Heatrae sadia Electromax boiler help

[phil1892]

I have a Heatrae sadia Electromax boiler and when the heating is on it works fine for a while then a demand overheat alarm comes on. The pressure is constantly above 3 bar, when I turn the red release valve the pressure reduces temporarily and then goes back. How do I constantly keep the pressure down? So the heating stays on.

 

[stevetheplumber]

I have a Heatrae sadia Electromax boiler and when the heating is on it works fine for a while then a demand overheat alarm comes on. The pressure is constantly above 3 bar, when I turn the red release valve the pressure reduces temporarily and then goes back. How do I constantly keep the pressure down? So the heating stays on.

i know nothing about this model of boiler but generally if the preasure keeps creeping up the filling loop is probaly either not turned of properly or it letting by try removing the filling loop see what happens on most systems this is either under the boiler or in the airing cupboard usually near to the guage

 

[Puddle]

As steve says,filling loop is at the bottom,front of unit ,I believe ,black valve attached to a flexible chrome braided hose,the black handle wants to be across the valve fitting to be in fully off position,pressure to be around 1/1.5 bar and hopefully will hold ,if drops,probably red toped pressure release valve may need professional attention,if it has been in this condition for a while,you may have a scale build up problem