Before you replace the boiler pressure relief valve on your home heating system, make sure that you have eliminated any other potential causes for why your pressure relief valve is not working. The best way to accomplish this is to call a trained service technician to your home to diagnose the issue and repair it properly. Keep in mind that just because water is coming from the pressure relief valve, doesn’t mean that the valve isn’t acting appropriately.
For instance, if the pressure in your system is too high because of a bad expansion tank, the pressure relief valve will open to release pressure from the system. This doesn’t mean that the pressure relief valve is broken; it means that the pressure relief valve did exactly what it was supposed to do to protect your boiler and your safety. Other causes of high pressure in your system can come from a faulty fill valve or a leaking coil. Unless you are an expert in boiler repair, you should have a service technician check the system thoroughly.
Even if the problem does turn out to be an old or defective pressure relief valve, boiler pressure relief valve replacement is not as easy as plunging a backed up toilet. First of all, you will need to purchase the proper replacement part at your local hardware store. Make sure that the valve you purchase will work properly according to the specifications of your boiler.
Secondly, you will need to take precautions to ensure your safety and prevent any additional damage to your boiler. This includes, but is not limited to, turning off the power and water to the boiler and draining the system until there is no pressure in the boiler. Then, and only then, should you attempt any work on your boiler yourself.