If your home is heated by a gas boiler furnace, you may notice that it is no longer heating your home properly. Also, you may have started hearing strange noises coming from the furnace. If so, you can determine the cause of the problem by listening to the volume and characteristics of the sounds it is making.

Low Rumbling After The Burner Lights

If you hear a low rumbling coming from your boiler, this is known as kettling, which is caused by a buildup of limescale inside the heat exchanger. To find out of this is the possible cause, turn the thermostat down until the furnace turns off. Wait for about 15 to 30 minutes to let the heat exchanger cool off, then turn the thermostat back up until the boiler kicks back on.

Once the burner lights, listen carefully for any rumbling. If so, there is probably limescale coating the exchanger, making it more difficult for it to heat the water up. This scale is caused by the deposit of minerals from the water. 

If you believe kettling is the cause of your boiler's noises, you can try to remove it yourself. However, if you do not feel comfortable doing so, you may want to have a boiler repair service like Robinson Heating & Cooling Inc examine the furnace and do the job for you.

Loud Whistling When Water Is Running Through The System

When you hear a loud whistle coming from the furnace, listen to see if you hear water running through the system at the same time. If so, there are two possible causes of this noise.

The first possible cause is that the water pressure in your boiler's system may be too low. When it is too low, the water is unable to push its way through the pipes with enough force to fill the tank. When this happens, it can create a whistling sound as it tries to sluggishly pass through the pipes. If this is the cause, a repair service may need to replace or adjust the pressure valve.

The second possible cause is that there could be a small leak in one of the water or steam pipes. When this occurs, the hole provides a small escape portal for either the water or air, and as it passes through, it can cause a whistle. If this is the case, a professional may need to either seal or replace the pipes.

Sharp Banging When The Water Pump Kicks On

Another noise you may hear is a sharp banging when the boiler's water pump kicks on, followed by the sound of trickling water. If this is what you are hearing, one possible problem is that your furnace's pump is starting to go bad. When this happens, it is unable to properly circulate the heated water, making the furnace unable to heat your home. If this is the problem, the pump will need to be replaced.

A second possibility for the cause of the banging is that the water pressure is too high. When the pump kicks on, the water is forced too hard through the system. If this goes unrepaired, this excessive pressure could eventually blow holes in the pipes or damage the water pump. A professional will need to readjust the water's pressure valve.

Using the above guide can help you determine the problem with your furnace. However, if you are unable to find the probable cause, or you are unsure of what to do once you know what it is, you may want to contact a boiler repair contractor to have a professional look at your furnace and offer you possible solutions for fixing it.