Air Conditioning System

[raphaman]

Hi All
I'm a Newbee. I just bought a 2006 Monaco Diplomate 400 diesel with 53,000 miles on it. I drove it 500 miles and had 3 stops a various RV parks. Everything went pretty well. I'm learning a new language.

Here is my question. I tried to run the air conditioning just using the generator and I can't seem to get the air to run. I ran the generator for two hours today to charge things up hoping that would give it what it needed. I had just cleaned the batteries and everything looks good. I plugged it into 120 and the air ran fine. It just doesn't run off just the generator.

 

I could really use some help:)

 

John Nielsen

[Guest THE TRAILERKING]

Check the breaker at the generator....

[Star Dreamer]

If you are referring to your roof top ac unit, it does not use battery juice to run so topping off the batteries doesn't help the ac to work. Also check your transfer switch to make sure it is working. Do you have ac power to any outlets when your generator is running?

[Kirk W]

I do hope that the new language you are learning doesn't include too many swear words!

 

On the problems running the a/c from your generator, there are a few things you can easily check. With the shore power not connected, start your generator and once running check the 120V-ac wall outlets to see if they have any power. You can do that with a volt meter, one of the outlet testing devices from a home store, or just by plugging a lamp into one of two and see if the lamp will turn on. If there is power to those outlets, next test to see if the a/c will operate.

 

If the outlets do not have power either, then it means that the problem could be the circuit breaker on the generator set or it might be the automatic transfer device(ATS). Normally an ATS is set up to shift to the generator output if both it and shore power are available, so never start the generator when the a/c or other major loads are in use as that will damage the contacts. If you look on the side of your generator set, there should be either one or possibly two circuit breakers. The number will depend upon the size of generator and location depends upon make and model of generator.

[raphaman]

Thanks for the input. I just ran the generator again and checked AC outlets. All worked and were producing juice except two in the bedroom. The bathroom outlet worked but the test/reset button doesn't work. All lights and pumps work.

 

Kirk, you mentioned about not running the generator while shore power is operating and air is operating. I wasn't aware of that and I have done that on a couple of occasions. (Newbee mistake?) The inverter was working OK but the register panel said battery was juice was fare.

 

I'm I hearing that the generator should run air without any problem on its own. (I hope so). What do I do now. All you help is invaluable!!

 

John

[raphaman]

Also I'm hearing the label Transfer Switch. What is that and where is it located. How do I determine if it defective etc.

 

Thanks John

[coachmac9]

Welcome to the forums! I am fairly new also so I am going to step aside and let the folks that have been doing it a lot longer and are wayyyy more RV savy than I am do the talking...don't get discouraged and be sure to read all the other forums that are available...you will learn tons of stuff if you do!! Welcome aboard!!

[Star Dreamer]

Also I'm hearing the label Transfer Switch. What is that and where is it located. How do I determine if it defective etc.

 

Thanks John

The transfer is box similar to this one:

 

http://m.campingworld.com/browse/skus/index.cfm?skunum=67274&rewrote&affiliateid=5193&gclid=CM2y-azsx8gCFQmPaQodHlwLwQ

 

It is typically located right after where your shore power wires come into the coach and is where your generator wires tie into the power feed. Be careful as it may/will have power in it if your hooked up to shore power or running your generator.

 

You will have to test the input and output at the transfer switch with a meter to see if is working properly.

 

We never use our generator to feed power to the trailer while hooked up to shore power. In fact it is impossible in our case as we deleted our transfer switch as they have a bad habit of causing fires (ours also was not working) and we simply plug our shore cord into an outlet in our generator bay that is powered from the generator. In our case, we have to go to our generator to start it so it is not a big inconvenience.

Dave

[Pat & Pete]

The transfer is box similar to this one:

 

http://m.campingworld.com/browse/skus/index.cfm?skunum=67274&rewrote&affiliateid=5193&gclid=CM2y-azsx8gCFQmPaQodHlwLwQ

 

transfer switch as they have a bad habit of causing fires

Dave

Seriously ? I've not heard or read anything about that . Please expound .

 

And , I don't mean to jack the thread , but ...

[bruce t]

Just because you have ac in your power outlets while the generator is running doesn't mean that that is where the power is coming from! AC can easily be coming from your batteries via the inverter.

You should have a power management control panel. Check the settings. It is possible that the previous owner had settings that don't suit what you are trying to achieve. Also are you trying to run all the a/c units at once? That may exceed what the generator can handle.

