Can anyone point me to a link where I can find a decent, relatively easy to use heat-loss calculator?
Long story short, last weekend storm here in New England resulted in us losing power overnight and flooded the basement. Woke up to 2 feet of water in the basement. Fortunately, not finished, but we lost the washer/dryer and the furnace -- water was almost up to the bottom of the honeywell controller, but effectively the burner, all the lower electronics, and interior chamber were all flooded.
Boiler was a 3-section Burnham installed about 1991, about 100KBTU from what I have been able to ascertain.
Since then, I have done major work on the house, added about 700 sq ft of living space on the 1st floor and added a dormer on the 2nd floor which added quite a bit of space as well. Also, the boiler was originally installed as part of a hydro-air system, which I have subsequently converted to baseboard FHW and ripped out all the duct work.
This is a 300 y/o farmhouse which is fairly loose, has some but less-than-standard insulation in many areas (as well as some areas with zero insulation), and single-pane glass windows with a storm window for most windows. I've never done a FLIR probe of the house, but I'm probably on safe ground to say it flares up like a christmas tree.
I mentioned this to the oil guy who came out to look at the damage, and asked if they could do a proper heat-loss calculation to ensure the replacement boiler is adequate, as I think I probably need a larger boiler. He said he would.
Got my quote in the mail Friday, and they're proposing another 3-section Weil-Mcclane WGO in its place.
So, I think what they did is simply do what most furnace people do -- "oh, that's a 100k btu boiler, so we'll just quote one the same size".
Well, I heat mainly with wood in the winter and leave the house at 50 on the thermostat, so the boiler almost never does any 'hard work' since my Jotul F55 is carrying most of the heating load in the main living space, and those zones I do not use much in the winter are maintained at 50 by the boiler. I've never attempted to keep the whole house at 70 degrees using the boiler -- not sure if it could.
I found a Slant-Fin heat-loss calculator on my phone, but its tough to use and I had to make some educated guesses as to what figures I should use. For instance I have no idea how to figure out how many BTUs my basement needs, I do have 1 zone of heat down there but much of the "basement" is open to crawlspaces where is there is no heat other than what comes off the boiler and the 1 zone I have down there (which is mainly to keep the well tank and associated equipment from freezing in the winter.) Then I had to guess about other things, like how to account for sections of the house which are built over a concrete slab which is 12" above grade, etc.
I ended up, after all was said and done, with an estimate of 150kBTU (with a 61 degree temperature differential, Boston's ASHRAE 99% # is 9 degrees, and I used an indoor temp of 70) but, like I indicated, the software isn't exactly the easiest to use and some of the options probably make sense to an HVAC guy but not to me. That would put me in a 5-section boiler not a 3 section.
Since I'm replacing the boiler, I want to make sure I replace it with one that can handle the load should the wood stove not be in use. Or, am I off-base in that respect?
I have a call in to the company to speak to the person who quoted the boiler... and I want to protect myself from the "yeah we ran the numbers and that's what we came up with"... An educated consumer is, after all, a smart consumer.
On the up-side, the Jotul, our only source of heat now, is still cranking along, keeping the main section of the house livable (and the outskirts tolerable in the high 40's. Outside temps in the 40's haven't hurt, either. Going to end up burning a full 3 cord this year, I think.
Long story short, last weekend storm here in New England resulted in us losing power overnight and flooded the basement. Woke up to 2 feet of water in the basement. Fortunately, not finished, but we lost the washer/dryer and the furnace -- water was almost up to the bottom of the honeywell controller, but effectively the burner, all the lower electronics, and interior chamber were all flooded.
Boiler was a 3-section Burnham installed about 1991, about 100KBTU from what I have been able to ascertain.
Since then, I have done major work on the house, added about 700 sq ft of living space on the 1st floor and added a dormer on the 2nd floor which added quite a bit of space as well. Also, the boiler was originally installed as part of a hydro-air system, which I have subsequently converted to baseboard FHW and ripped out all the duct work.
This is a 300 y/o farmhouse which is fairly loose, has some but less-than-standard insulation in many areas (as well as some areas with zero insulation), and single-pane glass windows with a storm window for most windows. I've never done a FLIR probe of the house, but I'm probably on safe ground to say it flares up like a christmas tree.
I mentioned this to the oil guy who came out to look at the damage, and asked if they could do a proper heat-loss calculation to ensure the replacement boiler is adequate, as I think I probably need a larger boiler. He said he would.
Got my quote in the mail Friday, and they're proposing another 3-section Weil-Mcclane WGO in its place.
So, I think what they did is simply do what most furnace people do -- "oh, that's a 100k btu boiler, so we'll just quote one the same size".
Well, I heat mainly with wood in the winter and leave the house at 50 on the thermostat, so the boiler almost never does any 'hard work' since my Jotul F55 is carrying most of the heating load in the main living space, and those zones I do not use much in the winter are maintained at 50 by the boiler. I've never attempted to keep the whole house at 70 degrees using the boiler -- not sure if it could.
I found a Slant-Fin heat-loss calculator on my phone, but its tough to use and I had to make some educated guesses as to what figures I should use. For instance I have no idea how to figure out how many BTUs my basement needs, I do have 1 zone of heat down there but much of the "basement" is open to crawlspaces where is there is no heat other than what comes off the boiler and the 1 zone I have down there (which is mainly to keep the well tank and associated equipment from freezing in the winter.) Then I had to guess about other things, like how to account for sections of the house which are built over a concrete slab which is 12" above grade, etc.
I ended up, after all was said and done, with an estimate of 150kBTU (with a 61 degree temperature differential, Boston's ASHRAE 99% # is 9 degrees, and I used an indoor temp of 70) but, like I indicated, the software isn't exactly the easiest to use and some of the options probably make sense to an HVAC guy but not to me. That would put me in a 5-section boiler not a 3 section.
Since I'm replacing the boiler, I want to make sure I replace it with one that can handle the load should the wood stove not be in use. Or, am I off-base in that respect?
I have a call in to the company to speak to the person who quoted the boiler... and I want to protect myself from the "yeah we ran the numbers and that's what we came up with"... An educated consumer is, after all, a smart consumer.
On the up-side, the Jotul, our only source of heat now, is still cranking along, keeping the main section of the house livable (and the outskirts tolerable in the high 40's. Outside temps in the 40's haven't hurt, either. Going to end up burning a full 3 cord this year, I think.
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