Arrived on site customer stated that they have no hot water upon inspection found that we will need to contact tech support to diagnose the issue. Contacted tech support and found that they believe the burner assembly needs to be cleaned but I strongly feel that the igniter assembly needs to be replaced due the condition it is in having an ignition failure code 111 and the after removing and cleaning found that the new error code was a 121 which is flame loss or flame sensor failure which means after cleaning we were able to produce a flame for a brief second before coding out. Recommend that the unit be flushed as well because it has not been flushed in approximately 2 years stated by the customer. Also found that the condensate drain line has brass on it which is prone to pit out and leak due to acidity in the condensation. Gave options on performing all work and customer would like to start with cheaper options and then move forward to more expensive. Collected for tech support toda