I have a truma ultrastore which does a odd thing, when I turn it on it lights first time but the igniter seems to keep clicking like it’s trying to start even though the boiler is lit and starts heating. I’ve given it a good blow to get rid of any dust and removing the cover seems to stop the problem. Put the cover back on and the clicking comes back and can cause the boiler to throw a red flashing light. Tried the unit on Calor gas and have now installed Gaslow system and still does it so I know it’s not a gas problem?