Assertion: geothermal heat pump | /r/HasProperty | expensive to install
Facets:
Source sentences:
text: Geothermal heat pumps are more expensive to install because the system needs to be installed underground.
text: Geothermal heat pumps are more expensive to install than air-source heat pumps, as much as three times as much, because ground-source pumps require you to dig down to a heat source and involve more complex heat transfer systems.