The time required to install a new boiler depends on a variety of factors, including the type of boiler to be installed, the complexity of the installation, and the availability of parts and equipment. Generally speaking, directly replacing a single boiler may take anywhere from a few days to several weeks (or even longer) to complete.

This estimate does not include the time required to procure the boiler—depending on the type, size, and selected options of the boiler, procurement time can range from a few days to several weeks or even months. Generally, small condensing boilers have shorter delivery times. Fire-tube boilers have longer delivery times because this design allows for more customization, thereby extending production time.

For simple boiler replacements, where the new boiler is installed in the same location as the old one (direct replacement), the installation process can typically be completed more quickly. However, if the installation process is more complex, such as requiring new piping, ventilation, or exhaust systems, the installation process will take longer.

It is worth noting that the installation process may also be influenced by factors such as local building codes, weather conditions, and the availability of skilled labor.