Any functioning boiler will naturally heat up as it runs, but if your boiler is too hot to touch, it could be a sign of a more significant problem. An overheating boiler may suffer permanent damage or even explode, so you should begin addressing the issue as soon as you notice it to prevent a hazardous situation. Follow these four steps to safely identify and correct the cause of your overheating boiler.
Shutting Off the Broiler
Whenever you suspect something may be wrong with your boiler, shut off its supply of gas and water immediately. If cold water is pumped into an overheating boiler, it may vaporize into steam, driving up the air pressure within the system and potentially triggering an explosion. While you wait for the boiler to shut off and cool down, consider the possible dangers of working with heating equipment and gas. It is wiser to bring in certified HVAC contractors rather than attempt to dismantle and repair the machine yourself.
Testing Your Thermostat's Connection
In some cases, the boiler is not the problem at all and a faulty thermostat is to blame. This is often the cause when your boiler never seems to shut off or your radiators are dangerously hot to the touch. Without a signal from the thermostat, the boiler will keep trying to warm up the house until it finally overheats and fails. Replacing the thermostat and calibrating the boiler properly should solve the issue, though you should have your boiler inspected for damage.
Examining the Aquastat
The aquastat is a small device that limits the water temperature within your boiler, shutting it down as necessary to maintain safe temperatures and pressure levels. Read your boiler's manufacturer's manual to find its optimal temperature range, and double check that the aquastat is at the correct settings. If the aquastat has failed due to age, on the other hand, it will need to be replaced before the boiler can be operated safely again.
Checking the Expansion Vessel
Another possible culprit in an overheating boiler is the expansion vessel, which acts as a side-chamber to accommodate surplus water. A broken expansion vessel, such as one with a stuck switch, can no longer provide pressure relief for the rest of the boiler, leading to overheating. No matter what the cause of the trouble, remember to always take the right precautions when working with a boiler. If you are at all uncertain about your knowledge or skills, keep yourself out of danger and call on the services of experienced boiler repair contractors to bring your heating system back into balance.