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dayakster's avatar
dayakster
Explorer
Jul 22, 2014

Need a hint please! RE: 97 Allegro Bus/DuoTherm/onan gen

Brought our new 97' Allegro Bus home on April 3rd of this year. Winter didn't ended up going away till late May then my mother became ill and passed on....so, we now have her place finished and are back to our own life in progress.

I've got the leveling system and Norcold fridge figured out. The Norcold was real nice how it searches for the optimal power supply automatically which in my case right now is AC as I've got it plugged into the house.

Ok, my question is for the Duo-therm control for the A/C. I would like to fire up the generator and test the A/C units with that because I'm afraid of tripping my breaker. I know not to use both units at once on a household line but I may try doing a zone at a time. My fear stems from the fact that I think this electric line also carries our water point pump and I don't want to mess with that at all.

The operator's manual for the Duo-therm says nothing at all about power source (the genset manual doesn't seem to help me answer this either.....I have a huge folder full of owner's manuals about transfer switches, etc. at my finger tips I just don't know where to start.

I need to know....after I start up my generator how can I be sure that the A/C units are going to use it for a power source without unplugging the MH and my fridge? I just plugged the Norcold in yesterday and don't want to unplug it yet....but will if I have to.

Thanks
Class A

17 Replies

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  • accsys's avatar
    accsys
    Explorer
    Jul 23, 2014
    Unplug your shore power and the Norcold should switch to propane and continue operating. Start the generator and the once it supplies power to the coach, the Norcold should switch back to AC. You can also run the air conditioners from the generator without problem as long as everything is working properly.

    Just in case you are not aware of it, there is a website ran by Tiffin owners for Tiffin owners (and others if they want to get on it). It is located at Tiffin RV Network. On the left side of the page the fourth item down is the Forum. Go there and you will love it!!!
  • dayakster's avatar
    dayakster
    Explorer
    Jul 22, 2014
    Got it wa8yxm. My gen manual doesn't say anything about holding the stop button first though. It just says hold start button for no more than 10 seconds if no start wait at least 30 secs and try again.

    Thank you!

    ps...I see you're saying the Norcold will read the gen power as AC. I think I'm getting this!
  • wa8yxm's avatar
    wa8yxm
    Explorer III
    Jul 22, 2014
    Look for a manual for an automatic transfer swith.. Or if you wish to shortcut.

    Pull the shore cord.. The Norcold should switch to GAS within a couple minutes, verify this then start the generator.. MOST onan generators start like this.

    Hold the STOP button till the light comes on.. I like to hold it another 10 -30 seconds. Then push START (The 30 second hold starts the fuel pump and primes the system, NOTE that is for gas models, Should work OK with Diesel as well).

    Once it starts release the button and sit back, in about 1/2 to 2 minutes you should hear a CLUNK and/or notice interior lights get brighter.

    Once that happens the Norcold should switch back to A/C

    Now start your Air conditioenrs

    TO SHUT DOWN GENERATOR... NOTE This time let it run at least an hour, 2 would be better, also if you have water in the system fire the heater up)

    Turn off A/C first (And water heater in fact ALL big loads) THEN push the stop button, wait at least a minute before restoring shore power.

    Short: UNPLUG first, THEN start generator
    Shut generator down first THEN plug back in.
  • dayakster's avatar
    dayakster
    Explorer
    Jul 22, 2014
    Hmmm...I'm just looking at the generator section in the little handbook for the bus itself and it reads,

    "The 120 volt output of the generator is connected directly to an automatic change-over switch. With the gen power plant operating, power is available at all of the 120 volt power outlets in the MH just as if the cord were connected to an external source."

    I still think I'll unplug first though.
  • dayakster's avatar
    dayakster
    Explorer
    Jul 22, 2014
    Thank you both for your replies.

    I think to be on the safe side I will unplug first just to be safe then if I learn otherwise I'll know.

    Thanks again! PS. The generator hasn't been run since April.
  • darsben's avatar
    darsben
    Explorer II
    Jul 22, 2014
    MountainAir05 wrote:
    On most the gen set overrides the shore power.


    I think the opposite ! On mine the Shore power overrides the genny. If the switch in your home senses shore power it will use shore power.
    My thought is to switch the fridge manually to propane/gas and then unplug the shore power. Conduct the a/c test then replug the shore power and put fridge back on automatic. Run the genny with just the fans running on the a/c for a little while just to make sure everything is functioning well on genny then load up each a/c one at a time. Check for surging of the genny after turning each one to a/c. I have a feeling the genny has not been used in a while.

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