faulty water pressure system on Vaillant boiler?....

[kebabboy]

Had a Vaillant ecotec pro24 boiler installed two days ago.
I'm just a bit worried about the water pressure of the system.
When the installers left, the pressure was at 1.5 - but it quickly dropped to 0.8 when cold. The manual states that the pressure gauge must be between 1.0 and 2.0 bar, otherwise I need to fill up the system blah blah blah.
I know how to do this, but should the water pressure have dropped like this?
What should the pressure be on the boiler when it's cold?
I'll keep a watch on it over the next few days but I'd appreciate and be grateful for some advice.
My heating is fine (nice hot rads) and the water pressure out of the taps seems fine too.
Thanks

 

[Burnerman]

To be fair, just give the system a little while to settle down...inevitably there will have been some air let into the system, which should find its way out of the automatic air vent in a day or so. Keep the pressure topped up, bleed the rads if you feel that its necessary and see what its like after a week.
John