Combi to Combi Boiler Swap by iGas Plumbing and Heating August 07, 2017 The video below is an example of the quality of work that we undertake and showcases our latest Combi Boiler Installation in Hertfordshire. In this particular job, we removed a troublesome Ideal Isar Combi Boiler and replaced it with a Baxi Platinum Combi Boiler in Welwyn Garden City. Being a Baxi Approved Boiler Installation Company we can offer a 10 Year Warranty on all Baxi Boiler Installations. We take great pride in our work and always go to great lengths to protect your home and your belongings. If you would like to learn more about a Boiler Installation or would like a free quote, please don't hesitate to contact us.