Finish Here
After entering information in one or more sections below, click Calculate to see a list of boiler recommendations. Enter a negative BTU adjustment if you have a supplemental heat source that will also be incorporated.
DISCLAIMER
Alternate Heating Systems makes no guarantee, either express or implied, of the fitness of this BTU Calculator for any purpose. It is provided as a means to obtain a general BTU heating requirement number. Your individual heating situation may require an on-site analysis of your heating requirements, particularly if the structure being heated is large and/or irregularly shaped. In using this application, you agree to indemnify and hold Alternate Heating Systems harmless from any and all actual or perceived losses on your part, either monetary or material, from your use or misuse of this application. Your use of this application constitutes your acceptance of this Agreement.
All units are as follows:
- Temperature - degrees Fahrenheit
- Length, width, height, depth - feet
- Area - square feet
- Time - hours
- BTU Adjustment - BTU's / hour
Background
This calculator uses the information entered into one or more of the sections below to calculate a BTU/hr requirement and then return the smallest boiler(s) from each product line (if any) that meets the BTU requirement.
Instructions
To use this calculator, enter values into any or all sections. The "Calculate" button will become available when all data has been entered for a particular scenario. If the BTU requirement exceeds the largest boiler in a particular product line, an 'Insufficient' message is displayed. Click on a boiler in the list of recommended boilers for information about that boiler line.
Refreshing the page will clear the calculated results.
BTU Adjustment / Supplemental Boiler
If you have an existing boiler and you want to supplement your boiler with an Alternate Heating Systems boiler, then enter into the BTU Adjustment field a NEGATIVE number corresponding to the BTU output of your existing boiler to find the recommended Alternate Heating Systems boilers that would supplement your system.
Specifying Snow Depth:
The average depth of surface is the depth of snow in feet, so a decimal value must be entered in this field if inches are desired as part of the depth.
Residential/Commercial
The Res/Comm column shows the Residential and/or Commercial designation for each boiler.
ASSUMPTIONS MADE IN THIS APPLICATION:
BUILDING SECTION:
All multi-story houses have full residential spaces above the ground floor.
The analysis is based on a wind speed of 15 mph.
This component assumes, conservatively, that all houses will be over a non-insulated, vented, and unheated crawlspace. This helps ensure that the calculated BTU value is high enough.
SWIMMING POOL SECTION:
The calculator is designed for in-ground swimming pools only.
The calculator is designed to allow two types of swimming pool heating calculations: heating from a much lower temperature to a desired temperature over a period of time; and constant temperature maintenance heating on a per-hour basis. To calculate the BTU requirement for temperature maintenance heating, enter one (1) hour as the time to heat and enter the desired water temperature as both the Initial and Final water temperatures (i.e., you wish to maintain the same temperature at all times). If, in the case of maintenance heating, you are willing to allow the temperature to fluctuate somewhat, then you could adjust the initial temperature down by the amount that you are willing to allow the temperature to fluctuate while still using one (1) hour as the time to heat.
Ambient temperature refers to the temperature of the air above the water. This variable, of course, can fluctuate, and you will have to make your own assumptions and calculate your own average for this variable. This value will be easier to determine for an indoor pool, of course, than for an outdoor pool.