Here's a closeup of the boiler. As I've said before, it's about the size of a dishwasher. The black protrusion is the fan that blows the flame across the heat coils. The hot water outlet is at top-left (hard to see because it's black against the black plywood), and it looks as if the cold water return is the unconnected pipe at bottom-left. The whole thing is sitting on 2" thick PINK pavers.