A heating designer is asked to create a three zone radiant floor heating system using a 5-ton (60,000 Btu/h) geothermal heat pump as the primary heat source, and a mod/con boiler as the auxiliary heat source.
Figure 1 shows a hydronic system that's intended to supply four panel radiators, each with its own thermostatic radiator valve, and an indirect water heater from a gas-fired sectional cast-iron boiler.
An installer is asked to connect an old (but still working) propane-fueled cast-iron boiler, which was salvaged from another project, to a slab-on-grade floor heating system in a new workshop.