Navien Combination CH-180

I recently installed a natural gas Navien CH-180 combination heat and hot water unit for a small apartment for a customer. It ran fine for about 3 weeks, then kept going on 03 error codes (ignition failure) sporadically, then once de-powered, would run fine until the next time it went out.



I worked with tech support, and they rushed me out the parts they thought were faulty, first they sent a PC board, it ran fine for a week after that was replaced, then the same error code appeared. They then sent out an air and a gas pressure switch, same deal, ran fine for 1 day, then 03 error code.



They insinuated I may have a gas delivery problem, I checked the gas pressure, and it was within the parameters.



Finally I got the manufacture's rep out to the job, he tested the differential pressure, made some adjustments, and determined that we had a defective gas valve. They won't replace a gas valve on these units, so instead, they gave me a whole new heater and are paying for my replacement of the new heater, and my previous service calls to replace the other parts.



I'm not sure if I would install another one of these units based on this experience, however the people at Navien were very helpful, and so was the manufacturer's Rep.