How to Repressurise a Boiler via a Filling Loop

Bristol Boiler Engineer | The Bristol PlumbersAs your local Bristol Boiler Engineer the management at Reactivate Boiler and Central Heating Repairswanted to create a resource to help the fine people of Bristol with small central heating maintenance tasks. This particular one refers to the common issue of how to refill a boiler.

Some boilers & have a Standard filling loop or filling tap on pipework: This will usually look like a small silver braided hose linking two of the plumbing & heating system pipes together. It is usually on the pipework directly underneath the boiler, although it can sometimes be found under the kitchen sink or in the airing cupboard – there is no set rule about where to locate these devices so you may need to have a look around.

A filling loop will typically have a tap or a small lever of some kind on each end of the hose, although sometimes it is a screwdriver slot-type affair. With a filling loop arrangement opening both taps will refill your system, it usually refills very quickly so be careful not to operate it for too long. Very importantly you must remember to close both taps following refill and if possible remove the hose.

Bristol Boiler Engineer – Here to Help

When refilling your heating system be aware that most sealed boiler and heating systems require a cold pressure of 1 bar for correct operation, however this is dependant on the size of your heating system, the number of radiators and the height of the building. If you need assistance or advice then give one of our Bristol heating engineers a call. Always remember to turn off the fill valve(s) to avoid overpressurisation once you have the required heating system pressure.