HW no CH Gloworm

Hello there - we have just moved into new house which has been vacant for at least 5 months. we have a gloworm wall mounted boiler c. 1998. Hot water works fine, but central heating dosent come on and the pipe for the water for heating is not hot. Yesterday the light for the heating came on briefly when i turned on a tap in the bathroom - but then went out again. No thermostat in sight. Also, when we were trying to fix it we increased the pressure by accident from 0.9 to just under 3.0..... Is it safe to have the boiler on at all because of increased pressure and how do I get the heating to work? Have NO technical knowledge whatsoever, so please make answers easy to understand! Thanks guys.

First find a drain point on a pipe somewhere, hopefully. They usually have a small square bit on top which you turn. Let water out to get the pressure down to about 1 bar.

Which Glowie is it?

Hello - I've bled all the radiators and the heating is working now (thankfully!). I'm just a bit worried about the pressure - its a Glow worm Compact 100e - fanned flue combo boiler. Its says in the manual that the pressure should be a minimum of 0.7, but it dosent say what the max should be... when heating & hot water not in use the pressure is at about 1.4, but when CH & HW on, it quickly rises to around 3.0 - is this ok?
Thanks for you help

No; it means the expansion vessel need attention.

First check if the vessel has water or air by depressing the schroeder valve on the top.

if water then you need a new vessel, if air it needs recharging so come back with your findings

thanks will report back later on today.