coleman basement ac, works ok on 20a but #2 not coming on while on generator?

[mrd341]

hello all, i am old, but new to rv'ng and have been wrestling with the basement ac on my 3 week old 2003 winnebago adventurer 35, w 30k miles. with the great info gleemed from this forum so far, i have been able to repair quite a few odds and ends in the motor home including the diagnoses of a bad outdoor fan capacitor on the ac for which i had to remove the unit to open up and replace, which wasn't "too" bad of an experience over all, but now i have a strange problem that has me stumped! i have the rv (which is 30amps) in my driveway connected to a 20amp home circuit, everything seems to work as it should, i turn the thermostat to cool, the indoor fan comes on, followed by an amp spike to 19a as the #1 compressor kicks on, (outdoor fan on low) then the amps settle down to a steady 11a until the #2 comp kicks on a couple of minutes later with a spike to 19a,(outdoor blower on high) then everything settles down to a steady 16 to 17amps and cooling seems fine. while testing it on generator power (5500) everything is the same, except the #2 compressor does not kick on and the amps remain steady at 11a. the air still runs cold at the ceiling vents, just not as much as with both 1 & 2 on with the 20a line! Any help would be appreciated, thank's,  dennis 

 

[John From Detroit]

Best guess. You have a 50 amp RV right.

Generator will have TWO Circuit breakers. likely 30 amp but possibly a 30 and a 20. one of them on one off (Tripped and off are same position most likely).

 

[Alfa38User]

One possibility is that the relay for the second compressor is faulty and requires replacement. The relays are located near the capacitors you replaced previously. Not an unusual problem BTW, I have that problem now on my trailer, hope to troubleshoot that in the Fall.

 

[mrd341]

thank's for the quick responses, the electrical plug coming out of the transfer switch is a 30 amp plug and i have it plugged into my home (120v 20a) outlet with a 120 dogbone, the ac seems to work as it should with both #1&2 compressors kicking on at the right times although the amp draws, seem to be a little low from what i am reading but the unit is cooling well with #1 running at 11a and #2 kicking in with 16a steady while running. when i start the generator, everything shuts down for a second and then #1 kicks on and stays running at a steady 11a, but #2 does not come back on at all with the gen running. i have not replaced any capacitors except the outdoor fan capacitor because the unit was tripping breakers and shutting down (overheating) because the outdoor fan was not coming on when i got it, i had to remove and reinstall the unit to get at the od fan capacitor! i will check the gen breakers and report what i find, thx  dennis

 

[mrd341]

the gen is an onan 5500 with two breakers, one 20a white and one 30a black just below it, they both appear to be ok and not tripped, i moved them both back and forth and although they do not have a strong spring "click" sound when tripping them back and forth (almost like one of those "silent" light switches) like i am use to, they both seem to be ok?

 

[mrd341]

i started the generator just now (temp here is an "unusual" 90deg's) set the thermostat to cool at 70, the first compressor kicked on and was steady at 11amps, second compressor did not kick in at all, tried flipping the breakers on the generator one at a time and there was a noticeable difference in in the gen rpm's when i flipped them back on, so they appear to be working ok. shut the generator off and waited for a few minutes for the ac to kick back on with the 20amp shore circuit, which it did, then the second compressor kicked on and they are both running fine at 17amps and are cooling the unit down like they should! can't figure out why the #2 will not come on with the increased useable amps of the generator? the gen has only 124.0 hrs on it.

 

[mrd341]

ordered a new start, run capacitors with a relay for the #2 compressor to see if that will make a difference.

 

[youracman]

ordered a new start, run capacitors with a relay for the #2 compressor to see if that will make a difference.

At the age of your unit, it's probably a good idea to install the parts you ordered ........... and keep the  old ones for "on the road" spares; cuz it doesn't seem logical that the #2 compressor runs on shore power and not on generator power....due to faulty caps, etc.  I don't believe that resonates with you either.

Just for grins, I looked up the service manual for an Onan 5.5 and yes, it shows the 2 ckt breakers in the "Connection Diagrams".  I included a pic of the page.....see below.  No surprises there, of course.  It appears that for load sharing or whatever, they have put one compressor on each of the two breakers.

