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Laars Mascot FT Error Code E66

fosser2 Member Posts: 1
Hey All -

I recently had a Mascot FT (MFTCW199) installed in my house to run both infloor slab heat as well as my domestic hot water. The boiler is constantly throwing an E66 error. I have replaced the main board as well as the mixing valve. After spending 6k+ on this install I really cannot afford to just throw it in the trash and start over. Does any of you have any experience in this area or seen this issue before? Thanks for helping me out!


  • lchmb
    lchmb Member Posts: 2,997
    sounds like a wiring issue could be the next thing to check. Have you contacted Laars to start a file on the issue and see what they recommend? Has your installer been back to check things?