Boilers are a prevalent form of home heating in older homes throughout the Northeast and other cold climates. Boilers generate heat by boiling water, which is then piped throughout the house to warm individual rooms as needed. Radiators get steam, and radiators or radiant heating systems receive hot water. Boilers can run on natural gas, heating oil, propane, electricity, or a biodiesel-oil blend.
Since the boiler’s output may be distributed throughout the house, it is technically a central heating system. However, there is often a short delay between turning on the boiler and the heat being distributed, which is not the case with other heating techniques.
Important Boiler Characteristics
The Condensing and Non-Condensing States:
There is no such thing as a non-condensing boiler. A condensing boiler recycles the surplus heat from the heating process to warm the water that is added to the boiler when it is cold. The ability to provide sufficient heat at reduced temperatures makes condensing boilers exceptionally efficient.
Unlike condensing boilers, non-condensing boilers have to operate at higher temperatures, losing some energy down the flue. The efficiency of a condensing boiler is better than 88%, while that of a non-condensing boiler is between 80% and 88%.
Sealed Combustion vs. Non-Sealed Combustion:
There are two main types of boilers, sealed combustion and open combustion. One with sealed combustion allows outside air to enter the burner and expels the exhaust gasses away from the house. The energy required to heat the air is wasted because non-sealed combustion boilers suck the air in, heat it, and then vent it out the chimney. In addition, the lack of venting required for sealed-combustion boilers means that no harmful gasses will be released into the environment.
Advice Before Making a Purchase
Climate:
A boiler could be an excellent investment if you reside in a cold area. In contrast, a central heating system might be unnecessary in a warm environment. A heat pump can provide both cooling and heating, so it’s worth looking into if that’s the case.
Type of Fuel:
If heating oil prices are high, a gas-fueled boiler could be more cost-effective than an oil-fueled one. Nonetheless, the availability of several fuels in your region will determine which one you ultimately select.
Sizing:
The efficiency of the boiler is essential, but its size is also crucial. The boiler won’t do its job well if it’s too small, and it’ll waste money if it’s too big. Consult an HVAC technician for assistance in selecting the appropriate boiler model and size; they should do an Air Conditioning Contractors of America (ACCA) Manual J calculation. Your home’s foundation, wall thicknesses, insulation levels, windows, air filtering, and other factors will all play a role in the final tally.
Cooling:
Because boilers only produce heat, a separate cooling system is required for air conditioning.
Using Energy Efficiently
The percentage of energy input that is transformed into usable heat is expressed as a boiler’s Annual Fuel Utilization Efficiency (AFUE) rating. High-efficiency boilers have an AFUE rating of 90 to 98.5 percent, and the minimum requirement for a new boiler is 80 percent. The higher the efficiency rating, the more expensive the initial investment, but the cheaper the ongoing maintenance.