Are there any downfalls to combi boilers? There are numerous benefits to a combi system. Any dissolved minerals in the water will be concentrated by the evaporation and will tend to form a. Marriednotdead: that would involve a lot of body-brushing for many dh's! All hot water storage cylinders must be fitted in-conjunction with a suitably sized unvented ... We clean your pipes, not your pocket! Baxi boilers received an overall. Are you having problems with your ac? not.