I installed a Ideal icos 24HE boiler today and was carrying out all the gas rates etc. I noticed in the instructions that the ideal boiler works with dynamic pressures of down to 14mb. Hows that possible as I always thought that the pressure at the meter had to be 21 +/- 2mb and the permissible drop was 1mb to the appliance so how could it ever be 14mb??? surely 18mb is the lowest
