Forum Discussion

Ro646a's avatar
Ro646a
Explorer
Jul 27, 2014

Dometic Penguin 2 stops running after a few minutes

My motorhome has 2 rooftop A/C units. The rear unit it a Dometic Penguin 2 A/C unit that was replaced about a year ago, before I bought the motor home. If I run it on shore power the fan cuts off after about 10 or 15 minutes and the compressor keeps running. If I run the fan only it will run all day. I have 114 volts and 228 volts at the motor home on shore power at my home.

If I run the generator it will run all day without any problem. The front unit is the original Penguin unit and it runs just fine all the time.

Has anyone experienced anything like this? Any thoughts as to what the problem might be?

Thanks in advance.

Roland
Class A
  • Ro646a's avatar
    Ro646a
    Explorer
    Aug 03, 2014
    UPDATE:

    Well, I got the new transfer switch and installed it. It was a very simple job. Unfortunately it didn't correct the problem with my A/C unit, and now I have another problem.

    Now my generator will not stay running. It starts right up and only runs as long as I hold the starter switch down. The transfer switch installation was very simple. I even checked every connection three times when I finished. I have wired things a thousand times more complicated than that in my life with no problems. I'm a former licensed electrician, but this has me baffled. The generator worked fine on our last trip two weeks ago.

    I already checked the fuse and circuit breakers on the outside of the generator next to the start switch, and I checked the coolant and oil levels. I also had a friend hold the start switch down while I checked for voltage output and there is no voltage on the generator terminals at the transfer switch.

    My generator is a Guardian Quietpact 7500 75D diesel model.

    Any advice?

    Thanks in advance.

    Roland
  • Ro646a's avatar
    Ro646a
    Explorer
    Jul 30, 2014
    dougrainer wrote:
    Ro646a wrote:
    Well I opened up the automatic transfer switch yesterday to check connections, etc. All the connections were tight and there was no obvious evidence of a problem, although the contacts were pitted on the generator side of the relay. I ordered a new transfer switch, but I doubt that it was giving me any trouble, since it is on the power cord side that I am having issues when running my rear A/C unit.

    Doug,
    You seem to be pretty knowledgeable about the Penguin II. Can you tell me how I would be able to identify whether or not my unit has the 12 to 5 button conversion kit? I have the 5 button thermostat controlling both my original Penguin unit up front and my "new" Penguin II unit in the rear.

    Thank you for the clarification, Doug. I have not received the replacement transfer switch yet. When I get the new one installed I'll check everything and report back. Thanks again for the assistance. :)


    One thing that may be a clue here, is that although I am able to select either unit 1 or unit 2 using the zone button, both number 1 and 2 are always visible on the display. I don't recall seeing both unit numbers displayed at the same time on the same style 5 button thermostat in my old Dutch Star, with the 2 Penguin units.

    Any thoughts?

    And thanks for all the assistance from all of you so far.

    Roland


    You will see both zones. The one that is "active" will flash. I made a mistake on my original post. IF you have a regular AC, no Heat Pump, you may not need the 12 to 5 conversion. The only ones I have done were Penguin 2 HP's. But, the 12 button regular board cannot communicate correctly with the 5 button system. ON the 12 button Board, you will see 2 soldered spade terminals to one side with the White neutral wire on one of them. There may be a white wire on both. The 5 button does NOT have those side by side Neutral spades on the board. According to Dometic, if you try to use a 12 button with a 5 button wall CCC you will get a "EE" error code. The 12 button ALL the low voltage quick connects are on the END of the board. The 5 button board these quick connects face straight up on the board. SO, if no EE code they installed the 12 to 5 board, but may have connected it incorrectly. Doug
  • dougrainer's avatar
    dougrainer
    Nomad
    Jul 29, 2014
    Ro646a wrote:
    Well I opened up the automatic transfer switch yesterday to check connections, etc. All the connections were tight and there was no obvious evidence of a problem, although the contacts were pitted on the generator side of the relay. I ordered a new transfer switch, but I doubt that it was giving me any trouble, since it is on the power cord side that I am having issues when running my rear A/C unit.

    Doug,
    You seem to be pretty knowledgeable about the Penguin II. Can you tell me how I would be able to identify whether or not my unit has the 12 to 5 button conversion kit? I have the 5 button thermostat controlling both my original Penguin unit up front and my "new" Penguin II unit in the rear.

    One thing that may be a clue here, is that although I am able to select either unit 1 or unit 2 using the zone button, both number 1 and 2 are always visible on the display. I don't recall seeing both unit numbers displayed at the same time on the same style 5 button thermostat in my old Dutch Star, with the 2 Penguin units.

    Any thoughts?

    And thanks for all the assistance from all of you so far.

    Roland


    You will see both zones. The one that is "active" will flash. I made a mistake on my original post. IF you have a regular AC, no Heat Pump, you may not need the 12 to 5 conversion. The only ones I have done were Penguin 2 HP's. But, the 12 button regular board cannot communicate correctly with the 5 button system. ON the 12 button Board, you will see 2 soldered spade terminals to one side with the White neutral wire on one of them. There may be a white wire on both. The 5 button does NOT have those side by side Neutral spades on the board. According to Dometic, if you try to use a 12 button with a 5 button wall CCC you will get a "EE" error code. The 12 button ALL the low voltage quick connects are on the END of the board. The 5 button board these quick connects face straight up on the board. SO, if no EE code they installed the 12 to 5 board, but may have connected it incorrectly. Doug
  • Ro646a's avatar
    Ro646a
    Explorer
    Jul 29, 2014
    Well I opened up the automatic transfer switch yesterday to check connections, etc. All the connections were tight and there was no obvious evidence of a problem, although the contacts were pitted on the generator side of the relay. I ordered a new transfer switch, but I doubt that it was giving me any trouble, since it is on the power cord side that I am having issues when running my rear A/C unit.

