Major boiler issues. Banging and shaking the house when heating the water. Two engineers separate ocassions still not fixed despite having paid over £800. High levels of CO identified second time that should have been checked by first engineer. Sludge that needed cleaning, again should have been identified before. Emailed with all details of complaint, received a call 3 days later saying they are 'looking into it' but lady going on holiday for 2 weeks and would continue to 'look into it' on her return. Disgusted and disappointed as the charges are high so I assumed the service would match. I have taken it further