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RoscoeV
06-29-2018, 07:43 AM
I'm looking to install a second AC unit in my Laredo 325RL and have a few questions. My primary AC unit is a Coleman-Mach, should I add the same brand for consistency or does it even matter?

Second question - Since I'm adding the unit to the front of the 5ver (bedroom), should I look at a low profile unit which are ~8in tall or does the extra 4 inches in the standard units make a difference?

Thanks!

tech740
06-29-2018, 07:48 AM
I just added a second unit to mine in the front also. My opinion is that the brand doesn’t matter unless one is more reliable than the other. As far as the height I would think if you are not concerned about hitting things(close to 13’6”) I wouldn’t worry about that either. Low profile probably won’t add to your aerodynamics with a 5er in tow. Just my thoughts.

RoscoeV
06-29-2018, 07:59 AM
Thanks Tech, What model did you install? The Dometic Brisk Air II seems to be less expensive than others and the reviews look pretty good. I'll have to measure my overall height tomorrow.

Movin' on
06-29-2018, 09:18 AM
I added a Dometic Penguin II (I think that's correct, it's been a couple years ago). It's a low profile, 13.5 btu, that matched the factory ac. We have been very pleased with it. I was concerned with the overall height, that's why I chose the low profile.

tech740
06-29-2018, 10:34 AM
We did a domestic duo therm. It was a used unit off my parents old not home that was being turned into a demolition derby vehicle. I am still only 12’6” even without low profile so I had no worries.

Badbart56
06-29-2018, 12:30 PM
Last year I was looking to add another unit to my Toy Hauler and ran across PPL RV Parts out of Texas. I wasn't particularly looking for the same unit but they just so happened to have some "scratch and dent" A/C's and made me an incredible price on two Coleman Mach III's of the 15000 variety. As you might expect, I was concerned as to the extent of the "scratch and dent" damage. The only issue was that the covers on both units had some minor warpage. And honestly. I believe that has gone away since they have been exposed to a little Florida heat and sunshine! Still had the 2 year warranty. I've had them in service full time since last November without a hiccup. And having three units, it is nice that they match!

RoscoeV
06-29-2018, 01:03 PM
Last year I was looking to add another unit to my Toy Hauler and ran across PPL RV Parts out of Texas. I wasn't particularly looking for the same unit but they just so happened to have some "scratch and dent" A/C's and made me an incredible price on two Coleman Mach III's of the 15000 variety. As you might expect, I was concerned as to the extent of the "scratch and dent" damage. The only issue was that the covers on both units had some minor warpage. And honestly. I believe that has gone away since they have been exposed to a little Florida heat and sunshine! Still had the 2 year warranty. I've had them in service full time since last November without a hiccup. And having three units, it is nice that they match!

Thanks, I'll have to check them out.

wiredgeorge
06-29-2018, 01:07 PM
PPLmotorhomes.com is the largest consigner of RVs on the planet. Their parts department is well stocked and they ship fast. Bought a Brisk II 15K BTU yesterday AM and it was delivered today FREE. They don't have the absolute lowest price but are close and have free shipping and are legit. Find a place that has lower prices and then go look them up on the BBB. PPLmotorhomes is in Houston and has other lots in New Braunfels and Cleburne but their parts store is Houston.

RoscoeV
06-29-2018, 01:39 PM
PPLmotorhomes.com is the largest consigner of RVs on the planet. Their parts department is well stocked and they ship fast. Bought a Brisk II 15K BTU yesterday AM and it was delivered today FREE. They don't have the absolute lowest price but are close and have free shipping and are legit. Find a place that has lower prices and then go look them up on the BBB. PPLmotorhomes is in Houston and has other lots in New Braunfels and Cleburne but their parts store is Houston.

Thanks George, good information.

slufoot733
07-05-2018, 06:49 PM
Roscoe, a suggestion if I may. I suspect your A/C unit is controlled by a wall mounted thermostat. Many units are pre-wired for that second A/C unit, i.e. the thermostat can control both units.
When I had a second unit installed I told the tech to NOT connect it to the thermostat, to just set it up to be controlled independently with the knobs that come with it. That way, IF the thermostat malfunctions you can at least run the second unit without the thermostat. A friend had two A/C units and the thermostat failed. Both units were down, and he roasted all week.
Just a thought.

