I have a static (holiday) caravan that is fitted with domestic central heating via a Combi Boiler. For 6 weeks a year (17 Jan - 7 Mar) all mains connections to the caravan are disconnected (water, gas & electric). I have no choice in this, it is a site rule, and is carried out by the site. I have heard that this is not good for the boiler as it is possible for the pump and fan to seize if inoperative for a long period of time? I am sure that it was a Corgi registered Heating Engineer that informed me of this, and that he also told me that. even with the boiler switched off, as long as it is connected to a power supply the fan/pump will still run at intervals to stop them from seizing? I am trying to put a case to the site that they leave the power connected to the caravans during the closed period but require confirmation that what I have outlined is correct? Any help wouild be appreciated.