Upon arrival inspected boiler. Boiler is on/running for a demand of hot water. Once boiler demand stopped for hot water. Checked Aquastat setting adjust Aquastat to have boiler switch demand to call for heat. Check circulator pump. Check flow at supply and return. Ok Ran and monitored heating operation. Checked all radiator with customer to be okay. Explained to customer that boiler was calling for a demand from the indirect hot water storage tank. Once tank is filled demand will switch to run heat. System is back up to normal operation @ this time. View visual findings from this job here - https://visionshare.xoi.io/?id=XA-90AE-2824A03014914353A4E6A6CCD54DC865