Oversizing a boiler or any other heat source is an all-too-common mistake. The logic behind it makes sense: after all, you will never get too cold if your heat source is more powerful than it needs to be. Plus, using rule-of-thumb methods saves the time needed to complete a full heat-loss assessment and get a BTU-load requirement. Simply basing the size of new equipment on the ratings of existing equipment may not give accurate figures either. The previous heat source may have been improperly sized, and changes may have been made to the structure since its installation.
Unfortunately there are some negative consequences that can result from selecting a heat source that is too large. For one, more powerful boilers cost more money. They will be louder and less efficient than properly-sized equipment. Fuel bills will be unnecessarily high, breakdowns will be more likely, and wide temperature swings could result from too much heat being created. Installing a boiler that is the right size for your particular home lets you avoid these problems. The comfort, efficiency, and cost-savings are well worth the extra effort.
Use the BTU Calculator at SupplyHouse.com to get an initial BTU load estimate.
