You might find the heat/cold cycles could draw moisture into your hubs or bottom bracket. The air inside the hub gets warm in the boiler room and expands. Then you take it outside in the cold on a wet day and as the air in the hub contracts, it sucks in water from outside the hub, through the bearings. This eventually washes out the grease.
I've read somewhere about this happening, and I was thinking it was on sheldonbrown.com, but I can't find it now. The solution suggested was to put the bike someplace cold and dry for a little while before riding it in the wet, so it will cool down and suck in cold dry air, rather that cold wet water.