2nd A/C to MK33 & finding a fellow mk33 owner

[stevenrees]

I noticed that our front room was significantly warmer than the rest of the coach when we camped in 85* weather last weekend. We live in Texas and I am VERY warm blooded, I am concerned about camping in the texas summers with only one A/C.

Has anybody out there added a 2nd A/C ubit to their coach? What would it take to do the job correctly?

I have a Onan 4000 generator, and my coach is wired for a 2nd unit.

Beside replacing the Onan with a larger unit, what else would I have to do?

I have 30amp service now.

Please give a detailed explanation, so I can figure out how much money I need to do the job.



Thank You for any help



Also, I would appreciate very much hearing from someone who owns a similar toy hauler so we are talking apples to apples and oranges to oranges. although I do appreciate the help from other RV-ers, It can (and does) get very confusing when it is a different floor plan and layout.

thanks steve rees

[hhh]

With 30 amp service you will only ever be able to run one AC unit at a time. You would have to rewire the rig for 50 amp service or run a separate 30 amp circuit just for the 2nd AC.

[stevenrees]

what would rewiring the coach entail? or cost??

[hhh]

While I am not an expert on it, I have read it is not all that difficult or expensive to do if all you want to do is run your AC off of half the 50 amp service. With 50 amp service you actually two separate 110v 50 amp circuits (50 amp service actually provides 100 amps split between two 50 amp circuits). One of them could power your present electrical panel, thesecond could power the 2nd AC unit. Since you are already wired for the 2nd AC I would suspect the wiring from that AC is already run to the present panel which would solve a major problem of getting power to the 2nd AC unit.

If you are just looking to power the 2nd AC unit you would need a new 50 amp power cord, the 50 amp plug (replacing your current 30 amp plug) for the side of the rig and a new breaker box with 20 amp breaker installed for the 2nd leg of the 50 amp service. Your 2nd AC would then be hooked to this new breaker box. If I had to guess it should be able to be done for well under a grand.

From there, if you wanted, you could put ina couple 15 amp breakers in the new breaker box and install a couple 110v outlets to power some other items like an electric heater or electric appliances. This would releave the load off the main 30 amp circuits you now have.








Edited by: hhh

[Hunter11]

If you don't want to go to the trouble and expense of rewiring your unit for 50 amp a dedicated 20 amp circuit will run a second 13.5k AC unit which should be plenty if you already have a 15k AC unit.It is tough to get by on a single AC unit here in Texas in the Summer.

[Sirsea]

We have a CF335SS and just had a second unit installed this week. For the record, both units WILL run on a 30 Amp connection if you don't run anything else such as water heater, microwave or refrigerator. Our unit had been running 5 hours on a 30 Amp service when we picked it up.Outside temp was 91, inside temp was 67.....



We had two options for a second unit. First was a 13.5 K with controls mounted on the face of the unit and manually adjusted for temperature, but the fan runs constantly. We ordered the upgraded unit which is wired into the existing thermostat and controlled as Zone 2 and operates the same as the main A/C. The installed price for the first option was $916 incl tax. The second option was $1,200 and change and took a little over a week to order and install.

[hhh]

Or just spend the extra $500 or so and upgrade to 50 amp service so you can actually use the trailer. IMHO, not being able to use anything other then the AC is not an option. I'd rather have the trailer at 80 degrees with one AC and be able to cook, watch TV or use the microwave then just sit in an icebox and look at the walls.

[mbinohio]

I agree with hhh, to have a unit and not be able to use anything just to me makes no sense, I think in this day and age to have a unit with 30amp service is like a house with 100 amp, fine for the basics but not much else, I think the smart thing is to upgrade to 50 amp, at this point what's 500.00, and then do your 2nd A/C. I have 50 amp in mine but my unit came with one A/C, it's almost 38' and with 4 slides one wasn't enough, they wanted to put an A/C unit in with the controls on the unit, I told them no way, I wasn't going to have cold air blow directly on the bed, I bought the unit that was tied directly into the duct work, looks just like the main unit and I did the 15K instead of the smaller unit, not that much different in price, and I did not buy the low boy unit, I have the exact same unit on the front and back, the trailer is now 13'4 tall and so far the height has never caused a problem, the bedroom A/C unit is on a seperate thermostat and it's in the bedroom, my camper is too old to have the newer type thermostat, I had the A/C unit put on when the camper was new and it's worked like a charm ever since, but I thin the smartest move for you is to switch to 50 amp so you can enjoy all the toys you paid so dearly to have.....enjoy your camper

[we-canoe]

Steve, I BELIEVE that the 4000 onan should run both AC units as my parents had a Class A with 2 roof AC units and 30amp shore power,only 1 would run plugged in but BOTH would run on the 4000 onan. Do the race tracks have power or will you be on gen power that might help on the 50 amp .

