More details, what boiler, make and model, does it have a circular pressure gauge on it, if it does wwhat does the needle, (Black) point too? is it a combi - or do you have a small header tank in loft.
Dave
May 2010
Triangle usually means there is a fault on the pump or low water pressure your boiler must be baxi system or potterton system? they are main probs but read manual for your type of boiler