Are there any downfalls to combi boilers? There's no need for a separate hot water storage cylinder or cold water feed cistern, so they take up much less room than heat-only boilers (below). Our experts are here for all of your plumbing needs as well give us a call today to find out more! Reviews completed by customers who've claimed on their boiler cover policy. Mike and i are still in love with our bathrooms — and would recommend avon plumbing without.