Heat pump and method for installing the same

A heat pump, comprising:

• a refrigerant circuit configured to circulate flammable refrigerant, the refrigerant circuit having a compressor, a utilisation-side heat exchanger, an expansion device and a heat-source-side heat exchanger connected by piping;
• and
• an indoor unit configured to be arranged in an indoor space, the indoor unit including
• an outer casing having a top and a bottom opposite the top, the top being the uppermost surface of the outer casing, the bottom supporting the outer casing, and
• a sealed container accommodated in the outer casing, the sealed container having a bottom and a top and accommodating at least one of the compressor, the utilisation-side heat exchanger, the expansion device, and the heat-source-side heat exchanger,
• the sealed container having a release opening to exhaust leaking refrigerant to an exterior of the outer casing of the indoor unit, the sealed container including a chimney having a first end and a second end, the first end of the chimney being in fluid communication with an interior of the sealed container, and the release opening of the sealed container being arranged at the second end of the chimney,
• the release opening being disposed above the top of the outer casing, and
• the refrigerant having a higher density than that of air.