Sizing boilers & replacement heatsystems
I’ve run into a problem that I’m sure is not unique. I am restoring a 150 year old house that is now a duplex- and has been for a hundred years or so.
The next problem on the “to-do” list is replacing one of the heating systems.
The apartment is four rooms and I would like to put heat in all 4 rooms plus the bathroom. It currently only has a hot air furnace in the floor between the kitchen and the living room- leaving the upstairs quite cold in New England winters. The heat loss calculation requires 32,000 BTU. The smallest Weil McLain boiler is rated at 74,000 BTU (with a domestic hot water zone)- massively oversized and therefore, inefficient.
I would like to use antique steam radiators for the hot water system (more keeping with the house-style and more tenant-proof). Gas is not an option- so it would be an oil fired boiler. Has anyone found a small boiler, or an ingenious way of creating central heat for a small house? I was even thinking of using a point-of-use hot water heater for the boiler, but don’t know much about them.
Replies
If your intention is to use hydronic heat (hot water or steam) in this building then I recommend that you take a look at http://www.heatinghelp.com.
Note that steam systems use really large-seeming boilers (much larger than hot air system (typical rule of thumb) estimates would suggest), but they operate so much less often that they can be more efficient.
Any hydronic design must be carefully balanced for best efficiency - more planning is called for than when running simple forced air type heat, that's why forced air is so common, its easy and cheap. Hot water heat will use radiators to good effect and can be very efficient.
Thanks for the website heatinghelp.com. Have posted the question out there too. Am hoping someone has a great idea for a 32,000 BTU boiler. Yes, I'd much rather put in a hot water system than an air system. Thanks!
There are smaller boilers available, I know I just put one in. I did heat loss calcs. and came up a lot less than heating contractors. So I went with my own and installed a 60000 BTU Weil-Mclean. This winter has been very cold and so far no complaints from the wife.