Arrived onsite to investigate no heat in one zone. Upon arrival, the radiators in the bathroom and kitchen were cold. We went downstairs and found the boiler operating properly; however, the pipes for the kitchen zone were not circulating hot water. I attempted to purge the zone, but no water came out, indicating the zone may have been frozen. I increased the system pressure from 12 PSI to 15 PSI, as the boiler gauge reads low. I traced the zone piping into the crawl space and found it ran into the slab to the kitchen. After checking the piping, it began to warm up. I purged the zone again and achieved proper water flow. I allowed the zone to run for a period of time, and the radiators heated up. System is operating properly at this time.
