3 Things That Can Go Wrong With A Hot Water Heating System

Hot water heating systems come in two general flavors: convective and radiant. Both systems work similarly in modern homes, but their method of heating varies. Convective systems use low-profile baseboard heaters to heat the air, which then circulates around the room. Radiant systems use radiators to heat objects and people in the room directly via radiation.

While the endpoint heating methods differ, both systems use relatively similar designs and plumbing. Some homes may even have a mix of baseboard and radiant heaters, although typically not on the same zone circuit. Regardless of which type you have in your home, you should know these three potential failure points with your hot water heating system.

1. Expansion Tank Problems

Hot water expands as it heats, increasing the pressure in your hot water plumbing. Your system needs to maintain enough pressure to fill the pipes, but too much pressure can damage fittings or cause other long-term problems. If the pressure increases too much, you'll find water near your boiler's pressure relief valve, and you may even trigger a safety shutdown.

Modern hydronic systems use an expansion tank to avoid problems with normal pressure fluctuations. A failing tank can cause your system pressure to rise, triggering the relief valve each time the heat turns on. You may also lose pressure (and heat) if there's an internal failure in the tank. In either case, you'll need a technician to examine it and determine if it's causing your pressure problems.

2. Failed Zone Valves

If you have more than one thermostat in your home, you also have zone valves. Zone valves allow individual sections of your home to request heating, opening and closing separate heating circuits as necessary. Hot water cannot flow into a zone circuit without the zone valve allowing it, so problems with these components can significantly impact your home's heating.

You can usually recognize a zone valve problem when you have heating issues with only one section in your home. If one zone stays cold all the time, the valve may be stuck closed, or there may be an issue with the thermostat or the wiring. On the other hand, a zone that's too hot can indicate a zone valve that's failed in the open position, allowing hot water to circulate to your heaters continuously.

3. Broken Circulator Pumps

The circulator pump keeps hot water flowing through your house. A failed circulator pump can stop your system from heating your home at all, or you may notice that only the heaters closest to the boiler get hot. Circulator pumps can develop numerous issues, some of which may be repairable, and others will require a technician to replace the unit.

Since the pump is one of the more complex elements of a hydronic heating system, it's usually a good idea to rely on expert help. A professional technician can help you understand why your pump failed, address any other underlying issues with the system, and prevent future pump failures. Contact a local heating service to learn more.