 

If all else fails kick the cat and go to a dealer. Yeah they may laugh but it will save some gray hairs.

 

Good luck.

[Star Dreamer]

Pat & Pete, the issue with transfer switches appears that the lugs loosen up and need to be checked on occasion. If they loosen up too much they start arcing and can overheat the wires and start a fire. Our switch was not in an easy place to get at to be able to check it out on a repetitive basis so it was better to just eliminate it.

 

Back to your regular scheduled forum posting!

Dave

[Pat & Pete]

Pat & Pete, the issue with transfer switches appears that the lugs loosen up and need to be checked on occasion. If they loosen up too much they start arcing and can overheat the wires and start a fire. Our switch was not in an easy place to get at to be able to check it out on a repetitive basis so it was better to just eliminate it.

 

Back to your regular scheduled forum posting!

Dave

 

Makes sense . And , now that you mention it , I do recall something about checking for loosened connections there . Thanks for the reminder . I have something to do tomorrow .

 

And , Putting that info out there again sure won't hurt anyone's rig .

[FULLTIMEWANABE]

Hi John, we don't know much about much, but we've just come back from a 6 week trip and found that our generator when we put it on to run the 2 x AC units (not noticed any issues in the past!) kept tripping and hubby had to go out and reset several times on the genny, didn't seem to be an issue when running just one, then realised when we checked the generator book that it was being overloaded when we put on say the toaster or a kettle forgetting the AC was on, but even so the generator wasn't running right on just the two AC/s or even one at times, which added together appeared to be just below the max draw for the generator. At one point the AC was draining our battery bank as we couldn't hear the generator had stalled, albeit the units on the controller were on the red shedding lights.

 

Anyway's long story short, she is 13 years old has 671 hours on her, and we aren't sure what was done to her when we sent her in for a service every so often over the years gone by. Our experience of paying others to do things on our RV over the years have been far from comforting, shall we say!

 

We've just come back from spending C$130 at Cummins Onan Parts on inline fuel filters, spark plugs, new piece of hose (see crack in current one appearing), 2 quarts of 15W 40, clips, air cleaner filter and so on. Haven't a clue what we're doing but we're determined to learn how to service and do more and more on our RV ourself to know what has and hasn't been done. We are hoping that is the issue, but we are also going to take the domes off the roof AC's and clean the coils. Hopefully this is all that is needed, but if the air also doesn't blow cooler we made need to recharge the Freon we think (worry about that when we get to that stage)

 

Also, not being hands on DIY types in the past, we didn't know that there was an altitude adjuster on our Onan 5500 Marquis Gold that we should change according to whether we are sea level or up on the Canadian Rockies during operation = another Ah Ha moment for us.

 

Not knowing how well the previous owners looked after the generator or when it was last thoroughly serviced and parts replaced as per the advisory hours for replacement etc, you may want to consider having her given a thorough service John, as well check the coils etc are clean on the AC units themselves.

 

FTW.

 

PS: Just a thought have you checked the oil level in it? If it gets ridiculously low can affect the pressure I believe???

[Kirk W]

. I just ran the generator again and checked AC outlets. All worked and were producing juice except two in the bedroom.

 

Kirk, you mentioned about not running the generator while shore power is operating and air is operating. I wasn't aware of that and I have done that on a couple of occasions. (Newbee mistake?) The inverter was working OK but the register panel said battery was juice was fare.

Since you clearly do not understand RV electrical systems, I'll address each of your statements individually.

If you had your generator running and the shore power cable was not plugged into anything, but you did have 120V-ac to anything at all, that tells us that the generator is putting out 120V-ac and it also demonstrates that the "transfer switch"(or ATS) is doing it's job. If it were not, there would be no possible way for power to get from the generator to the electrical distribution panel. Have you looked at your 120V power distribution panel? I would suggest that with all major loads turned off, you to the the distribution panel and open, then close each one of the circuit breakers. It is difficult to impossible to look at one and know if it has tripped as the switch handle moves very little when one trips. You need to do that first in order to be sure that none of them are open.

 

The bathroom outlet worked but the test/reset button doesn't work.

This is a separate issue as the outlet is probably a GFI outlet and it may well control other outlets, but is unrelated to the original issue you posted about. If could well be that it is controlling the outlets in the bedroom which do not work, and that it does need to be reset, but I strongly suggest that we leave this problem and only deal with one issue at a time. If you can plug a lamp into this outlet and it works, either with your generator running and/or with the shore power connected, then leave it be for now and lets address that after we find the answer for your main problem.

