Front A/C

[ugh]

quote:Originally posted by Ozz

Get the 15,000 BTU unit, I like Dometic, and bought the unit for our bedroom soon after we bought the 2007 3400RL. It comes with a kit to install. I am a HVAC Tech, but this is a 'no brainier' for an average Joe. The only difficult part is getting it on the roof. I had a neighbor with a Bobcat (small skid-steer tractor) raise it to the roof and my wife and I installed it, just read the directions and follow them. I would not worry about the height just like Jim Fischer noted. The main power is in a box in the cavity where the unit sits, just attach the black to black, white to white and green to green,or copper wire to copper wire. (With the power off) I don't remember if I had to add a 20 amp breaker or not) it nmay already be there.
As for the thermostat wire, I didn't have any there, we just turn on the unit with the knobs on the unit, works fine with us.
With the 15K unit, we often turn it on high cool, blow the air downstairs and leave the living room unit off if it isn't too hot. When it gets hot, you will be glad you have two 15K units. Get the big one. Only about $100 difference. Any questions email me. hvac.repairs@yahoo.com

What model number do you recommend?

[Ozz]

I sell A/C units, but not Dometic, so this should show I really like them
This one: http://www.rvpartscountry.com/DometicDuoThermBriskAir15000BTURVAirConditionerTop Unit.html
Now, I am not really up on the ducted systems, so anyone familiar with them jump in here, but you have a 2006 model, so your unit can't be too much different than mine.
I did some ducting and register mods, I will find it and post the how-to.

[ugh]

quote:Originally posted by Ozz

I sell A/C units, but not Dometic, so this should show I really like them
This one: http://www.rvpartscountry.com/DometicDuoThermBriskAir15000BTURVAirConditionerTop Unit.html
Now, I am not really up on the ducted systems, so anyone familiar with them jump in here, but you have a 2006 model, so your unit can't be too much different than mine.
I did some ducting and register mods, I will find it and post the how-to.

I am not going to worry about the duct work. I will use it as a stand alone unit and control it by the knobs.

[Ozz]

As you can see by the link, it is on sale, a very good buy.
Here is my ducting Mod, it really helped the airflow from my living room unit. I recommend all of the steps, but if you just trim the diffusers and add the dampered covers, it will help.
https://picasaweb.google.com/Jimsue13/20110618ACVentModificationAndAdditionalAdded?authu ser=0&authkey=Gv1sRgCMf1o6Tmpa2IQA&feat=directlink

Ozz

[Alwims]

Do the mod that Ozz posted and I promise you, you'll be glad you did. Really made a big difference in our rig. Since we have the rear kitchen model it might make a difference, but we discovered, this spring by accident, that we get better air flow though out the rig if we leave the ceiling fan off. We've got 2 vents that it seemed to disrupt. We've done informal testing and the temps in here, at ground level, are 5-6 degrees cooler with the fan off. Just to clarify, our rear air is ducted and our front air is not.

[Ozz]

You will need to buy the ceiling assembly as well.
(Thanks Alan)

[grayghost03]

I agree with Ozz, the low profile is 9" the standard Dometic is 12.7". The Dometc as given us great performance.

[Ozz]

One of the reasons to buy something for your RV is service availability, there are far more Dometics out there than any other brand. If you need service in the field, or across the country, odds are, more RV service techs have laid hands on the Dometic than any other brand, you odds are greatly improved on getting a satisfactory repair job. Parts availability are drastically improved as well. You have to look at the big picture when you buy something.
Service on anything in the field is scary, why increase the odds of getting something fixed wrong.
JMHO, but an opinion with a degree of experience..
Dang, sounds like I work for Dometic, Nope.
John's post on the profile is a good one, remember that the unit is on a slope, so the increase in height does not raise the clearance that much.

[trlrboy]

We put a 2nd 15K unit in the front of ours when we bought it. Ours is a ducted system which makes a big difference. When you are watching TV at night in the living area you can turn off that unit and the one in the bedroom will still push cool air to the back of the trailer. The same reasoning works at night when you go to bed. You'll be able to run the back A/C and it will cool the bedroom. Makes for quiet TV viewing and sleeping. Then in the heat of the day you run both at the same time. Works great for us.

[ugh]

quote:Originally posted by Ozz

As you can see by the link, it is on sale, a very good buy.
Here is my ducting Mod, it really helped the airflow from my living room unit. I recommend all of the steps, but if you just trim the diffusers and add the dampered covers, it will help.
https://picasaweb.google.com/Jimsue13/20110618ACVentModificationAndAdditionalAdded?authu ser=0&authkey=Gv1sRgCMf1o6Tmpa2IQA&feat=directlink

Ozz

If I understood correctly by looking at the pictures, there is no pipe like materials running in the ceiling from rear A/C to all vents. The air is traveled between the lower ceiling and the upper ceiling and exit through the vents? Correct?

[Ozz]

No, on ours (my 07 and your 06) there is a fiber-board duct that runs from back to front.
Then it exits from the vents or diffusers.
Ozz

[sreigle]

We found that one A/C worked fine up to about 92 or 93F. At that point it would keep the coach at about 78 but would slowly work up to 80. After that, pretty much every additional degreee outside increased inside temperatures. If it's 100 outside it's going to be probably 83 to 85 inside depending on window shade positioning, etc. If it hits 110 outside it's probably going to be about 90 inside.

After experiencing that a few times we added the second A/C. Now if it's 110 outside it will maintain under 80 inside. Not by a lot, though. If we're in shade, then, of course, it stays cooler inside.

One thing to keep in mind... if you are connected to 30 amp, that second a/c may or may not run without popping a breaker, depending on what else is running on electricity (120v or 12v). With 50 amp, we can run both A/C units and the washer. Or the dryer. But not all four. So on laundry days we run just one AC. Sometiems we have gotten away with running all four but usually not.

[Clemson1881]

A big factor in cooling is not only temperature but humidity as well. In the South or near a coastline mid to upper 80s will overwhelm one A/C. The evaporator fins will get soaked with condensation in these conditions and the units cooling ability will diminish big time.

[Art-n-Marge]

I have to agree with Steve Reigle's numbers that over mid 90's the one A/C barely cuts it and this is with drier climates like the lower half of California, Nevada or Arizona. We've RVed in 100-107 degree temps and the 1 A/C did not do very well, at all. To get relief during the day, we used the down vents of the A/C (diverted from the ducting) and stayed mostly in the living room (we closed off the BR) and it was tough... when we started getting too hot, we took a short walk in the extreme heat so when we returned the cooler 85 - 90 temp in the rig seemed much cooler and drank as many cold drinks as we could.

Since we don't go out as much as most, we can pick our location's weather so we don't do this to ourselves any more. When we get that second A/C, we won't worry about it so much. Unfortunately, our wish list is so long.

[Alwims]

I got to thinking about all this and went up on the roof to look at our front and rear air. Took the covers off and wow were they dirty. Grabbed my little pressure washer and went to town cleaning the fins and everything that didn't look like it would electrocute me. You can't believe the difference in temp inside here. I don't think either one of our airs has blown this cold before.

It's not very hot today, only 86, but I don't think the compressors have ever cycled good like they are now. I turned the stat down to 65 and I thought the DW was going to kill me as I was making so much fun of her all bundled up in the comforter off the bed. Wish I'd have thought to clean them a long time ago. BTW, our front air is a 15,000 BTU. Just needed a good cleaning.