Measuring the temperature drop across a radiator is a key step in understanding its efficiency and is particularly important when balancing a central heating system. A significant temperature difference between the pipe where hot water enters (flow) and where cooler water leaves (return) indicates the radiator is effectively transferring heat into the room.
While you can measure the temperature drop by simply checking the flow and return pipe temperatures when the system is running normally, the provided reference describes a specific method used during the process of balancing radiators. This method involves adjusting the return valve to achieve a target temperature difference, commonly 12°C, across the radiator.
Here's how to measure (or more accurately, establish and verify) the temperature drop using the balancing method described:
Method for Measuring Temperature Drop During Radiator Balancing
This method involves a specific procedure focusing on adjusting the return valve to achieve a desired temperature difference.
- Shut the Return Valve Completely: Begin by ensuring the radiator is hot. Fully close the valve on the return pipe side of the radiator.
- Measure Pipe Temperatures: Use a reliable contact thermometer (like a pipe clamp thermometer) to measure the temperature of the pipes near both the Return Valve and the Flow Valve. You'll need to take readings simultaneously or in quick succession.
- Slowly Open the Return Valve: Gradually open the return valve, little by little.
- Achieve the Target Temperature Difference: As you open the valve, continue measuring the temperatures at the two points. The goal is to slowly open the valve until the temperature difference between the flow and return pipes reaches 12°C. You might need to make small adjustments to the valve opening to get the reading exactly right.
This process ensures that each radiator is receiving the correct amount of hot water flow to achieve an optimal temperature drop, contributing to a more balanced and efficient heating system.
Practical Tips:
- Ensure your heating system is fully heated and has been running for a while before starting.
- Use a consistent method and location for measuring temperature on each pipe.
- Be patient, as slight adjustments to the valve can have a noticeable effect on the temperature readings.