The 2nd pic is one I wrestled out of the wiring diagrams on the WGO site ( https://winnebagoind.com/product-resources/product-information ) where they don't show a 2003 Adventurer Model W, BTW ...... so I chose a Model U.  On the upper rt hand corner the Automatic Transfer Switch (ATS) is depicted.  I really think you need to find that ATS and remove the cover (if the location isn't obvious, someone with a 2003 Adventurer will hopefully chime in.)  I don't even own an ATS, but from years of reading forums, it is JMHO that if one is having loss-of-power-type problems, the ATS (or often the wiring/connections within the ATS) should be considered "guilty" until proven "innocent".  With the "Power Cord" unplugged (and the generator running) measure the potential on the connections in the ATS associated with the "Conduit And Wire From Generator".  You should see the generator output voltage from the hot wire "CB1" to the white wire adjacent to it and also from the hot wire "CB2" to the white wire adjacent to it.  Note: In some installations the jumper shown is used; in others it is not.

SOoooo....... assuming the generator "passes" use your voltmeter to measure the potential on what they call the "Main" from the Red (Hot) to White (Neutral) and from the Black (Hot) to the White (Neutral).  You should read the generator voltage (or very near it) on each of those legs.  If not ............. the ATS is almost certainly faulty (or a connection is loose).

SOoooo ..... IF the ATS passes, you will note that the dwg shows a label which is supposed to be below the cover plate for the coach breaker panel.  Evidently there is one labeled "A/C Circuit 1" and another labeled "A/C Circuit 2".  One of them may be tripped.

This is just my $.02,  Dennis.  If I have the wrong slant on things there are a lot of experts in the electrical power area on this forum (I ain't on of 'em) and they will set it straight...... but from what I have read here, I don't believe there is a thing wrong with your #2 compressor.

I know you will keep us posted on your progress/final results.....and TIA for that.

Best................... ed s

 

[mrd341]

thank's for the info! this unit is driving me nuts because there are so many different things that could be going on with it! i am still not 100% sure whether the #2 circuit is coming on or just "trying" to come on because it is illogical for the second one to be on and have the low amps (16-17) while both are running. when i had the unit out, i could tell that the #1 circuit was working and when i put my hand on the #2 compressor, it "felt" like it was on, but now in hindsight, i am thinking that it might have just been carry over vibrations from the #1 compressor because at the time, i was more concerned about getting at the od fan capacitor,as i knew that the fan was not coming on as it should and was thinking that the compressors were overheating because of it! i ordered a clamp on multimeter and will install the new parts for the #2 circuit when they get here to see if it changes anything. i am now wondering if i can switch the incoming power from the #1 circuit to the #2 circuit just to see if #2 kicks on or not? thank's again!

 

[AStravelers]

If compressor 1 and 2 work normally on shore power and then compressor #2 will not come on with the generator, you DO NOT HAVE A PROBLEM WITH THE AIR CONDITIONER!  Sorry about the caps, but don't spin your wheels on something that obviously works.

I believe your RV has an energy management system that will limit which devices will work based on how much shore power or generator amps are available.  I think for some reason you energy management system thinks you don't have enough amps to run the 2nd compressor.

I would look at trying to find info about your energy management system.

If my assumption that your Adventurer doesn't have an energy management system, then I apologize for giving incorrect advice.

Here is a link to another forum with info about the power management system in Winnebagos.  http://www.winnieowners.com/forums/f263/why-is-intellitec-ems-load-shedding-351701.html

I realize the forum link I gave is for a 50amp RV, and is for a Winnebago Journey but the idea is the same and I believe the Journey has a energy management system similar to yours.

The following is a lengthy quote from the forum topic above:

Here's a quote from Understanding Your RV's "SHOREPOWER" :

? "This system is designed to prevent ?tripping? the circuit breaker at the pedestal/post if the RV user inadvertently turns on too much electrical equipment ? meaning the total amp draw will be greater than the rated level of the post?s circuit breaker.