RoscoeV
07-06-2018, 05:09 AM
Slufoot,

I ordered the Brisk Air II and it should be here on the 12th. I plan on installing it on the weekend of the 28th while my son is visiting (I'll let him carry it up the ladder). It's supposed to be pre-wired and has the support bracket in place. Since it's going in the bedroom I don't think it's necessary to connect to the thermostat. We will just turn it on when needed to cool down the bedroom prior to going to bed. That's a good point about having a backup in case the thermostat craps out, I didn't think about that.

xrated
07-06-2018, 01:33 PM
All this talk about adding a second A/C unit drove me over the edge. After our last outing a couple of weeks ago, trying to cool the entire 35' Toy Hauler just was too much for the 15K unit that came with the trailer. We used to close the door between the living area and the garage, as mostly it's just Peggy and I. Well now that we have our little puppy and we are using the garage area for his crate and where he sleeps, that door is almost always open and the A/C just wasn't keeping up during the afternoons. So, I started looking around and after the suggestion about PPL Motorhomes, I found a Dometic Brisk II for a great price. My setup will be a non-ducted and I'm going to use a wall mounted thermostat since the A/C unit will be pretty far back in the garage....And almost impossible to reach the controls with out using a step stool, even when the sofa and bed is raised up. So the work will soon begin as I will get it week after next as the black wall thermostat was out of stock and will have to be ordered. Everything ships free, and that's a bonus.....Houston to Maryville, TN.

Pull Toy
07-06-2018, 02:19 PM
IMHO.... match the existing unit with the appropriate "Low Profile" for the front bedroom... Pure ascetics, and RESALE!

When you go to sell, try to look like factory!... "OH, MY, it must be too hot in there... they had to add an EXTRA A/C...!!! Make it look like "Genuine Factory"!

They're all good, or they wouldn't still be selling stuff, and they're all about the same price!

"The cheapest thing on a camper, is the Guy/Gal that's driving it!!"

Good Luck

14george
07-06-2018, 03:48 PM
Just added a second ac matches the other one. I agree with Pull Toy

DocP
07-07-2018, 02:12 AM
I just added a second Dometic Brisk Air II to the bedroom, and it makes a world of difference. I went with the 15,000 model. It is loud, but tolerable. I used my Little Giant ladder to push it up to the roof (one leg at 90 degrees and the other long leg at about 45 degrees). Once to the roofline, it was easy to flip it up on top. The toughest part of the install was scraping all of the old caulk in the roof from the vent that came out

xrated
07-07-2018, 02:38 AM
I just added a second Dometic Brisk Air II to the bedroom, and it makes a world of difference. I went with the 15,000 model. It is loud, but tolerable. I used my Little Giant ladder to push it up to the roof (one leg at 90 degrees and the other long leg at about 45 degrees). Once to the roofline, it was easy to flip it up on top. The toughest part of the install was scraping all of the old caulk in the roof from the vent that came out

I took a vent off of a 7' x 16' enclosed trailer that I had and put an A/C unit there back in 2012, and you're right...getting all that caulk off was a major pain in the posterior area. I've got that to look forward to again.

This time, since I've got a carport for the Toy Hauler, I'm going to rig a rope hoist that I have to the cross bracing in carport roof area, pull the trailer out from under it, place the A/C unit on the rope hoist and hoist it up....then back the trailer under it and lower it down onto the roof. The rope hoist is a 4 to 1 reduction, so I should only be "pulling about 25 lbs up.

Pull Toy
07-07-2018, 03:39 AM
One thing we haven't mentioned, regardless of brand name, is important to note. Once you've horsed the A/C up a ladder onto the roof, let it "rest" in a level position for at least two hours before testing it. This gives the Freon time to drain back to where it belongs in the system.

Good Luck,

RoscoeV
07-07-2018, 08:24 AM
One thing we haven't mentioned, regardless of brand name, is important to note. Once you've horsed the A/C up a ladder onto the roof, let it "rest" in a level position for at least two hours before testing it. This gives the Freon time to drain back to where it belongs in the system.

Good Luck,




Good point, thanks! Another question; Are these air conditioners as finicky as refrigerators as far as how level they have to be without damaging the unit?


Thanks

xrated
07-07-2018, 09:04 AM
One thing we haven't mentioned, regardless of brand name, is important to note. Once you've horsed the A/C up a ladder onto the roof, let it "rest" in a level position for at least two hours before testing it. This gives the Freon time to drain back to where it belongs in the system.

