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Munchkins- Insider tips

GW
GW Member Posts: 4,302
I updated some of my notes on the M80-M140 series, we have a few loyal customers with these units (you know, phone notes, computer notes, field notes).

For the 925 controller, #13 allows for a post purge on the boiler pump. Factory setting is ZERO (no purge), do you Munchkin experts move these to one at all? ONE may be good to move the heat?

#18 is the stepped modulation upon startup on the heating mode. Factory is ONE meaning it’s on. ZERO means it’s off, which means it would go direct to hi fire. Do you ever go to high fire off the bat?

I lost track of when they stopped making the M series. i bet there are many thousands within an hours drive

Thanks, and please share more insider tips.
Gary Wilson
Wilson Services, Inc
Northampton, MA
[email protected]
kcopp

Comments

  • kcopp
    kcopp Member Posts: 3,819
    Two thumbs up.... good stuff!
  • GW
    GW Member Posts: 4,302
    c'mon, share a Munchkin tip!
    Gary Wilson
    Wilson Services, Inc
    Northampton, MA
    [email protected]
  • kcopp
    kcopp Member Posts: 3,819
    One thing I remember was that the way the air intake was above the inducer would drip on to the motor and short it out. This was especially if there was cross contamination.
    Suggestion was to for a small piece of metal to divert that away to the side.
    I used this w/ a customer that went through 3 motors in 4 years. (ME shared that one)
  • GW
    GW Member Posts: 4,302
    Ok good one, yet I'll need to visit one to see what you mean.

    I thought the intake was a simple hole in the back of the munchkin.
    Gary Wilson
    Wilson Services, Inc
    Northampton, MA
    [email protected]
  • kcopp
    kcopp Member Posts: 3,819
    This was on a T-50 and/or T80.
  • hot_rod
    hot_rod Member Posts: 15,023
    Do you have this 50 pager? Sent out 7/3/08. I have some that wholesalers put together also.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Steve Minnich
    Steve Minnich Member Posts: 2,674
    I could use that one Hot Rod. Could you email it to me?
    I just condemned one yesterday but not much troubleshooting necessary.
    Steve Minnich
    Minnich Hydronic Consulting & Design, LLC
    [email protected]
  • Bob Bona_4
    Bob Bona_4 Member Posts: 2,083
    Me too, Bob, if I can get a copy.
  • hot_rod
    hot_rod Member Posts: 15,023
    I sent a few to Stephen as a Dropbox link, if they arrived Ok I'll pass them along.
    e-mail me your address
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • GW
    GW Member Posts: 4,302
    [email protected] thanks, looking forward to it
    Gary Wilson
    Wilson Services, Inc
    Northampton, MA
    [email protected]
  • Tim McElwain
    Tim McElwain Member Posts: 4,480
    I have a ton of tips on Munchkin from my Troubleshooting Manual that I wrote several years ago. I do not want to spoil the fun so I will hold off on sharing them. In fact we just went through my manual this week in the Mod/Con class I ran. That along with several others on Mod/Cons I have written. I got a lot of my info from Brian French, John Sawyer, Jeff Cook and Chuck Shaw all who worked at HTP.

    I would love a copy from you Hot Rod just to compare with my information.
  • Steve Minnich
    Steve Minnich Member Posts: 2,674
    Just opened it, HR. Thank you.
    Steve Minnich
    Minnich Hydronic Consulting & Design, LLC
    [email protected]
  • GW
    GW Member Posts: 4,302
    Thanks got it
    Gary Wilson
    Wilson Services, Inc
    Northampton, MA
    [email protected]
  • 8/25/15 Check the black molex plug; the outside wires (brown and blue) should read 24-27 volts DC. If you check the same wires at the circuit board, they should read 24-27 volts AC.

    Incoming gas pressure should be 8-10" wc, outlet side should be -.01 wc

    Check voltage at the flame probe, from probe to ground - you don't need to disconnect the wires. There should be 42-44 volts; if less than 38 volts, upgrade to the 925 board (black transformer).

    Check rectification by pressing and holding S4, continue pressing S4 to get to d7 which will tell you how many µamps (micro amps) coming from the flame probe. The range should be 3 - 4½ µamps.

    Also, check the voltage readings at the molex plug connected to the fan, the one with 4 wires. You should have 24-40 VDC at the red and blue connections.
    Often wrong, never in doubt.
    Steve Minnich
  • Hey, Hot Rod: Me too, please! [email protected]
    Often wrong, never in doubt.
  • unclejohn
    unclejohn Member Posts: 1,749
    Had a call yesterday from a customer with a 140m. Wanted too know if I was a munchkin "expert ". I asked what the trouble was. It won't run he said. I asked what was the error code. he said there is none. I asked if the tstat was set high enough. A pause and then it's running now. I guess I am a expert but would also like to have that trouble shooting book. Hot Rod. [email protected]
    Steve MinnichSWEIkcopp