Click here to Find a Contractor in your area.
Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit

Laars low water flow board

Got an old JVS-100 found cool. Would fire for 30 seconds off for about 2 minutes. Regular as clockwork. Traced it to the low water flow board.

NOW: when it wasn't firing the relay on said board was clicking on & off like a turn signal. The whole time. And when it did it sent a split second of voltage to the spark control which in turn sent voltage to the gas valve so one of the solenoids in the valve, guessing pilot, was also clicking on & off like a turn signal. Obviously not right.

So, do we have a flow issue? Bypassing the board to get heat on a below zero night, sure doesn't seem like it. Got the loops hot in no time so didn't appear to have a flow problem. Hate to order a new board to have it do the same thing (less the turn signal). Just started this.

Any thoughts? Thanks!


  • unclejohn
    unclejohn Member Posts: 1,718
    Is there

    a senser conected to the board? Maybe it needs to be cleaned.
Sign In or Register to comment.


It looks like you're new here. If you want to get involved, click one of these buttons!