Boiler ratings
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When selecting a boiler, which output rating do you use. I am looking at a Biasi B10/3 and need about 55 MBH. How does the IRB rating work. The B10/3 is rated at 61MBH and the IRB 53MBH. I use oil.
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Replies
Jonathan, I'll bump your post so someone knowledgeable about boilers may see it.
If you cannot get a good answer here, try heatinghelp.com
some good boiler guys there
The IBR net water rating only applies if the boiler is outside of conditioned space, with an insulated wall/floor/ceiling isolating the boiler room from the space it is heating. This is to account (crudely) for the standby and distribution losses that are truly lost, and not heating the house.
An example of where it's appropriate to use the IBR if the boiler is installed in an uninsulated garage, with an insulated wall between the boiler and the house it's heating.
An example that would NOT be appropriate to use the IBR rating is when the boiler in a basement, with no insulation in the ceiling between the boiler room and the fully conditioned space above. In this case the heat lost to standby and distribution plumbing are still all inside of conditioned space, and is heating the house, not the outdoors. In these cases, use the DOE output number.
Do you have to use oil ?
Richard,
No gas available. Don't want mini-splits for a lot reasons. So oil it is.
I rarely recommend mini splits . Was just wondering if any type gas was available . What type heat emitters do you have in the home ( baseboard , panel rads , , etc )? How well constructed is the thermal envelope ?
Richard,
I have an old house (1830) with two additions. One addition is a small family room with 2x6 walls, SIP roof, over a slab and attached to a SIP bedroom suite over a full uninsulated basement. The new parts are reasonable tight and the old part is much better that it was. I heat with a high velocity air in the new construction. This runs off my oil fired hot water tank. The old part is heated with a hot air oil furnace and is now way over sized and coming to the end of its useful life. My plan is boiler, indirect hot water, and replace furnace with a air handler. It has got to be better to have one oil burner in the basement than two. I need about 55 MBH.