The installer underestimated the size needed for this house and therefore it took much longer and cost more than initially estimated. Initially a 1.8 t (2 tons) heat pump was required, but in the end a 2.7 t (3 tons) was installed. Also, 2 horizontal loops (152 m (499′) each) in yard were planned, but more heat was needed so 2 vertical holes were later drilled (45 m (148′) each). Plastic piping with glycol was used for all 4 loops.
The house (255 m2 (2743 sq. ft.), 2-storey) was previously heated with an oil furnace, therefore duct work already existed in house. The oil heat used to be inconsistent, real hot then cool, but now with the new system heat remains more consistent as fan constantly turning on and off. Fan is electric, therefore does not work when power goes out. If heat pump fails, there is an electric heater connected as a backup heat source. This system also cools the house during the summer, therefore system is used year round. System is also hooked up to the hot water tank to preheat water.
While system was not working correctly, noticed an annual savings of $1200, averaging $100/month. Once working correctly, hope to have a $1500 annual savings.