[John B]

I too very much like the 50 route & if you are going to use it heavily you might seriously consider that way but if not. There is a device but the name escapes me now that rotates the A/Cs,one will run to a point and cycle of & then the other takes over but as sai I can't remember the name of the device.The thinking is that each area is cooled to a level directly & then each unit does ot's thing plus sharing the other section some too but keeps the amperage draw down to a decent level. If the name comes to me I will forward it! ImHO jb.

[stevenrees]

I am not very trained with electrical , All I know, is that I don't know---ya know

I was told by the seller that my mk33 is prepped and wired for a 2nd A/C unit.

On the side of my trailer, there is a sticker that states 30amp service.

He also gave me two adapters that are marked 50amp to 30amp. (pigtail style).

One is male to female, and the other is female to male.

I do not understand what these do, Does it reduce 50 amp from the pole to 30 amp at the trailer?

Or does it put 50 amps to the trailer, through my 30amp cord?

I am getting frustrated with the manufacture.

I purchased what I was told was a "detailed service manual" for $20, what I received was a generic manual the covers all 2008 units.

I guess I am going to have to take it to a dealer, all I want to know is what I need to do to install a 2nd A/C unit.---no that is a lie, I want to know all I can to maintain and repair my trailer.

Any or all help would be appreciated, I need some detailed info covering my mk33 5fth wheel toy hauler.

Doed anybody else have a similer trailer? Or can you tell me where I can get a "detailed service manual" Or possibly a electrical & mechanical print for my unit?

I am planning a two week trip this June to colorado, and I would really like to have a much better understanding of how my coach is built;



Thanks for all the posts so far-- and thank you in advance for any that are coming.



steve rees 817-683-9596

[hhh]

The Onan 4000 will be borderline. My Yamaha 2400 barely starts my 15K A/C unit. Once it is started the amp draw is much less so as long as both A/Cs are not trying to start at the same time you should be OK. Very few manufacturers have a detailed service manual. At most you get an envelope full of paperwork that contains the manuals for each major installed item. The manual that came with my Cruiser is much better then the one (none at all) that I got with my previous Flagstaff.






Edited by: hhh

[stevenrees]

If there are no service manuals, then how do the authorized repair shops know how to trouble shoot problems in new (never offered before) trailers?

I don't mean to be difficult, but I do not believe that there are absolutely no service manuals for these 35,000 to 150,000 dollar trailers.

Somebody somewhere has to know where there is a bluprint or manual for my coach---I am less than happy with the manufactures help I have recieved.

I feel like If I do not want to take it to a dealer for $110 /hr, then OH WELL your on your own.

I did a lot of research before buying, and I heard nothing but praise for crossroads cust service---I'm not feeling very warm & fuzzy about it now!

steve

[cwit]

There is no service manual, And you may not be wired for a second air. Sorry

[dalemac377]

Iagree with most folks that the best move is to go to the 50 amp. service. Having had a couple of units with 30 amp. service and now one with 50 amp. service, there is no comparison. I would also suggest u call Randy Mischler at Crossroads service and ask him for help with the info you are looking for. If anyone at crossroads will help, he is the man.

[John B]

Most certified repairs agencies are quiet well versed on many brands & in many cases the similarities are huge.
I would advise you to get a good general learning on fifth wheel trailers in general from any source plus get in & under to learn & understand what is going on as most of us have.The reason being most units are built with the same supplied pieces just assembled a little differently
You are going to catch flack from a few if you lob boulders of generalities at Crossorads service people because many of us repeat customers and long timers know better that that.
Remember asmy folks told me you get back what you give out so be nice and lay out a professional outline and ask if some one might be able to help me with a problem I am having.
If you are having a difficulty determining if you are provisioned for a second A/C,normally look at the roof vents from the insidewithout the A/c & if there is an electrical box cover on the ceiling near the opening generally that vent is wired for an additional A/C. Good luck & if all else failscall Randy and be patient but he can assist you when he is available!

