If the air temperature entering a heater is too low, what is a common result?

When the air temperature entering a heater is too low, a common result is sweating on the gas side of the boiler. This sweating occurs because the cold air can cause condensation when it meets the warmer surfaces of the boiler or gas side, leading to moisture buildup. This moisture can create several issues, including corrosion and efficiency losses.

In contrast, low air temperatures are less likely to directly lead to overheating of the fuel or failure to ignite the combustion in a well-designed system. Overheating typically relates to excess heat rather than low air temperatures, while ignition failures are more often tied to fuel-air mixtures being out of the proper range, rather than simply low intake temperatures. Similarly, while corrosion can happen as a consequence of moisture, it is not an immediate result of low air temperatures like sweating is. Therefore, sweating on the gas side accurately reflects the effects of low inlet air temperatures in heating equipment.