10 Common Boiler Problems

Boilers are hearty and reliable performers. This is why many people choose them to handle their wintertime heating needs. But they have a heavy load to handle, and over time they can exhibit noticeable signs of malfunction or declining efficiency.

Here are 10 common problems that might indicate your boiler needs repair or maintenance:

#1 Pilot light has gone out

A draft that penetrates a pilot light enclosure can blow it out. A broken thermocouple that cuts off the supply of gas can also extinguish the flame.

When your pilot light is out, call your HVAC contractor and let them know you need some help. They will send a technician to your home to diagnose the trouble.

#2 Kettling

Lime (calcium) buildup inside your boiler can be a problem over time. When buildup is excessive it will inhibit water flow through the heat exchanger, causing the water to overheat and boil. When this happens, you’ll hear a gurgling or rumbling sound, similar to that caused by a boiling tea kettle.

A plumber can solve your problem using a procedure called a power flush, which will dislodge sludge and/or calcium buildup if it is present. They will use specialized equipment to clean out your boiler system quickly and completely.

#3 Banging, screeching, whistling or gurgling sounds

Air in the system is the most common reason for this noise. But these sounds may also be a sign of impending pump failure, or early symptoms of a kettling problem that will only get worse with time.

If these noises are persistent you might try bleeding your radiator. This is a simple procedure that can remove any excess air from the pipes. If kettling is suspected, you can have a plumber perform a power flush. Should the strange noises continue, contact your HVAC contractor to arrange an inspection.

#4 Pressure is low

You’ll know your pressure has declined to unacceptable levels if the pressure gauge drops below one. This can be caused by water leaks, a failing pressure valve or by a recent bleeding of the system.

If the latter can be ruled out, you should call your HVAC contractor to ask for assistance.

#5 Leaking is spotted

Pipe leaks and fissures in the water tank can be caused by rusting and age-related corrosion. Meanwhile, broken pump seals and pressure valves may cause leaks to develop inside the boiler.

Water leaks need quick attention. If you notice one anywhere around your boiler you should summon a professional to assess the damage and make the required repairs.

#6 Boiler turns on and off too often

A boiler that cycles on and off too frequently might be affected by low water pressure, or by a faulty thermostat. If a valve that should be opened was somehow closed, that could cause rapid cycling as well.

You can check all the valves yourself to make sure they’re open. It’s also a good idea to call your local water company to see if other customers are experiencing low water pressure (meaning the source of the trouble is outside your home). Otherwise, a boiler that keeps turning off unexpectedly should be examined by a professional.

#7 No or limited heat coming from the radiator

Air in the system or rust buildup inside pipes can prevent proper heat flow in a radiator. A failing water pump could also be the culprit.

Bleeding the radiator might solve the problem. A lack of heat from the radiator may also be a sign that a power flush is needed. But if those procedures don’t work, it’s probably time to call your HVAC contractor to arrange for an inspection of your entire heating system.

#8 Thermostat doesn’t seem to function properly

If the temperature in your home is higher or lower than you expect despite unchanging thermostat settings, the thermostat may be responsible for the problem. A failing thermostat will often reveal itself through short cycling (the boiler turning on and off frequently).

Bad batteries can cause thermostat malfunctioning. So, you should try replacing the batteries before you replace the thermostat itself. But if the performance of your system remains erratic, you should probably upgrade to a better-quality unit.

#9 The condensate pipe is frozen

Waste water is carried away from a boiler by PVC pipe that empties outside. Unfortunately, the pipe is vulnerable to freezing in harsh winter conditions, and a frozen condensate pipe will prevent proper drainage and cause water buildup inside the boiler.

If your boiler seems sluggish and you can see your condensate pipe isn’t draining, you may need the assistance of a trained professional who can locate the frozen spot and thaw it out. You can try pouring hot water on the outside section of the pipe to see if you can unfreeze it yourself, but you can’t count on that working.

#10 No heat or hot water at all

While there could be a simple explanation, in most cases a total boiler breakdown means serious mechanical problems have developed. Consequently, your problem won’t be amenable to DIY fixes.

Assuming the breakdown occurs in winter, you should call your HVAC contractor immediately and let them know you have an emergency.

Boiling Mad at Your Boiler? Let ABE Come to the Rescue

If you see any signs of trouble with your boiler, don’t lose your cool. Instead, contact us at ABE Heating and Cooling right away to request assistance. Our trained technicians can diagnose the cause of your boiler’s odd or dysfunctional behavior and implement solutions that restore your heating system to top working order. We are located in Brighton, Colorado and serve the entire Denver Metro Area, and we are ready to handle your heating and cooling emergencies as soon as they arise.