If you have multiple radiators in your house and all of them are cold or lukewarm, you probably have a larger issue with your heating system - your water heater may be malfunctioning or you may have a buildup of sludge or sediment somewhere in your heating system[2] X Research source (see: How to Flush a Water Heater. ) If your radiator problem is accompanied by an accumulation of water beneath the radiator, your radiator has a leak. Try turning your heat off, then tightening the nut(s) on your radiator’s inlet valve. If this doesn’t fix the problem, the nut may be corroded - replace them or call a professional. If the radiators on the upper floors of your house aren’t heating up but the radiators on the lower floors are, your heating system may not be operating at a high enough pressure to get hot water to the top floors of your house. [3] X Research source
Some modern radiators are equipped with valves that are designed to be turned with a simple flathead screwdriver. [5] X Research source Before proceeding, make sure you have a radiator key, a screwdriver, a wrench or some combination of implements so that you’ll be able to open the valves on every radiator in your house. When bleeding one radiator, it’s best to bleed every one in a house.
Opening the bleed valve allows trapped cold air to escape, which is replaced with liquid from your heating system via the pipes connected to your heating system.
For residential heating purposes, a pressure level of around 12-15 psi should suffice. The higher the pressure, the greater the height the height that heat from your system will be able to travel. Especially short or tall houses may require lesser or greater boiler pressure, respectively. [10] X Research source If your boiler has an automatic fill system, your boiler should maintain a pressure reading of about 12-15 psi without any work on your part. If not, add water manually - open the boiler’s water feed valve until the pressure gauge reads about 12-15 psi.
Abnormally high temperature readings on your dashboard temperature meter. [11] X Expert Source Duston MaynesAutomotive Repair Specialist Expert Interview. 10 June 2021. Fluid boiling out of your radiator. Odd smells from your engine, especially sweet smells (caused by antifreeze leaking and/or burning up. ) A low coolant light when you first start the vehicle. [12] X Expert Source Duston MaynesAutomotive Repair Specialist Expert Interview. 10 June 2021. Additionally, it can be a good idea to bleed your radiator after performing maintenance or part replacement on your cooling system. Air can be introduced to the system during maintenance work - keep an eye on your temperature gauge after modifying your cooling system in any way.
To bleed a car’s radiator via a bleeder valve, simply loosen it until you hear the hissing sound of air escaping. Use a cloth to catch any sputtering coolant, then re-tighten the valve when the valve releases a steady stream of coolant. [14] X Expert Source Duston MaynesAutomotive Repair Specialist Expert Interview. 10 June 2021. Some cars don’t have special bleeder valves. Don’t worry - it’s still possible to bleed these cars’ radiators via other processes (see below. ) Be sure the car is cool when you do this—don’t try to get the air of of a car that’s still hot. [15] X Expert Source Duston MaynesAutomotive Repair Specialist Expert Interview. 10 June 2021.
In certain special car varieties, the radiator may not be located at the front of the car - consult your car’s owner’s manual if you’re not sure.
Allow the engine to cool completely. Place a drainage pan under your radiator’s drain valve to collect old coolant. Add water to the car’s radiator until it’s full, then allow it to drain out of the drain valve under the car. Close the drain valve and add fresh coolant, generally a 50/50 mix of antifreeze and distilled water (not tap water, which can form mineral deposits. ) Do not overfill the coolant when you do this. [19] X Expert Source Duston MaynesAutomotive Repair Specialist Expert Interview. 10 June 2021. Bleed your radiator again to eliminate any air introduced during the flush and fill.
