Analysis of the results

Analysis of the results
The results from the SPF calculations of the different heat pump installations in field is compared with the results obtained from the laboratory data used in calculation models.  
Ground source heat pumps Most of the heat pumps installed in field operates both in floor heating mode and produces domestic hot water. The measurements include both kind of operations and the results are presented in Table 14and Figure 7 below. SPF for domestic hot water production is always lower compared to operation in heating mode. The energy balances is not 100% complete for the field measurement, which is quite common in field measurements, since heat losses are present, but cannot be measured directly as they can be in the laboratory.