Bleeding a radiator with a thermostat involves a straightforward process of releasing trapped air, ensuring optimal heating performance. Here's a step-by-step guide on how to do it:
Bleeding Radiators with Thermostatic Valves
It's important to note that the presence of a thermostat (also called a thermostatic radiator valve or TRV) on a radiator does not change the fundamental process of bleeding it. The thermostat controls the flow of hot water into the radiator based on the desired temperature, but the bleeding process is about releasing trapped air within the radiator.
Step-by-Step Guide
| Step | Action | Description |
|---|---|---|
| 1 | Prepare the area. | Place old towels or cloths around the radiator's bleed valve and below the radiator to catch any water that may leak out. |
| 2 | Allow the radiator to cool down. | Ensure that the radiator is not hot. Bleeding a hot radiator can be dangerous due to potential steam release. Wait for it to cool sufficiently before proceeding. |
| 3 | Open up the thermostatic radiator valve. | Turn the TRV to its highest setting. This ensures that the valve is fully open and allows water to flow when the system is refilled, not impacting the bleeding process itself. |
| 4 | Open up the bleed vent. | Using a radiator bleed key, carefully turn the bleed valve (located on the side of the radiator near the top) counter-clockwise. You should hear a hissing sound as air escapes. |
| 5 | Close the vent and repeat. | Once water starts to come out steadily instead of air, close the bleed vent by turning the key clockwise. Repeat for any other radiators needing to be bled. |
| 6 | Check the boiler pressure. | After bleeding all radiators, check your boiler pressure gauge to ensure the pressure is within the normal operating range. Adjust if necessary. |
Essential Tips
- Bleed from bottom to top: Begin bleeding radiators on the lowest floor and work your way up.
- Keep a cloth handy: Have cloths readily available to wipe up any excess water or drips.
- Don't over-tighten the bleed valve: You only need to gently tighten it to close the valve. Over-tightening could damage it.
- Monitor pressure: Keep an eye on your boiler's pressure gauge and top up the system with water if it falls too low after bleeding.
Why Bleed Radiators?
Radiators can accumulate air pockets over time, which hinder the flow of hot water and reduce heating efficiency. Bleeding releases this trapped air, allowing the radiator to heat up properly and efficiently. Signs that a radiator may need bleeding include:
- Radiator is cold at the top but hot at the bottom
- Unusual gurgling or hissing sounds from the radiator
- Uneven heat distribution
Bleeding your radiators regularly, ideally at least once a year or whenever you notice these signs, can help keep your heating system running efficiently, and that includes radiators equipped with TRVs. It doesn't change the basic need for the process, or how to perform it.
