We clean your pipes, not your pocket! Combi can you even still get traditional boilers? When i think of the extra cost i could have ended up paying british gas, not only for the boiler but for unnecessary boiler cover, my blood really starts to boil. You saw the fellow who let you in at the school gates, plumber? Non ionic surfactants, contains, preservatives (methylisothiazolinone, benzisothizolinone), enzymes,.