 

All lights and pumps work.

Your lights and water pump operate from 12V-dc power that is supplied by the RV battery and/or the converter which uses 120V-ac power to "convert" that into 12V-dc power to recharge your batteries and to supply the RV's lights, water pump, as well as the furnace, refrigerator, and water heater control circuitry. Those appliances operate from 12V-dc & propane to allow you to use them when not connected to any source of 120V-ac power like your house uses.

 

 

I'm I hearing that the generator should run air without any problem on its own. (I hope so). What do I do now.

While we do not know what the size of your generator set is, but it is pretty safe to state that your generator has plenty of power to operate the roof air conditioner(s). You don't say what size your Diplomat is, but most of them have two roof air conditioners and the generators are nearly always sized to be able to operate both at the same time.

 

 

Also I'm hearing the label Transfer Switch. What is that and where is it located. How do I determine if it defective etc.

The term "transfer switch" or ATS or any of several others commonly used in the RV world, means a device that is installed into most modern RVs that come with an on-board generator set to select between the power source of the generator or the shore power cord. These devices have two inputs, one permanently wired from the generator and the other the RV side of the shore power cord and that device selects one of those to and connects it to the 120V power distribution panel to supply everything inside of the RV. If only one has power, it will automatically choose the one with power but if you have 120V from the shore power cable and then start the generator set, the device will automatically shift from the shore power supply to the generator set. To do that with heavy loads like the air conditioner operating is very hard on the device as well as on anything that happens to be powered at the time so that is what I was cautioning you about. Doing that with an air conditioner running is one of the main causes of one of these ATS devices to fail.

 

We never use our generator to feed power to the trailer while hooked up to shore power. In fact it is impossible in our case as we deleted our transfer switch as they have a bad habit of causing fires (ours also was not working) and we simply plug our shore cord into an outlet in our generator bay that is powered from the generator. In our case, we have to go to our generator to start it so it is not a big inconvenience. Dave

Since you are not the first owner of your RV, it is possible that yours does not have any ATS or transfer switch, as it could have been removed as Dave's had or even a few didn't have one at all. There is a hint that you don't have such a device in that usually an RV which doesn't have one will have a power plug to fit the shore power cord located in the area where that cord is stored. But in your case, you have stated that you do have some 120V inside with your generator running and the shore power not connected, which tells me that you must have an ATS and that it is working.

 

I'll also make a comment about the use of one. When used properly these devices are very safe and in the years that I have been in an RV I have never heard of one fire that was caused by one. They do occasionally fail, but that too isn't very common if they are properly used.

 

Because you have some power when you run the generator, you must have a working transfer switch or ATS.

[raphaman]

Thank you very much Kirt...this really helped me to understand more fully. As I mentioned I'm going to have a Norco refrigerator re-call kit installed on thursday and I hope to get all these electrical things explained and taken care of so I can move on to the next fase of newbee ville

 

Johnny come lately

[Dutch_12078]

If it's been mentioned, I missed it, but check that any breakers on the generator are fully on. You mentioned that a couple of outlets don't work while the others do, and that may be an indicator that one of the generator breakers is tripped. If you have two A/C's, one may work, but not the other in that case.

[bruce t]

Kirk you need to keep in mind that the generator mat not be supplying the 120v to the outlets. It may be coming via the inverter. So it is possible for the generator to be running but no power is getting to the rv for whatever reason.

Be careful with inverters. An rv sitting with no shore power and a silent generator can still have 120v in the outlets.

 

Simple non technical test!! Disconnect any shore power. Start the generator. Then while the generator is running turn on your microwave oven. If your generator is 'working' correctly you should hear it load up when the microwave oven comes on. If it doesn't then my guess is that you have a problem that a dealer should be able to diagnose.

 

regards

[Jimalberta]

I too look at my lcd display on my microwave to tell me when the gen has started to produce power and the power has started to come through the transfer switch ( I usually keep my inverter off) . Keep in mind that it takes a while for the gen to start producing power....its not instanteous. Mine generally takes about 30 seconds after the gen engine has started until it starts producing power.

[Kirk W]

Kirk you need to keep in mind that the generator mat not be supplying the 120v to the outlets. It may be coming via the inverter. So it is possible for the generator to be running but no power is getting to the rv for whatever reason.

