How to Repair Steam Heat Radiator Problems

Lead Image for How to Repair Steam Heat Radiator Problems
  • 2 hours
  • Intermediate
  • 20-60
What You'll Need
Pipe wrench
Channel lock pliers
Plumber's pipe dope
Small metal wire or sewing needle
New inlet valve
Wire brush

If you use a steam heat radiator to warm your home, there could come a time that the unit does not function the way it should and will need to be repaired. You could hire a professional to make repairs on your steam radiator; however, there are several common types of repairs that you can do yourself and save a lot of money in the process. Many steam heat radiator repairs are easier than you might think, and this handy how-to guide will walk you through the most common ones. Let's get started.

When a Single Radiator Won't Heat Up

Step 1 - Bleed the Hot Water Radiator

If you have a single radiator that's not producing heat, while the others are working fine, you may need to simply bleed the pressure from the faulty radiator. To do this, look for a small valve near the top of the radiator. Then, take a radiator key, small socket or flat head screwdriver and turned the valve counterclockwise. This will release trapped air and cause hot water to flow out of the valve. Catch the hot water with a small plastic container.

Step 2 - Clean Out the Air Vent Hole

If bleeding the pressure from the radiator doesn't help, try cleaning out the air vent hole on the side of the radiator. Sometimes, the hole gets plugged or even painted over. So, look for a small hole about halfway down the side of the radiator and use a small piece of metal wire or even a sewing needle to clean it out.

Silencing Noisy Radiators

Step 1 - Check the Main Steam Valve

If your a steam radiator is making banging noises, check the main valve on the radiator. The valve needs to be all the way open or all the way closed. If the valve is somewhere in the middle, it will usually produce inconsistent pressure, which will cause the banging noises.

Step 2 - Check Placement of Radiator

Over time, hot steam radiators can cause some types of flooring to warp. So, check to make sure that your radiator is flat and level. If it's not, you can use small wooden shims to level the radiator, which will help stop banging noises in many cases.

Step 3 - Replace the Steam Valve

If the above two steps don't help with your noisy radiator, you probably need to replace the main steam valve. Before you do this, you need to shut off the boiler and also make sure that there is no pressure in the radiator can. Then, simply remove the valve and install a new one. Make sure to use pipe dope on the fittings when installing the new valve.

No Heat at All

Step 1 - Check Breaker for Boiler

If your steam radiators are producing no heat, you should first check the breaker at the main service panel for your home. Make sure that the switch is set to the 'on' position.

Step 2 - Check Pilot Light

Check the pilot light in your boiler. If the pilot light is out, you'll need to light it again. Refer to the instruction manual for your steam boiler for information on how to light the pilot light.

Step 3 - Adjust Boiler Water Pressure

Your steam boiler will need to have water pressure of about 12 to 15 PSI. Therefore, adjust the pressure valve on the boiler until it is in this range. Once the boiler is producing the correct amount of pressure, the radiators should begin producing heat again.

If all else fails, you can rethink the situation from scratch and replace your whole radiator.