason your radiator is leaking? A loose or damaged spindle (the part that connects your radiator to the radiator valve). If it’s loose, all you need to do is tighten the gland nut. If it keeps leaking, you can wrap the spindle with PTFE tape as a temporary fix.
A boiler leak can be difficult to detect, especially if it’s leaking from inside of the boiler jacket. However, if your boiler is leaking from the bottom – similar to a radiator – its pipes or water tank may be corroded. So, you can look for rust to help diagnose the issue.
An improperly adjusted water auto fill is another cause of a leaking boiler. Average boiler pressure is 12 to 15 psi, and if the gauge needle on your boiler reaches 30 psi, the pressure relief valve will begin to open and relieve that pressure. If this happens, you may need to adjust the auto fill and check the expansion tank.
The leak could also be coming from your boiler’s temperature valve, which may indicate there’s an issue with the temperature probe in your boiler.
What to do When You Notice a Leak
When your heater starts leaking water, you’ll want to contact an HVAC technician to diagnose and fix the issue.
In the meantime, you should shut off the system and clean up any water around your heater that could cause water damage. It’s also smart to check your system’s air filters to see if they need to be replaced. Addressing a leaking heater right away will help you sidestep future problems and damage to other parts of your home.
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