The Intellitec 50 Amp Smart EMS? recognizes when electrical power is being supplied to the RV. Through its diagnostic programming, it can determine if the incoming power is 50 Amp power, 30 Amp power, or Generator power. If the incoming power is from a 20 Amp source, the RV user must identify this lower power level by pressing the ?30/20 Amp Select? switch on the display panel. The system cannot discern the difference between 30 Amp and 20 Amp power!

When functioning at 30 Amp (or lower) power, the system controls the ?On/Off? operation for a maximum of six electrical loads. These loads are typically ?heavy? loads (high amp draw) and their cumulative amp draw will trip the post?s breaker. Typical loads (in the order of lowest to highest priority) are the Electric Element in the Water Heater, the Rear Air Conditioner, possibly a Washer/ Dryer, and the Front Air Conditioner. (Other appliances may be attached to the system in larger RVs. However, the Microwave is controlled by the Inverter, if you have one.)

The system is also programmed with the ability to ?memorize? the amp draw of each electrical load (appliance) attached to it. The system "memorizes" and stores the amp draw for each controlled load only when it is 'shed' (turned off by the system). It subtracts the new total amp draw of the RV from the original total amp draw - the difference is the amp draw of the shed load.

The system continuously monitors the total amp draw. If it gets too high, the lowest priority appliance will be shed (turned off). If the amp draw continues to be too high (or goes higher), the next lowest priority load(s) will be shed until the total amp draw is below the power limit of 30 or 20 Amps. This means that, no matter what order you turn appliances on, the Water Heater will always be shed first, then the Rear Air Conditioner, etc. The Front Air Conditioner is the last load to be shed. This is all done in the interest of protecting the RV from excessive amp draw.

When a load is shed, the appropriate ?Power Status? light on the display panel may blink for the first two minutes. This indicates a time delay to protect an air conditioner?s compressor. Once the time delay is completed, and there is enough power available to operate the load, the light will turn on and the appliance will be restarted. If there isn?t enough power available, the light will turn off and the appliance will remain off until adequate power is available.

When plugged into a lower level power supply or running the generator, the RV?s total amp draw is displayed in a two digit ?Load Meter? window on the display panel. It behooves each RV user to check the existing amp draw before turning on more equipment.

NOTE: The load shedding capability on a 50 Amp Smart EMS? is automatically deactivated (turned off) if 50 Amp power is being supplied to the RV. Remember: Load shedding only occurs if a 50 Amp system is ?dogged? (adapted) down to a lower power source (30 Amp or 20 Amp), or operating on Generator power. This means, when the RV is attached to a 50 Amp power source, the 50 Amp ?Service Type? light on the display panel will be lit, as will all of the ?Power Status? lights (all loads able to operate), however, the ?Load Meter? will be blank. Because the load shedding is deactivated, there is no need for the system to monitor the total amp draw and does not do so.

So, my friends, when you are plugged into a 50 Amp power source, a blank ?Load Meter? does not mean the system is broken, but, instead, is working as designed!"

If you desire more technical detail, I recommend reading your Intellitec Manual very carefully. If you don't have one for your system, they are available at www.intellitec.com.




SarahW is on the mark. Highly recommend you go to http://www.intellitec.com/ and download the manual. You can also call them direct. They are very helpful. After unsuccessfully chasing a problem the last several days, that I was blaming on the EMS circuit board (replaced as previously noted) I called them this AM and they restored my confidence in the circuit board.

But first your issue. I took the liberty of pulling up your drawings and your original brochure https://winnebagoind.com/product-res...ct-information . Your Adventurer came std with a 5500W Onan @ 30amp. There was an option for a 7000W Onan @ 50amp. It appears that you do have a two stage compressor in your basement air. You should call Intellitec at 419-965-3014 and discuss your load shedding conundrum. BUT FIRST, look at your Onan and see which one you have, 5.5K or 7K, then look at your EMS display to see if you have a light for 50amp. Alongside the 20, 30, 50, Gen indicators will be a little screen that shows shedding order. As SarahW's excerpt describes, load shed is a 30 or 20amp function. Order of load shed is set at the factory, but the controlling dip switches on the (now infamous) circuit board can be reset at will (not likely smart). Armed with that information, when you speak to Intellitec, you should be able to ask pointed questions.

