Here`s the situation. I purchased my house eight years ago. It was a handy man special to say the least. I replaced virtually everything including the boiler, although at the time I hadnt considered enlarging the house. I am in the process of planning an addition that will almost double the size of the home. I am trying to determine the minimum BTUs required to heat entire house. I currently have a gas fired hot water baseboard system and plan to add to it. What is the proper way to determine the boiler size neccesary? Thanks in advance for any help!
P.S. Water heater is a seperate unit.
J. D. Reynolds
Home Improvements
“DO IT RIGHT, DO IT ONCE”
Replies
Not an easy topic (IE lots of variables). This might help for a start.
http://heatinghelp.com/
bobl Volo Non Voleo Joe's cheat sheet
Edited 9/5/2002 4:23:14 PM ET by bobl
The size of the heat system is dependent on the heat loss through the walls, windows, roof, floor etc. So the less heat loss the smaller the boiler needed. Maybe you could install infloor heating. As shown in the last few years gas can jump in price and your thick insulation will save you even more! Payback is often mentioned as a "prevention" to building/installing the most efficient energy home/equipment but I feel I don't want to burn it up because "payback" is 30 years.
"What is the proper way to determine the boiler size neccesary?"
JD,
The first task in determining the required size of any heating (or cooling) equipment is to perform a heat loss/gain calculation.
You have to know: the construction of the walls, ceiling and foundation, including insulation; the type of windows; the dimensions of everything; and the design conditions for your locale.
Armed with this information, you can determine the "U" values for walls, ceilings, windows and perimeter (foundation losses). Crunch the numbers and add it up. Add in some losses for air infiltration and you have your maximum heat loss.
Having done this more than a few times, the heat losses in houses can range from 6 btuh/sq ft to 45 btuh/sq ft. Anyone who can size you boiler witout doing a calculation is either an omnipotent or an idiot.
Edited 9/6/2002 8:09:13 AM ET by Tim
Geez, I always thought they sized your boiler (or furnace) by looking in the back of the shop and picking whatever had been sitting there the longest.
Good judgement comes from experience, and a lotta that comes from bad judgement
Doc
All yer methods suck.
Here's how...
Stand across the street and hold your arm out. However many fingers it takes to block the house from view is how many hundred thousand BTU's it takes.
LOL
Oh, Great Warrior with Soggy Noggin,
You have again learned me something new! Now I can stop wasting all that time with paper. So how do you do coolin' ?
Tim