System Cleaning

System Effects and Flushing Recommendations

Power flushing is the most effective method of cleansing a central heating system. A power flush is recommended as the optimum method of restoring system efficiency, particularly on an existing system. A power flush combined with an effective cleanser and administered correctly will remove up to 95% of system sludge and scale.

The benefits of system flushing are:

• Improved system efficiency 
• Maintains boiler efficiency (1mm thickness of scale / sediment will reduce efficiency by approx. 10%)
• Reduced fuel costs (boilers will consume up to 25% more fuel if system is unclean)
• Reduced greenhouse gas emissions 
• Reduced maintenance costs 
• Reduced potential for boiler noise 
• Extends system life  

For an existing system:

1. Fully drain off the system from all available drain off points.

For new system start here:

1. Fill the system with cold water and check for leaks. Fully drain off the system from all available points
2. Introduce correct amount of cleanser into the system (dilution depends on system volume and cleanser)
3. Introduce correct amount of cleanser into the system (dilution depends on system volume and cleanser)
4. Ensure all gate valves and TRV’s are fully open or TRVheads removed
5. Turn ON the boiler and bring the system up to maximum heating temperature (refer to manufacturer’s instruction)
6. Once up to temperature, run the system for at least one hour allowing the cleanser to fully circulate
7. After specified time, empty the system thoroughly, using all drain off points and ensuring all low lying pipe work is fully drained. Open all bleed valves to ensure the system has been fully emptied
8. Refill the system
9. Turn the boiler ON and circulate for at least 10 minutes or until the radiators are warm. Bleed the air from the radiators and pump to fully ensure all parts of the system are filled with water
10. Fully drain the system again using all drain points and ensuring all low lying pipe work is fully drained. Open all bleed valves to ensure the system has been fully emptied
11. At this point, test water quality from system with a TDS meter, shake test (water should not produce a stable foam when agitated in a bottle) or alternatively drain and refill until water is clear to the eye and then drain and refill twice more
12. If water quality is not in tolerance, a reading must be within 10% of the tap water, repeat steps 8 to 12
13. Introduce an inhibitor into the system (dilution depending on the system volume and inhibitor)
14. Refill the system
15. Bleed the air from the radiators to fully ensure all parts of the system are filled with water

Remember:
“Good system flushing is always worth the time. It has been shown that there is a direct correlation between how well a system has been cleaned and treated, and the reliability and efficiency of the whole system.” Dr. Carl Jasper AQUADEMIC