Since you asked about our latest go 'round with EMS,  it goes like this. We pulled in, shut down the CUMMINS, made up the shore power, surgegard indicated green to go on all legs. But not one panel lit up on the One Stop. I blamed the EMS. Looked at trouble shooting in the manual, two choices. Laid my multimeter across J4 pin 4 (L1) and pin 6 (L2), read 240vac+/-. Good! Tested J3 pin 1 and pin 8 for 12vdc. Squat! Was sure another failed circuit board. Called Intellitec. Was informed that 12vdc does not come out of the circuit board, it comes in from 12vdc system and out to ONLY the EMC indicator panel. But, usually the rest of One Stop feeds from the same source. Guy tells me to look for a popped 12vdc breaker. The front TV breaker was popped. Reset it. One Stop lit up for a few seconds, then the breaker popped. Dark again. Guy tells me to look for a short in the entertainment area. Guy says only Winnebago knows why they fed the One Stop panel through the TV breaker. (And only W knows why they read the 3rd leg of 50amp off the water heater breaker) So, I pulled the TV out of the way, inspected that rat's nest of wiring , found a wire chafed by a sharp metal edge, cut and butt spliced it, set the breaker, all is well. Until our next electrical adventure.

 

 

[mrd341]

thank's for the link, i will check it out asap, and yes i do have the ems. The parts that i was waiting for arrived today so i installed the new relay, capacitor, and hard start capacitor in the #2 circuit and this is where i'm at at present.
i am plugged into my home 20 amp breaker, (i can't run the generator until tomorrow when i get a chance to fill the tank as she is now down to a quarter tank so the gen shut down)
1. i set the thermostat to 10 degrees below current temp and slide to cool
2. the amps go to 20a for a second, i can hear the compressor #1 kick in and the amps settle in at a steady 11a and cool air comes out of the vents.
3 approximately 2 minutes later, the amps jump up to 20 again, i hear #2 comp kick in and the amps settles in at a steady 16a
4. out of curiosity, i shut the breaker for #2 off and immediately can hear the unit shut down and come back on again with #1 compressor steady at 12 amps with #2 breaker still off.
5. i reset #2 breaker and waited a few minutes then heard the unit bog down for a second and saw the amps steady at 17a

i don't understand how they could both be running and drawing the low amps
hopefully tomorrow, i will be able to test it again with the generator, see if anything changes and report the outcome, thank's for all the help!

 

[AStravelers]

thank's for the link, i will check it out asap, and yes i do have the ems. The parts that i was waiting for arrived today so i installed the new relay, capacitor, and hard start capacitor in the #2 circuit and this is where i'm at at present.
i am plugged into my home 20 amp breaker, (i can't run the generator until tomorrow when i get a chance to fill the tank as she is now down to a quarter tank so the gen shut down)
1. i set the thermostat to 10 degrees below current temp and slide to cool
2. the amps go to 20a for a second, i can hear the compressor #1 kick in and the amps settle in at a steady 11a and cool air comes out of the vents.
3 approximately 2 minutes later, the amps jump up to 20 again, i hear #2 comp kick in and the amps settles in at a steady 16a
4. out of curiosity, i shut the breaker for #2 off and immediately can hear the unit shut down and come back on again with #1 compressor steady at 12 amps with #2 breaker still off.
5. i reset #2 breaker and waited a few minutes then heard the unit bog down for a second and saw the amps steady at 17a

i don't understand how they could both be running and drawing the low amps
hopefully tomorrow, i will be able to test it again with the generator, see if anything changes and report the outcome, thank's for all the help!

I have a 2006 Winnebago 36G Journey with 50amp setup and my amp draw figures compare to yours.  About 2-3 amps higher but not that far off.  What I do see on my monitor is during the initial compressor startup, compressor #1 pulls about  20-23amps and then drops to the 13-14amps.  Compressor #2 makes the amp draw jump to 27-28amps before settling down to 19-22amps. 