    Doug,
    You seem to be pretty knowledgeable about the Penguin II. Can you tell me how I would be able to identify whether or not my unit has the 12 to 5 button conversion kit? I have the 5 button thermostat controlling both my original Penguin unit up front and my "new" Penguin II unit in the rear.

    One thing that may be a clue here, is that although I am able to select either unit 1 or unit 2 using the zone button, both number 1 and 2 are always visible on the display. I don't recall seeing both unit numbers displayed at the same time on the same style 5 button thermostat in my old Dutch Star, with the 2 Penguin units.

    Any thoughts?

    And thanks for all the assistance from all of you so far.

    Roland
  • vance's avatar
    vance
    Explorer
    Jul 27, 2014
    My unit does not have the heat pump, so based on what's been said, I guess it is operating as it should. I just never run across a unit where the fan cycled.

    Thanks
  • dougrainer's avatar
    dougrainer
    Nomad
    Jul 27, 2014
    vance wrote:
    Does the system wiring have to be different for the new penguin 2? My unit is the front unit. The unit that came with the MH was working fine, just that the wife thought we needed a larger unit. We took out a 13,500 and installed a 15,000 and have had trouble ever since.
    The Tech told me, after working for weeks trying to figure out why the unit was acting like it did, that it was designed to operate the way it was operating. When the temperature gets close to the setting, the unit fan speed is designed to drop/slow down and if the temperature gets above the setting by so many degrees, the unit fan is designed to speed up. Not sure that I believe this, but so far no one has come up with a better story and I just live with it.
    Note that Roland's problem is with the rear unit and mine with the front unit. I don't know about Roland's change out, but for mine the original wiring was used and it was a penguin unit that was removed.???????
    Still looking for help.


    If they removed the 2007 Penguin and installed a Penguin 2 and did NOT install the 12 to 5 button conversion kit, the Penguin 2 will not operate correctly. Is your Penguin 2 a AC only or a Heat Pump? See my post about the 5 button older Penguins and the NEW style Penguin 2. The Penguin 2 control board is for the 12 button wall tstat CCC. That Penguin board is NOT compatible with the 5 button wall tstat CCC. If AC only, I would R&R the OTHER AC unit control board and install the 12 button board and purchase the new 12 button wall tstat. You CANNOT do this if your original units are Heat Pumps. Yes, on Auto, the fan speeds will change as it gets closer to the set temp(from hi to lo and then off). IF you have only Hi and LO fan speeds, you have a Heat Pump. The Penguin 2 has 3 fan speeds (lo/med/hi) and THAT can cause problems if mismatched with older Penguin Heat Pumps. Doug
  • Ro646a's avatar
    Ro646a
    Explorer
    Jul 27, 2014
    Doug,
    I somehow missed your post....good information...Thank you....I'll update and report back tomorrow if the rain stops.
  • vance's avatar
    vance
    Explorer
    Jul 27, 2014
    Does the system wiring have to be different for the new penguin 2? My unit is the front unit. The unit that came with the MH was working fine, just that the wife thought we needed a larger unit. We took out a 13,500 and installed a 15,000 and have had trouble ever since.
    The Tech told me, after working for weeks trying to figure out why the unit was acting like it did, that it was designed to operate the way it was operating. When the temperature gets close to the setting, the unit fan speed is designed to drop/slow down and if the temperature gets above the setting by so many degrees, the unit fan is designed to speed up. Not sure that I believe this, but so far no one has come up with a better story and I just live with it.
    Note that Roland's problem is with the rear unit and mine with the front unit. I don't know about Roland's change out, but for mine the original wiring was used and it was a penguin unit that was removed.???????
    Still looking for help.
  • dougrainer's avatar
    dougrainer
    Nomad
    Jul 27, 2014
    vance wrote:
    Roland, I have a Penguin that does almost the same thing. You did not say whether or not when the fan shuts down and the compressor continues to run, if the fan comes back on. Mine does come back on after a few seconds and sometimes at a different speed. This is my second unit, the first one quit completely after about 6 months. The Techs who worked on it changed boards several times and also changed out the thermostat (which was installed with the new ac). Nothing stopped the unit from cycling except putting the fan on manual high or low speed. I have not tried it while the generator was running.
    If you do find a fix, I would certainly be interested.

    Thanks, Vance


    See my post. The odds are they did NOT wire the system correctly if you have the new Penguin 2. Doug
  • vance's avatar
    vance
    Explorer
    Jul 27, 2014
    Roland, I have a Penguin that does almost the same thing. You did not say whether or not when the fan shuts down and the compressor continues to run, if the fan comes back on. Mine does come back on after a few seconds and sometimes at a different speed. This is my second unit, the first one quit completely after about 6 months. The Techs who worked on it changed boards several times and also changed out the thermostat (which was installed with the new ac). Nothing stopped the unit from cycling except putting the fan on manual high or low speed. I have not tried it while the generator was running.
    If you do find a fix, I would certainly be interested.

    Thanks, Vance

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