A calorie is the heat needed to warm 1 gram of water by 1 °C; kcal/h is the number of kilocalories removed or delivered in one hour. For a long time capacity in the refrigeration trade was given in this unit: "a 5,000 kcal/h unit", for example. With the move to SI units kW took over, but technicians in the field and old equipment labels still speak in kcal/h.
The conversion is simple: 1 kW = 859.85 kcal/h, roughly 860. 10,000 kcal/h ≈ 11.6 kW, 5 kW ≈ 4,300 kcal/h. Some sources also use the "frigorie" (fg/h); this unit, used for cooling, is numerically identical to kcal/h and only emphasises that heat is being removed.
When comparing catalogs and quotations, make sure the units are the same. There is a factor of about 4 between kcal/h and BTU/h (1 kcal/h = 3.97 BTU/h) and a factor of 860 between kW and kcal/h. The unit converter page has the kW–kcal/h conversion and a ready table.