My amp readings certainly are a lot lower than what I have repeatedly seen reported in forums.  Almost always the reporting of the amp draw is by people who have not actually monitored the amp draw on the panel in a Journey or Adventurer like you are and I have.  Most figures seem to be in the 26-28amps continuous with both compressors running.

Additionally since your rig is a 30amp, your A/C may be a little smaller BTU.  Just speculation, I have no specific info on the BTU rating. 

 

[mrd341]

thank's, I have not yet been able to get the rv gassed up yet to test it with the generator, but hope to before the weekend! In the meantime, i have been working on the infamous problem of trying to fix the hot water tank which would only work on propane and not electric! after much research, and "contortionism", i was finally able to locate and reset an overload switch on the back of the heater, which was probably the most difficult thing i have done on any motor vehicle to date!!!LOL
on another note, it has been a little chilly here lately, so i tried the heat pump aspect of the a/c and it appears to be working properly on 20 amp shore power and it sounds like the compressors are working ok on heat.

 

[AStravelers]

thank's for the link, i will check it out asap, and yes i do have the ems. The parts that i was waiting for arrived today so i installed the new relay, capacitor, and hard start capacitor in the #2 circuit and this is where i'm at at present.
i am plugged into my home 20 amp breaker, (i can't run the generator until tomorrow when i get a chance to fill the tank as she is now down to a quarter tank so the gen shut down)
1. i set the thermostat to 10 degrees below current temp and slide to cool
2. the amps go to 20a for a second, i can hear the compressor #1 kick in and the amps settle in at a steady 11a and cool air comes out of the vents.
3 approximately 2 minutes later, the amps jump up to 20 again, i hear #2 comp kick in and the amps settles in at a steady 16a
4. out of curiosity, i shut the breaker for #2 off and immediately can hear the unit shut down and come back on again with #1 compressor steady at 12 amps with #2 breaker still off.
5. i reset #2 breaker and waited a few minutes then heard the unit bog down for a second and saw the amps steady at 17a

i don't understand how they could both be running and drawing the low amps
hopefully tomorrow, i will be able to test it again with the generator, see if anything changes and report the outcome, thank's for all the help!

Another example of low amp readings for the basement A/C.

Yesterday, I needed to exercise my generator.  The inside and outside temps were in the low 70's and my initial amp draw readings were right on the mark that you had. 

11-12 amps for compressor #1 and a total of about 16-17amps when compressor #2 kicked in.  When I came back about 30 minutes later to shut down the generator, the reading was 18-19 amps total.

 

[mrd341]

well, i am still scratching my head over this! i finally had the opportunity to get gas today and started the generator when i got home,then slid the thermostat over to cool. with the in room temp at 82 and the thermostat set to 70. with the generator running it is difficult to hear the compressors kick on but i did notice the amps go up to 20a for a second then settle down to to 12a. a couple of minutes later the amps went up to 16 for a few minutes and then settled down to 14 and stayed there for the next 2 hours. the coach cooled down to 74 degrees in that time. i measured the temp with a non contact infrared meter and the temp at the a/c intake was 74 and the temp coming out of the ceiling vents was 60 degrees. while i was reading posts about the basement a/c, some of them said that there should be a difference of 20 degrees with 1 compressor running and a difference somewhere around 30 degrees with both running, that, coupled with what seems to be a low amp draw which makes me think that maybe the second compressor is not running. sorry for all the confusion, i just bought this rv last month and am trying to make absolute sure that everything is working as it should before we head south in a couple of months for our first long adventure (2 months). we've never owned an rv before and i am finding out that the previous owner was a "little" deceptive with me by hiding a few non working items that i am finding as go along thanks for all the help!

 

[mrd341]

i have been reading a lot of material on the coach systems and am beginning to think that maybe it is an ems problem that i have. i started the generator today and turned the a/c on. i heard the compressor kick on and the amps settled at 14, then i heard the 2nd one kick on (or at least try to) then the amps actually went down to 11a on the display and stayed there for  a couple of hours but the temperature in the coach is going down nicely from 87 degrees to 80 at present in the last 2 hours and the temp coming out of the ceiling vents is 62! which seems to indicate that it is working ok?