Good Luck,

You are basically correct....except that it's the oil that is in the refrigerant that needs to be allowed to drain. A compressor cannot compress a liquid...like the oil is....but it can compress a gas....which the freon is as it returns to the low side of the compressor.

xrated
07-07-2018, 09:06 AM
Good point, thanks! Another question; Are these air conditioners as finicky as refrigerators as far as how level they have to be without damaging the unit?


Thanks

No they aren't!

Frank G
07-07-2018, 02:59 PM
When the factory installs the second AC in the bed room of the 325RL it is the 13,500 BTU model, There is a separate thermostat on the bathroom wall and it is ducted in the raceway duct system. It will be interesting to see if you have access to these ducts. We use the low setting on the BR AC to do dehumidification duty with lower outside temperatures and high humidity conditions. You know' those 75 deg days with 95% humidity in Florida.

RoscoeV
07-07-2018, 03:31 PM
Frank, I'll know when I pull the air vent but I'm pretty sure the duct is blocked at the vent. The duct work does go to the bathroom from the bedroom with the current bedroom duct work. I popped the vents down and put foam insulation in the ducts that went past the vents that pushed air to the ceiling. I'm not too concerned about adding a thermostat, I'm adding a non-ducted ADB.

ht40
07-07-2018, 04:23 PM
I too was going to add a second A/C to the bedroom. I was wondering if there was any advantage to tying into the ducted system. Does anyone have any experience with the bedroom A/C unit only cooling the bedroom and not spilling cool air into the rest of the trailer.

Dan

14george
07-07-2018, 05:29 PM
I had a second ac unit installed in bedroom non ducked helped cool rest of trailer mines not a fifth wheel.

Frank G
07-07-2018, 06:11 PM
Lets specifically talk about the Laredo fifth wheel units. To this day they continue to use the "Race Track" AC duct system. Forgive me if you are aware of this system and how it works. :hide: I do not know how many other models use this system, I know the FR Cedar Creak line uses it.

Below is a link
https://www.keystonerv.com/media/2281/laredo-2016.pdf

The system is described on page 11. After 2016 it appears Keystone quit providing construction details in there literature, go figure. :facepalm:

The reasoning behind this post is, in the long run you will be much happier if you have a ducted system, and let the "Race Track" system work as designed. It is a good system. I have no idea as what the factory does when they do not install the second AC. The dealer we purchased from sells about (5) 325RL a year and all have the 2 AC from the factory.

johnlewis
07-12-2018, 08:17 AM
I have a friend who installed one of the low headroom units, and he said the noise inside is a lot loader with the low headroom unit.

I have bought a couple of things from PPL that were on sale (better prices than I found anywhere else), and I have been completely satisfied with their communication after the order, and the speed of delivery. Either watch for a sale on PPL, or call them and tell them the price you have found elsewhere, and see if they will match it.

goldtrigger
07-12-2018, 12:01 PM
In Texas we have to have 2 airs. I ran in to an issue with my bedroom air. Initially we had a 13K Coleman un-ducted on the bedroom of our 2011 Montana Mountanaire. In 100+ degree heat-high humidity, the two AC's would not cool the rig below 90 degrees.

Additionally, the front air would develop condensation on the down plenum when run on low speed/high cool at night and drip beaucoup water on the bed. This did not make me or the DW happy at all about 0200 when this happened.

When I had the second roof replaced after my second collision with a tree, the repair shop somehow broke the front air, which their insurance agreed to replace at no charge. I decided to fork over the difference for a low profile 15K Coleman unit.

Through experimentation, we have learned we can run the front air on max with a small fan from the bedroom door blowing air into the main body of the rig and cool the rig down to low 80's no matter what the outside temp. At night, we run the front air on low cool, half speed and it keeps the bedroom and rig cool and the plenum dry, no drip and DW and me happy!:)

PopBeavers
07-17-2018, 12:32 PM
I am replacing my tall a/c unit with an ultra low (8.5 inch). This will drop my height from 14 feet to 13 feet 7 inches.

14 feet is legal west of the Mississippi, except for Oklahoma. We are planning a 1.5 year trip to points east of the Mississippi next spring. The maximum height allowed east of the Mississippi is 13 feet 6 inches. I have no way to lower it another inch.

louielouieohoh
07-17-2018, 04:27 PM
I am replacing my tall a/c unit with an ultra low (8.5 inch). This will drop my height from 14 feet to 13 feet 7 inches.

