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Hi, I have a Bosch WR250 tankless gas instant water heater. My problem is i am not getting a spark at the pilot when the hot water is turned on,the red light flashes after 10sec. I can here the (water/spark)generator turning but i get nothing. I have checked all electrical connections and they seem fine, any suggestions please?

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Flashing red light indicates not enough pressure on the input cold water. I had this problem when the small filter was gummed up with ****. Remove the water input nut and inside is a small removable mesh filter. Also the hydro power unit that you hear whirring has a even finer mesh filter. It can also be cleaned out.

Posted on Jun 27, 2009


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What leads you to suspect that pilot blew out instead of another problem?
Fact that pilot will not relight, indicates other factors at play.

Open following link for Bosch troubleshooting resources including manual, and Bosch contact info:

Best place to start is your manual.

1) Manual recommends 'cleaning by authorized person, never less than once a year.'
Tankless water heaters, and most newer tank-type gas water heaters, are highly technical and finicky devices that require continual maintenance, with tankless requiring 'yearly' maintenance while tank-type require 'periodic' maintenance.
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Upvote the help.
And take advantage of fixya expert assistance live.
For a price, expert works with you while you work on water heater or any do-it-yourself project.
Fixya is always less expensive than a service call.

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I have a Bosch 125 BNG gas tankless water heater. Pilot light will not light but spark is there. Solution and where do I get parts assuming needed.

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