I notice a big drop in pressure when my gas boiler fires up and I am cooking - is something wrong? it's always been like this - bothe the boiler and hob have seperate runs from near the gas meter so they're not both on teh same piece of pipe or anything.
If the gas is on low on the hob when the boiler kicks in it can put the hob out occassionally - the pressure drop seems worst when the boiler first fires up. - also the boiler is 10 or 20 years old.