Loss of pressure in a boiler in a heating system is quite rare, however it does sometime happen. Taking a look at the pressure gauge is a good way of knowing that something may be wrong. Please note that if you are not good at DIY or have little confidence you should call a professional service like Vaillant Boiler Repairs London tradesmen who are skilled.Below is a brief guide to help if you ever experience this problem:Lost pressure can be the result of a leak in a pipe or even a failure in the expansion equipment that you have installed. Vaillant Boiler Repair London tradesmen are fully qualified plumbers. Having constant pressure is important and in most modern combination boilers is kept by the flow of cold water supply through a mechanism known as the ‘filling loop’. The system can be re-pressurise through this loop. Study your boiler’s manual to see whether you can re-pressurise it yourself. If you can manually pressurise:1). Find the filling loop and the pressure gauge. Make sure that the pressure gauge can be monitored while accessing the filing loop (the ideal pressure for any sealed system is 1.5bar). The loop should have a silver flexible tube with two handles, in the off position the handles will be across the pipe. Turn them slowly so they are both in line with the pipe. You should now hear the water moving through.2). Watch the pressure gauge as it rises into the green or the 1.5 bar mark. Return both the handles back to their original position.It is possible to put too much pressure into the system if you don’t watch the gauge. If this is the case, then get some help. Should it isn’t right, then call a professional.
