heatingradiatorwater-circulating-heating
Almost all of the radiators (forced water) in my house heat up fine. However, a single radiator needs regular bleeding (~1/day) in order to heat. Note, this radiator is not at the highest point in the house (it's a split level; I'd say it's around 3/4 of the way up), and radiators higher up are plenty hot.
Also, there no obvious water/corrosion stains around this radiator.
What might be causing this problem, and how do I fix it?
No need to panic, it's probably pretty simple. It sounds like your system is full of air and just needs to be bled. You've probably bled all the pressure out of the system, so you'll need to re-pressurize it, then bleed the radiators again, then pressurize again, bleed again, until all the air is gone.
Look at your boiler, there should be a pressure gauge on it. It should have a green arc, and maybe a yellow ark before having a red ark. Most likely green will go up to 2 bar(29 psi). Right now the needle is probably on the low end of the scale.
You'll need to find your pressurization valve, and open it until you get some pressure. The pressurization valve is between your home's water supply and the boiler, all you need to do is open it until you get about 1.2 to 1.5 bar and then close it. If you cannot find the valve see if you can find the manual, or just ask a neighbor who seems handy. It's very simple and you shouldn't need to pay anyone to do it.
Be careful not to over-pressurize the system, turn off the pressurization valve before the needle goes into the red.
The pipes should look like this:
There should be an unrestricted flow around the system.
Each radiator should be connected to both the flow (red) pipe and return (blue) pipe. The turnable value (or better still thermostatic valve) should be on the input to each radiator. There should be a simple on/off valve on the outlet which is normally set to fully open.
Best Answer
When you do your daily bleed of this radiator if you don't actually get air coming out, just water. You don't have an air problem, you have a water flow problem.
If your system a diverter-tee system (a "one-pipe" system), check to make sure that the tees that feed this radiator are installed the same way as the tees that feed your working radiators. The diverter tee for this radiator should be on the return side, and the stripe (or other indicator of orientation) should be between the branches. An incorrectly installed tee could cause the exact problem you're describing.