I had appliance guys over to re-do my dryer vent and they were in and out got the problem solved quickly and very clean! C&i boiler would like to welcome the newest members of our team. Keep reading to find out the full results of our investigation and to download our free boiler servicing checklist. Domestic and commercial work undertaken. Most blockages are caused by a simple build up of waste or debris in the drainage pipes our standard unblock service is.