Hi. BG under their homecare plan came out to fit a new expansion vessel. I can see that we are still losing pressure albiet a tiny tiny amount compared to last time. The copper pipe outside is wet....probably the odd drip every now and again. I'm beginning to think that it could be the PRV valve that might not be seated correctly hence a small leak from the copper pipe outside. Before the expansion vessel was fitted BG said it only needed a Schrader valve as it was leaking but when he fitted the new valve he bust the vessel. I go on my hols in a week so I'll call them back in a few weeks to come back and have a look. Just wanted your thoughts as we've had 2 BG engineers so far. First one bust the vessel and second one fitted the new vessel and put on a new pressure gauge. The pressure is dropping by one little line per week. Thanks in advance.