Coleman A/C not Cool

[kmpro]

We have a Coleman 13500 BTU a/c on our 1984 310 and like I have always thought, that's not enough cooling for a 31 footer. Shoreline runs front air only and that leaves us cooking. Not enough cool. Does anyone make a 15000 BTU with heat strip or heat pump that will fit my AS? i don't want to have condensate draining down the side of my m/h, so what a/c is the right choice???
Mike

[3 Dog Nite]

Maybe the AC just needs a recharge. We recharged our Coleman Super Machs 2 months ago for the 1st time since installation at the factory in 1989. I know this because a schrader valve needed to be installed. The older AC units were designed for repairs, not replacement like the newer models. Have a reputable AC servicer look at it before considering a replacement.

Ricky

[bkahler]

Originally Posted by kmpro

We have a Coleman 13500 BTU a/c on our 1984 310 and like I have always thought, that's not enough cooling for a 31 footer. Shoreline runs front air only and that leaves us cooking. Not enough cool. Does anyone make a 15000 BTU with heat strip or heat pump that will fit my AS? i don't want to have condensate draining down the side of my m/h, so what a/c is the right choice???
Mike

Mike,

It sounds like your 310 only has one A/C unit installed. Ours has one on the front and one on the rear. Although when connected to shore power only one unit can be ran at a time. On the rotary switch under the upper cabinet by the sink you should have a setting that reads front air and one that reads rear air. I'm guessing that Airstream ran wires for both air conditioners but the original owner of your MH opted not to purchase it. However you should be able to install an A/C unit in front no matter what.

The other thing that a lot of us have done is rewire the back A/C unit to run on a separate feed to shore power so you can run both at the same time. You'll find several posts on the subject if you search for posts by bkahler. Definitely a worth while modification if you have two A/C units.

Also while searching you'll find a bunch of wiring diagrams that I created after sorting out the wiring on our 1984 310.

Brad

[kmpro]

Brad:
I have two a/cs on my 310, but no rotary switch as you and others have mentioned. I have an A/C/Microwave switch above the stove. I can only run the front air on shore power, whereas I can run both on the Generator. I think I would like to wire in a second shore line for the rear air or redo the whole thing with 50 amp service and get it up to the 21st Century. Help me to know which is most practical as I am not poured in concrete on anything at this point. The real problem exists is not enough cooling on just one air.
Mike

[bkahler]

Originally Posted by kmpro

Brad:
I have two a/cs on my 310, but no rotary switch as you and others have mentioned. I have an A/C/Microwave switch above the stove. I can only run the front air on shore power, whereas I can run both on the Generator. I think I would like to wire in a second shore line for the rear air or redo the whole thing with 50 amp service and get it up to the 21st Century. Help me to know which is most practical as I am not poured in concrete on anything at this point. The real problem exists is not enough cooling on just one air.
Mike

Mike,

It will actually be simpler for you to wire for alternate shore power on the rear A/C compared to our 310.

All you need to do is modify the box where the generator ties into the rear A/C which is probably underneath the bottom fold down door under the RH closet. Somewhere in there should be a junction box where the wires coming from the generator and the rear A/C join.

If yours is what I'm guessing it is you could do something similar to what I did. You might try something like this:

You’ll need the following materials, about 3 feet of 12/2 romex cable, one metallic electrical box that holds a duplex receptacle, receptacle cover and one 3-prong male cord connector along with associated cable clamps for the metallic box.

1. Mount the metallic box just inside and on the floor of the lower compartment where the generator junction box is located.
2. Break the metal tab between the two sockets of the duplex receptacle. This isolates the two sockets from each other.
3. Pull the romex cable from the rear A/C unit out of the generator junction box. The Romex cable should be coming out of the RH wall of the coach above the wheel well.
4. Connect male 3-prong cord connector to the end of the Romex cable coming from the air conditioner.
5. Run the 3 foot section of romex cable from the generator junction box to the new metallic box and connect it to one of socket of the duplex outlet.
6. Connect the other end of this 3 foot romex in the generator junction box to the wires where the generator romex was originally connected too.
7. From inside the generator compartment (or any place you find suitable to have an extension cord feed into the motorhome) drill a hole large enough for a 12 gauge extension cord and strain relief to pass through. You will need to cut off the female end of the extension (you can discard this piece). The cut end of the extension cord also goes into the new metallic box and connects to the other socket on the duplex receptacle.

What you now have is a duplex receptacle that has each socket powered from a separate source, one source is the generator and the other source is an external extension cord that you would plug into a shore power outlet. The generator cable that now has the male plug on it is plugged into either the shore power socket or the generator socket that you just added.

This is how I did the wiring on my 310. Someday I would like to change the socket and plug arrangement to a nice switch but I haven’t taken the time to find a suitable 20 amp 2-pole switch.

If you want to talk about this send me a PM with your phone number and I'll give you a call.

Brad

[kmpro]

Thanks Brad for the much needed instruction on how to get my coach cool in the Texas heat. AS must have had their head up and locked when they rigged it this way. For sure I am going to make modifications like you did to eliminate the problem. Once again, many Thanks.
Mike

[bkahler]

Originally Posted by kmpro

Thanks Brad for the much needed instruction on how to get my coach cool in the Texas heat. AS must have had their head up and locked when they rigged it this way. For sure I am going to make modifications like you did to eliminate the problem. Once again, many Thanks.
Mike

Mike,

I'm curious as to whether your Motorhome has a transfer switch in the electrical compartment where the shore power cord connects to the motorhome. Also do you have any sort of transfer switch located in the compartment where the rear A/C connections are? I'm guessing that you don't have a transfer switch for the generator due to the fact your rotary switch under the cabinet doesn't have a selection for rear air.

At a minimum you should have 30 amp breaker located where the generator connects to your rear A/C.

Another question. Have you tried to run both A/C units from the generator at the same time and if so how well does it work and what generator do you have?

Brad

[kmpro]

Brad:
I have an Onan 6.5 KW gasoline generator which will carry both A/Cs when running. There is a changeover switch for going from shore to generator, too.
My carburetor on the generator will not carry both A/C s and the microwave at the same time, so I think some Berryman B-12 will cure that.
Mike

[bkahler]

Originally Posted by kmpro

Brad:
I have an Onan 6.5 KW gasoline generator which will carry both A/Cs when running. There is a changeover switch for going from shore to generator, too.
My carburetor on the generator will not carry both A/C s and the microwave at the same time, so I think some Berryman B-12 will cure that.
Mike

Mike,

It sounds like your Onan is in a lot better shape than my Kohler unit is. I think I have a weak regulator, unfortunately replacement regulators are not cheap .

Brad