How To Bleed A Radiator

Bleeding your radiator is an important part of maintaining your heating system. It keeps your heating system clean, efficient and saves you money on your electricity bill.

How To Bleed A Radiator

  • Turn OFF central heating system
  • Locate the bleed valve – usually located at the top corner of the radiator
  • Give the valve a quarter or half turn counter clockwise
  • Water will begin to come out when water bubbles turn back clockwise
  • Turn ON the central heating system – check your radiator for efficiency

What do you need?

  • Radiator Key
  • Small Container
  • A piece of cloth

Precautions to take when bleeding your radiator

  • When you turn off your central heating system before you begin the process, take a few minutes to let the water in the heating system cool down. The water when you first turn off the central heating system can still be scalding hot; you do not want to burn your skin bleeding your radiator.
  • When you release the valve by turning counter clockwise water will begin to leak, it is important to use the cloth to catch the water coming out of the valve
  • The small container will be placed directly under the valve on the floor to collect the water the cloth could not collect
  • You will hear hissing when releasing the valve; this means your radiator has started the bleeding process
  • Check for heat distribution of your radiator to make sure the bleeding is successful after the whole process has been done.

Why do I need to bleed my radiators?

You need to bleed your radiators to prevent inefficient heating. You can tell this easy by moving your hand around the radiator and observing where the heat is being distributed.

What am I looking for?

  • The radiator is cooler at the top than at the bottom of the radiator
  • The radiator is cool all over the radiator
  • The radiator being cold when the central heating is on
  • The radiator feels cooler than the setting indicated on the thermostat of the central heating system

What is happening when I bleed my radiators?

When trapped air displaces the hot water, the radiator uses to heat your home. Bleeding the radiator fixes this problem by taking out the trapped air in your radiators and allows the free flow of hot water to reach your heating unit.

This is an excellent DIY skill to have, but if after trying this process out to fix the heat distribution of your radiator is ineffective the problem may be your central heating system as a whole. If the radiator is still cold after you bleeding, call an HVAC technician for an inspection of your central heating system.

Call One Hour Heating & Air Conditioning® of the Bay Area and one of our technicians will perform a proper central heating inspection.