[wsc01q]

stevenrees





First; I am a licensed electrical engineer.

Second; with 2 AC units, you want 50 amp service, you'll have a better camping experience

Third; never use an adapter to plug a 30 amp "anything" into a 50 amp circuit unless you want a nice fire. I've seen it done, but it's not safe.

Forth; It is not hard to upgrade to 50 amps although I find it hard to believe that your unit is wired for 2 AC units and does not have 50 amp service. You can check the breaker panel in the trailer which will have 2 50-amp linked breakers for 50 amp service.

Finally; I just ditched my 50 amp power cable and bought one with a 30 amp plug that connects to my 50 amp service. BUT I will/can only plug into 30 amps at the campground, will never add a 2nd AC unit, hate messing with the big clutzy heavy50 amp cable, and prefer to add more insulation if my camper gets too warm.

[John B]

To try to answer your electrical question , the cord that is hooked to your trailer > If the cord has 3 prongs, 2 flat & one round you have 30 amp service!!! If the cord has 4 prongs, 3 flat & one round you have 50 amp service.
30 amp is one hot, one neutral & one ground, 120 volts from hot to ground or to neutral!
50 amp is one red 120 volt,one black 120 volt, one white neutral,one bare or green ground.
240 volts across the two hots or 120 volts from one hot leg to ground or neutral.
The adaptors allow you to geta30 amp leg from a 50 amp receptacles it dead ends one 50 amp leg so just 120 volts.
Your rig would have a 30 main so that will eliminate any over amperage in the coach.They can also allow a 30 amp recept to be split to 2- 30 amp legs feddown the 50 amp wires to the unit.
Good luck & be careful! Jb

[wsc01q]

Do not try anything thatgets "a 30 amp leg from a 50 amp receptical". You are only protected for 30 amps at the main inside the camper but watch what happens when, say, the campground lawn mower slices your 30 amp power cable (has happened) or you get a short anywhereinside the camper on the feed side of thethe power panel where the 30 amp breaker is. A 30 amp power panel itself will not handle 50 amps on it's connections. Don't do it.

[stevenrees]

I apologize for offending anyone, I truly did not meanto.

If you go back to my first post, and follow along to this last post, you will see that I have asked for assistance concerning my mk33. I received alot of info from different people--and I very much appreciate each and every one AND any future posts wiil be appreciated as well.

I am a first time rv owner, and I bought a very nice coach (toy hauler) for $27,000. in cash that my wife and I saved for quite a while for. I researched toy haulers and bought what I thought was the best deal.

Our first outing was at a MX track with no elect, and the generator quit after less than 10 min. I call our local C/R dealer (Vought in Ft Worth TX) and was told they do not service generators. My next casll was to a local mobile repair , who promptly screwed me out of $395.00. I next went to a Cummings / conan repair--( $200.0) who got it running but it also quit after I got it home. I then went to United RV in FT Worth who replaced the fuel pump/fitler/ pick up/ 30' fuel hose, to the tune of $1200.00.

My generator is now running fine and I am happy with my purchase again, although I am sure you can relate that it was a bumpy start.

I have not talked with Randy, but I will put in a patient call. I am confident he can help.

My dissatisfaction was with the service manual that I asked for. I paid $20 and was specific about my request!! That I wanted a SERVVICE manual. What I recieved was a very nice owners manual which does not answer my questions.

I just want to better understand how my electronics work and what I need to do to ( MY SPECIFIC COACH) to accomodate a 2nd A/C as well as tank placement/ water heater bypass valve etc. I want to know where these parts are BEFORE I tear into it

Which is why I asked more that once if anybody else owned a mk33.

I do understand that most coaches have similar parts located in different places--I just do not have a point of reference do to my inexperience and lack of a print/manual.

So please do not stop posting, I am reading ( and saving ) every one.

My coach is stored in a storage unit( that does not allow repair work)several miles from my home, and I do not have room to work on it at home except in the street in front of the house. So I just do not have the luxury of working on it for an unlimited time. I need to get in--fix it--and get out. Hence the request for a service manual/blueprint.

Again, please accept my apology.

Please keep posting--I am learning from every one



thanks

steve