Be careful with inverters. An rv sitting with no shore power and a silent generator can still have 120v in the outlets.

That is true if, you have 120V with no generator running and no power plugged in from the outside. But if there is no 120V to the outlets without the cord plugged in and you do get it once the generator has started, then it must have come from somewhere.

 

Johnny come lately, what they are saying is true that if your coach has an inverter, which it quite possibly may, then you need to be extra careful as it is fairly common for an RV to have only some outlets that are supplied by the inverter and others which are not. That is particularly true for outlets that are on a circuit with the TV sets. But outlets supplied from an inverter will also have power with neither the generator running or the shore power connected. Test is to have outlets that loose power without shore power and then gain it when the generator starts. It is possible that you may be seeing power from an inverter, so be careful.

[bruce t]

Kirk the point of my point is not to exclude other possibilities. Inverters have bitten more than one RVer.

Forums are great place for information. However a novice 'playing' with high voltage is a bit of a worry. I hate the stuff. My suggestion, due to the many variables, is to take it to an RV dealer and have them diagnose the issue.

 

regards

[raphaman]

Hi John, we don't know much about much, but we've just come back from a 6 week trip and found that our generator when we put it on to run the 2 x AC units (not noticed any issues in the past!) kept tripping and hubby had to go out and reset several times on the genny, didn't seem to be an issue when running just one, then realised when we checked the generator book that it was being overloaded when we put on say the toaster or a kettle forgetting the AC was on, but even so the generator wasn't running right on just the two AC/s or even one at times, which added together appeared to be just below the max draw for the generator. At one point the AC was draining our battery bank as we couldn't hear the generator had stalled, albeit the units on the controller were on the red shedding lights.

 

Anyway's long story short, she is 13 years old has 671 hours on her, and we aren't sure what was done to her when we sent her in for a service every so often over the years gone by. Our experience of paying others to do things on our RV over the years have been far from comforting, shall we say!

 

We've just come back from spending C$130 at Cummins Onan Parts on inline fuel filters, spark plugs, new piece of hose (see crack in current one appearing), 2 quarts of 15W 40, clips, air cleaner filter and so on. Haven't a clue what we're doing but we're determined to learn how to service and do more and more on our RV ourself to know what has and hasn't been done. We are hoping that is the issue, but we are also going to take the domes off the roof AC's and clean the coils. Hopefully this is all that is needed, but if the air also doesn't blow cooler we made need to recharge the Freon we think (worry about that when we get to that stage)

 

Also, not being hands on DIY types in the past, we didn't know that there was an altitude adjuster on our Onan 5500 Marquis Gold that we should change according to whether we are sea level or up on the Canadian Rockies during operation = another Ah Ha moment for us.

 

Not knowing how well the previous owners looked after the generator or when it was last thoroughly serviced and parts replaced as per the advisory hours for replacement etc, you may want to consider having her given a thorough service John, as well check the coils etc are clean on the AC units themselves.

 

FTW.

 

PS: Just a thought have you checked the oil level in it? If it gets ridiculously low can affect the pressure I believe???

Thanks a lot for your thoughts advise. I'll let you know how it goes. John

[raphaman]

Hello Everyone

 

You guys helped so much to my overall education.... big time I was at the RV local tech's place and it was a simple fix. Generator works great and I got inverter educated. All of you contributed to my education. Kirk you broke it down........"I obviously don't know about electrical" you were so right. But the good news is I'm learning.

 

Thanks again

 

John

[Dutch_12078]

John, I'm glad that the problem got sorted out and wasn't serious. What did the solution turn out to be?

[G&K]

Just read the thread.

 

There is something that some people may not be aware of regarding Transfer Switches. The original Iota 50 amp transfer switch with the plastic case DID have fire issues.

 

I was alerted by my inverter guy in Kelowna this summer when we were working through another unrelated issue. My unit had one of the original, somewhat problematic ATS switches. As long as the connections are tight, you are fine. If they vibrate loose the case itself is flammable if you get it hot enough.

 

Reading further, apparently the original Iota company went out of business before issuing a recall notice, but many/several/some RV manufacturers have recalls for this ATS.

 

There is some pretty good reading to be found here:

http://www.irv2.com/forums/f115/iota-transfer-switch-smoke-tested-206308.html

 

Geo

[Kirk W]

Hello Everyone............................ But the good news is I'm learning.

And that is just how all of us began! We never learn everything but learning and sharing is the reason for these forums. Thanks for the update.