<html><head></head><body>Perhaps a coincidence but something similar happened a couple weeks ago at my place. The induction fan was ramping up to a very high speed (we could hear while upstairs). It was ramping up through speeds trying to confirm it could push a draft through the flue. <div><br></div><div>The error code indicated a pressure switch was malfunctioning. With some research I found out this was common failure. One of the posters mentioned they hit the pressure switch with the handle of a screwdriver to unstick it. I did that and it worked like a charm but I also ordered a replacement which I installed last week. I wonder if the issue was just some gunk (maybe ice) I knocked loose. </div><div><br><div><div><div class="gmail_signature"><div>-- <br>Tim Laurence</div></div> <p class="gmail_quote" style="color:#000;">On February 9, 2026 at 1:24:42\u202fPM, Mikalai Birukou via kwlug-disc (<a href="mailto:kwlug-disc@kwlug.org">kwlug-disc@kwlug.org</a>) wrote:</p> <blockquote type="cite" class="gmail_quote"><span><div><div></div><div>There are these little pipes that go between enclosed area in furnace <br>and membrane switches to detect presence of pressure difference between <br>normal/room and that enclosed area with air/fumes flow.<br><br>Other season, there was a burned ash in one of pipes, after burner, I <br>suppose.<br><br>One more season, I gently blew in and out of pipe into membrane switch <br>to hear it flip. It got unstuck, and continued proper operation.<br><br>This season, a pipe had a drop of water in it. Surface tension in a <br>small radius obvious stopped pressure difference from pushing membrane.<br><br>I guess, cleanup includes dusting furnace, and blowing through some <br>pipes. :) Noting that three events happened over 15 years.<br><br><br><br>_______________________________________________<br>kwlug-disc mailing list<br>To unsubscribe, send an email to kwlug-disc-leave@kwlug.org<br>with the subject "unsubscribe", or email<br>kwlug-disc-owner@kwlug.org to contact a human being.<br></div></div></span></blockquote>
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