When the boiler is off the pressure is about 1.3bar. When the boiler comes on the pressure drops to 0.8bar. It should be the other way around - 1.5bar on and 1bar off.
The boiler and central heating all work ok but this problem needs resolving.
Any ideas apart from refilling the system?

Anthony Fish, December 2009

what mean E1 and showes number 68

barbara, January 2010

I am not sure but when pump start it is create negetive pressure to the gauge depends where tube is connected so pressure drop, may be not enough return water is feeding to the pump so this may happen.

Mr K, December 2009