Dev had us out due to issues with a Rinnai Tankless Water Heater. Upon inspection we found a couple different issues with the Tankless Unit. We also called Rinnai tech support and they also pointed out some issues. Unit was throwing up a code 12. The first issue is the Flame Rod. A different plumbing company came out a year ago and cleaned the Flame Rod and cleared a Code 12. This should not have been done since the gaskets on the Flame Rod Kit are a one time use gasket. Second issue is the gas line. The gas line is not properly sized for the unit. Between the Tankless Water Heater, High Efficiency Furnace, and Stove Top, the BTU count is too high. Third issue is the Intake is pulling air from the mechanical room. This is not ideal and potentially choking the unit with no enough air. An air intake needs ran to pull air from the outside. Forth issue is the condensate line does not have an air gap, Rinnai pointed out that this is an issue and not up to code. We will be back out to inst