Honeywell control failure on new Buderus

Unknown

I'm not Joe from Buderus but we use the L7248 control on our MPO boilers. The Error Code 8 generally indicates the possibility of Reverse Polarity to the boiler control.You can get the burner to turn back on by resetting the control which involves holding all three white buttons down for 60 seconds. Check you polarity at L1 and L2 and all should be fine. Hope this helps.

Glenn Stanton

Manager of Training

Burnham Hydronics

U.S. Boiler Co., Inc.

Saggs

Just installed a new Buderus GB115-21 direct vent. This unit came with the new Honeywell digital operating control/ relay with the Riello burner package. Unit ran the radiant zone for about 3hrs then failed. The LED was saying "Err 8". In the troubleshooting section it lists trouble codes for numbers 1-7 but no #8 ? Unit still had 26 volts output on the "T-T" terminals but could not be reset or made to run. I put an old style control on for now but this doesn't give me much faith in the thing. I did notice that the temp probe appeared to be right on the money as far as temp accuracy.

Saggs

Glen, Thanks for the advice! I'm surprised they don't mention this in their info sheet that comes with the control. Maybe I overlooked it?

Unknown

It's not there!

Not sure why but it isn't in the sheet that comes with the control as far as I am aware. Here is a scan of their control literature from the Honeywell website.

Glenn Stanton

Manager of Training

Burnham Hydronics

U.S. Boiler Co., Inc.

Robert O'Brien

I've

heard that the Riello can backfeed current causing this problem

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Saggs

Just talked to a friend of mine who was getting an error code #4 and was due to the post purge on his DV riello being too long. He decreased the post purge time from 45 secs to 30 seconds and the error code never reappeared? You'd think they would have all the bugs worked out b4 they upgraded the control

Leo

There was a recent Post

There was a recent post on one of the sights about this. Get a hold of Joe, Riello or Honeywell. The Riello control gives a bleed back and the Honeywell control thinks it is a run away boiler and locks out. It will do this two or three times then dies. They described a cure, an isolation relay I think but I can't remember the specifics.

Leo

S Ebels

Probably

It wouldn't surprise me if the control had some power stealing stuff going on internally, or a power stealing stat in the mix maybe. Polarity, as Glenn said, is critical on all equipment with electronic control.