Can a new installation of a fin type pool heater less than 250 MBtu be installed downstairs in a house?

The installation of a fin type pool heater less than 250 MBtu is not permitted in a basement or downstairs area of a house due to safety and ventilation considerations. Pool heaters, especially those that burn gas, require proper air supply and ventilation to ensure safe operation and to avoid the accumulation of carbon monoxide or other harmful gases.

In residential settings, installing such appliances in enclosed spaces without adequate ventilation can lead to dangerous situations. Regulations are in place to ensure that gas appliances are installed in appropriate locations where they have access to adequate fresh air and where ventilation can effectively expel combustion byproducts. This is why options suggesting variations like "if gas piping can support gas input" or "if pool heater is direct vented" may appear feasible in theory but do not align with the strict safety regulations governing the installation of these appliances.

In summary, the guidelines prioritize safety, meaning that a fin type pool heater less than 250 MBtu should not be installed in a basement setting, where the risks associated with gas combustion and inadequate ventilation are heightened.