Potterton PowerMax HE A15 Error low pressure?

My potterton powermax he boiler has an error code A15 (low pressure) and the boiler won't light. I am cold! Have tried resetting it/turning it off and on etc etc but still not lighting. The pressure on it has been low since I moved in recently (never above 1 bar) but it hasn't gone out before. Any help/suggestions? I can't report it to my landlord till Monday :(