WaterFurnace heating and cooling equipment carry the build date inside the serial number. We know 2 serial formats for this brand; the decoder tries each one and shows every reading that fits.
The first two digits are the year and the next two are the month.
180100228 reads as January 2018.
One source Building Intelligence Center
The first letter is the year (A is 1985 through Z for 2009, then A again for 2010). The second letter is the month.
UJ1087 reads as September 2004.
One source Building Intelligence Center
The indoor unit of a geothermal system is expected to last 20 to 25 years. The buried ground loop is expected to last 50 years or more.
How long does a geothermal heat pump last? · Should I replace my furnace? · to be sourced in Stage 3
Mitsubishi Electric · LG · Fujitsu · Gree · Bosch (heat pumps and geothermal) · ClimateMaster
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The age you just looked up is the kind of fact that gets lost. A written record of serial numbers, install dates, repairs and who did the work saves the next owner, inspector or insurer from guessing.
A lifetime logbook for the house, organized by system, with room for serial numbers, install dates, repairs and contractors. It stays with the house for the next owner.
Galvanized, polybutylene, cast iron and the sewer line: what fails, what it costs, what insurance won't cover and how to decide.
A buyer's guide to older homes: wiring, pipes, lead, asbestos, insurance refusals and what the repairs actually cost.
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