Tech Tips for Servicing Buderus Boilers
Cross Contamination a Common Cause of Boiler Failure
Cross contamination is the recirculation of exhaust gases being pulled back into the boiler through it's fresh air intake. Mapping out sidewall ventilation before installation is crucial to prevent this. Venting should not be installed into an alcove where air currents can sometimes keep exhaust hanging in the area to be sucked back in.. A minimum of 3 feet from an inside or outside corner and at least 5 feet below an overhang is necessary so that the fresh air intake does not draw in particulates from the nearby exhaust that will foul sensors within the boiler, causing it to shut down,
Failures from cross contamination are one of the most common reasons for calls in to Buderus's tech support line. Detailed venting information can be found in section 6.7 of the installation manual.
Cleaning a Buderus GB142
The GB142 boiler is designed for ease of maintenance. 1) Pull the top cover off of the boiler. 2) With a spray bottle containing a mixture of 80% water and 20% mineral oil, spray the coils while keeping the ignitor and ionization rod dry. 3) Put the cover back on and run the boiler to high fire for 10 minutes. 4) You may nedd to repeat steps 1-3 more than once if the boiler hasn't been cleaned regularly and is very dirty. 5) When the coils have been satisfactorily cleaned, pull the bottom cover off of the boiler and flush out all debris, along with flushing out the condensate bottle.
Starting a Bosch Greenstar Boiler
Before starting up a Greenstar boiler, remove the bleed screw on the front of the circulator pump and use a screwdriver to rotate the shaft. These boilers are water tested, so the impellers may be static after storage, which would prevent circulation.
6A Error Code on the Buderus GB142
This is a "no ionization after ignition trial" message. The ionization rod can be one of many problems causing the boiler not to fire. Follow these steps when experiencing a 6A error code:
1) Check that the gas cock is on and check static pressure at the valve. 2) Start the unit. Does the fan start? 3) To know if the fan starts, check the ignition glow in the window. 4) Does it glow for a minimum of 4-5 seconds? 5) If there is no glow for a minimum of 4-5 seconds, replace the UBA to a 3.6 UBA. 6) Once the ignition glow has been established at 4-5 seconds, check to see that the gas valve is getting power. 7) If the gas valve is getting power, then ohm out the pins. 8) If the gas valve is not getting poer, then the wiring harness is bad or there is a problem with the consate bottle being plugged. 9) Pull out the condensate bottle and flush it out. 10) Check the boiler-to-condensate bottle connection with your fingers for blockage.
3C Error Code on the Buderus GB142
A 3C error code refers to a bad connection to the fan or a faulty fan. Ohming out the wires back to the 81 pin connector behind the UBA will determine if the wiring harness or the fan itself needs to be replaced.