AC not as cold as I think it should be

[Stevej72]

Still testing out me new Grand Design Momentum 31G before taking our first trip. I turned the AC on about 2 hours ago and set it to 75 degrees. The temp in the trailer at that time was 85 and the outside temp is 87. In that 2 hours it has only went down to 80 degrees in the trailer. Sticking a thermometer in the vent shows air coming out at 59 degrees. Should it get cooler than that? Not sure what would happen if it were really hot outside.
Thanks Steve

[xrated]

If an A/C unit has a 20 degree differential between the return air at the point of entering the A/C unit, and the outlet air at the output of the unit, it is working well. Output air temperature is dependent on the temperature of the return air coming into it. So as the temperature of the room cools down, the output air will also be cooler that when previously tested.....that is the 20 degree temperature differential that you should be seeing. And I said 20 degrees differential; a good rule of thumb would be 18-20 degrees.

[The_Lovells]

If your Mometum 31G just has a single AC, it will be very difficult to get the temperatures you want in a poorly insulated box. Our 297rsts, about the same size as your TT,. has 2 15K AC`s that work hard on a humid 95 degree day to keep our poorly insulated box at 76 degrees. Closing blinds and finding shaded sites helps a lot.

[geotex1]

As @xrated pointed out, your air conditioning is working well! In fact, surpasses the spec for both Dometic and Coleman differential @xrated's differential is better than the manufacturers' service specs). Step back a take the perspective of letting your sticks and bricks equilbrate to that mid-80s ambient air temperature. A central air conditioning unit would we working hard to bring that down 10 degrees too. The units don't have rapid cooling capability like automotive air conditioners. If you have just a single unit, you will find it a struggle on hot and humid trips.

[huntindog]

If possible, get a head start on the day by running the AC at night.... In fact crank it down as low as it will go all night, and day. This will help compensate for the increased heat gain that will occur in the daytime.

[Stevej72]

Thank you all for your help, this answers my question perfectly! I'll leave the AC on as much as possible and probably add a second AC next year.

If an A/C unit has a 20 degree differential between the return air at the point of entering the A/C unit, and the outlet air at the output of the unit, it is working well. Output air temperature is dependent on the temperature of the return air coming into it. So as the temperature of the room cools down, the output air will also be cooler that when previously tested.....that is the 20 degree temperature differential that you should be seeing. And I said 20 degrees differential; a good rule of thumb would be 18-20 degrees.

If your Mometum 31G just has a single AC, it will be very difficult to get the temperatures you want in a poorly insulated box. Our 297rsts, about the same size as your TT,. has 2 15K AC`s that work hard on a humid 95 degree day to keep our poorly insulated box at 76 degrees. Closing blinds and finding shaded sites helps a lot.

As @xrated pointed out, your air conditioning is working well! In fact, surpasses the spec for both Dometic and Coleman differential @xrated's differential is better than the manufacturers' service specs). Step back a take the perspective of letting your sticks and bricks equilbrate to that mid-80s ambient air temperature. A central air conditioning unit would we working hard to bring that down 10 degrees too. The units don't have rapid cooling capability like automotive air conditioners. If you have just a single unit, you will find it a struggle on hot and humid trips.

If possible, get a head start on the day by running the AC at night.... In fact crank it down as low as it will go all night, and day. This will help compensate for the increased heat gain that will occur in the daytime.

[huntindog]

Thank you all for your help, this answers my question perfectly! I'll leave the AC on as much as possible and probably add a second AC next year.

Do you have 30 amp or 50 amp service?
With 50 it is easy. With 30, it may be possible to run 2 ACs, but not always so easy. It can most likely be done though, there are a variety of ways to do it. If you have 30, that is a whole nother thread to discuss/ debate the solution that would work for you

[Stevej72]

Do you have 30 amp or 50 amp service?
With 50 it is easy. With 30, it may be possible to run 2 ACs, but not always so easy. It can most likely be done though, there are a variety of ways to do it. If you have 30, that is a whole nother thread to discuss/ debate the solution that would work for you

Unfortunately I only have 30 amp. I didn't do enough research prior to buying. Ultimately will probably lose a lot of money to get what works for us.

[WhittleBurner]

Unfortunately I only have 30 amp. I didn't do enough research prior to buying. Ultimately will probably lose a lot of money to get what works for us.

It may be more economical to switch over to a 50 amp converter, plug and cord than to trade in over a 2nd AC if you are hapy with your trailer otherwise.
Then adding a 2nd AC would require electrical run to the vent if it isn't set up for it.

[openrangeowners]

Get Micro-Air Easy Starts for your AC units if you are adding a 2nd AC unit. I can run both my 15K AC units on 30amps with no problems. Each unit consumes about 1500 watts or 12 amps running. I can also run 2ACs on my 3000 watt inverter when supplemented with my Honda 2200 watt inverter. Did a couple of Harvest Hosts like this and it worked well. Of course I run the fridge and Hot Water Heater on propane when on 30 amps.