I have ariston euro combi boiler and i get some time warm water or cold water and not hot constant water coming out from the boiler, even when central heating is on . some days hot water will flow for few minutes and then cold.

please advice what can i do

lal, November 2010

I have the same problem with my Ariston. So far, I have discovered that low water pressure in the heating system, along with trapped air in the radiators, are things to be fixed. The water pressure may be low (see the water pressure gauge on the boiler), should be 1 to 1.5 bar on the A/23 model. To increase the water pressure, the water must be topped-up at the boiler. The installers do this with a temporary flexible hose but I have no idea how this is actually done.

Chris Ward, November 2010