Is No Water When Bleeding a Radiator a Bad Thing? Potentially, yes. If you don't have any water coming out of a radiator after bleeding, it means you could have something blocking the bleeder valve, the pressure is insufficient in your central
Yes, it is perfectly normal for water to escape when a radiator is bled. You'll likely notice some drips emerging when initially turning the bleed screw in an anti-clockwise direction. And water would pour out once the air was released, if the valve was to be opened fully.
This is an indication that you have debris, a blockage, or most likely, sludge, which has accumulated in the radiator. Hot water is not able to circulate because of the build-up at the bottom of the radiator. The most efficient and safest way to deal with this problem is to seek professional help.
If no water or air comes out when you bleed the radiator, then the valve could be blocked with paint. Close the inlet and outlet valve at each end of the radiator, then remove the screw from the centre of the bleed valve.
If you have recently bled your radiators, the pressure will drop slightly because you've released the trapped air in the system. This air needs to be replaced with water to get the pressure back up again.
Bad Water Pump or Thermostat
If the thermostat goes down, the system will not know when to release fluid into the radiator, and if the water pump fails, the system will not have the pressure necessary to circulate the coolant. If either of these things happens, the radiator will not work as designed.
Place a bucket or bowl under the TRV at the bottom of your radiator and loosen the TRV at the nut joint with a spanner. Open the bleed valve using the bleed key to remove any air in the system. Sludge and dirty water will begin to drain out. Then, loosen the lockshield valve and repeat.
Aside from the danger of working with a radiator that has the heating on, it's also an inefficient bleeding process. If the pump is running when you let out air, this will actually cause the system to draw in more air from elsewhere.
The Symptoms of a Clogged Radiator can be anything from the temperature gauge showing higher temps to steam billowing from under the hood of your vehicle.
An airlock in your heating system can be removed easily by bleeding the radiators. Doing this will force the airlock out of the system, so you should attempt this task on all your radiators, including the ones that are cold all the way through and cold at the top.
This issue could be caused by a faulty thermostat, an obstruction in the radiator, a fan or the water pump has malfunctioned preventing the coolant from flowing and dissipating heat as intended.
If the coolant level is dropping and there is no external leak evident, then the coolant is probably leaking internally, into the engine. If the car has recently overheated then this could have caused the head gasket to fail. If it has, it could be leaking coolant into the combustion chambers.
Can you bleed a radiator when the heating is on? No! It's very important to make sure your heating is off, and the radiators are cool before you bleed them. This is because radiators are filled with water and air, which is what escapes when you open the valve (include link to new pressure release guide page).
How long can a car last without coolant? You won't get far without coolant. After a few miles, the engine will start overheating if so, and may automatically cut off to protect internal components from heat damage. If it doesn't have this safeguard, you risk serious engine damage if you continue driving.
A quarter to half a turn should be sufficient to open the valve enough for air to escape. You will hear a hissing noise as soon as air drops out of the radiator - that's how you know you're bleeding the radiator correctly.
When bleeding a radiator, only a small amount of water should come out once all the trapped air has been released. Typically, you hear a hissing noise as the air escapes, followed by a steady stream of water.
Remove the radiator fill cap and pour the heavy-duty radiator flush into the radiator. Fill the remaining empty part of the radiator with fresh water. Place the cap back on the radiator. Start your vehicle and keep it running for almost 15 minutes, allowing the radiator flush to move through the entire cooling system.
If you don't have any water coming out of a radiator after bleeding, it means you could have something blocking the bleeder valve, the pressure is insufficient in your central heating system, or it could be something different.
It's perfectly normal for some amount of water to come out when you bleed a radiator. If a large volume of water has poured out, it's possible that you opened the valve fully. We recommend not opening it all the way.
This can actually do more harm than good. If you bleed a radiator with no trapped air inside, you risk your boiler pressure dropping too low and your whole central heating system failing - which is not what you want.
Make sure you've properly bled the entire radiator. If it's still not working, there might be a larger issue with the system, such as a faulty valve, pump, or circulation problem. It's also possible that the thermostat isn't functioning correctly.