The overall condition of the plumbing system is iv very good condition. The water pressure is set to psi, the entire home has has the water piping replaced with PEX, the valve stops, traps, drains, etc are in good condition. The homeowner did want the 3 year old Rinnai tankless water heater flushed and inspected. He has has random error codes in the past. After checking the error code history 2 error codes came up, both of them were the error code 11 which indicates "air supply, ignition, or flame failure." The last time this happened was in November of 2025. The water heater has 1/2" gas running from the 3/4" line. The 1/2" includes a short nipple, valve, whip, and sediment trap. We also measured the btu load on the gas meter is approximately 1,453,000 btu. The meter in place is an AL-1000 which has the stated capacity of 1,000,000 btu, but AGL states it can sustain approximately 1,500,000 btu. The failure may be caused by either one of these situations, recommendation is to increase