14 feet is legal west of the Mississippi, except for Oklahoma. We are planning a 1.5 year trip to points east of the Mississippi next spring. The maximum height allowed east of the Mississippi is 13 feet 6 inches. I have no way to lower it another inch.

@PopBeavers; I'm pretty sure you only need to meet the requirements for ANY vehicle in the state where it is licensed.

I know that some states require brakes on trailers based on different weight classifications etc. A law enforcement officer cannot hold you accountable for a state where you do not live.

Can others chime in on this?

travelin texans
07-17-2018, 05:32 PM
If I'm not mistaken 13'6" is not the max you can be, but rather the minimum an overpass/bridge can be before "low clearance" must be posted by the state.
Most rv manufacturers build them at slightly over 13' then you may add vent covers or satellite dishes that may put you at about 13'6", unless you've added suspension lifts or other modifications I've never heard of a rv at 14'.

sourdough
07-17-2018, 05:51 PM
@PopBeavers; I'm pretty sure you only need to meet the requirements for ANY vehicle in the state where it is licensed.

I know that some states require brakes on trailers based on different weight classifications etc. A law enforcement officer cannot hold you accountable for a state where you do not live.

Can others chime in on this?

Various states can't dispute your driving license from your home state, but, any/all regulations relating to size, length, height etc. are enforceable in the state you are in....that's why you need to KNOW where you are going and what the laws are if you are in any way questionable.....just like gun laws.

As far as 13'6" regulations, here is the link to what the TX DPS says:

What's the maximum height for my vehicle?
The Texas Transportation Code specifies that the maximum height of a vehicle and its load may not be higher than 14 feet (View code) Transportation code, chapter 621, section 621.207).

PopBeavers
07-19-2018, 07:57 AM
If I'm not mistaken 13'6" is not the max you can be, but rather the minimum an overpass/bridge can be before "low clearance" must be posted by the state.
Most rv manufacturers build them at slightly over 13' then you may add vent covers or satellite dishes that may put you at about 13'6", unless you've added suspension lifts or other modifications I've never heard of a rv at 14'.

Tall a/c unit with a 4 inch lift.

boxcar
07-24-2018, 10:37 AM
OK, the posters in this thread has convinced me to get a matching black Dometic Penguin II low profile for my Sprinter 2nd A/C - thanks!

For a couple hundred extra I can get a heat pump option, which I expect will require a new thermostat. While I believe it would be good to have the extra heater that comes with it up front I've never owned a heat pump.

Any comments for or against?

My current stock A/C would only lower the temperature inside to 89 degrees when it was 93 outside - still under warranty so I'm taking it in as soon as I can get the appointment. The outlet was 64 degrees so I'm sure it's ductwork. We're going to be camping in Palisade CO in August with expect 100+ temperatures so I need to get this right!

Thanks,

xrated
07-24-2018, 11:08 AM
OK, the posters in this thread has convinced me to get a matching black Dometic Penguin II low profile for my Sprinter 2nd A/C - thanks!

For a couple hundred extra I can get a heat pump option, which I expect will require a new thermostat. While I believe it would be good to have the extra heater that comes with it up front I've never owned a heat pump.

Any comments for or against?

My current stock A/C would only lower the temperature inside to 89 degrees when it was 93 outside - still under warranty so I'm taking it in as soon as I can get the appointment. The outlet was 64 degrees so I'm sure it's ductwork. We're going to be camping in Palisade CO in August with expect 100+ temperatures so I need to get this right!

Thanks,

Something is wrong with your numbers there! An A/C unit, if it's working well, is normally showing an 18-20 degree difference between the inlet air and the outlet air. You are showing 25 degrees difference. What I suspect is that some of the outlet air is getting sucked right back into the inlet or return because of faulty ductwork or an air leak inside the unit. In other words, not all of the outlet air is being pushed out the ductwork through the registers/outlets......it is just recycling through the A/C unit....going in a circle. Getting that issue resolved would be my first priority, then see how well the unit cools the trailer on hot days

boxcar
07-24-2018, 11:14 AM
I agree with your analysis completely xrated, but after reading everything here I'm adding a second unit in addition to getting the problem fixed - just need to decide which model. We'll be using this camper in some 110 degree weather eventually.

I have an appointment with a Keystone shop to get the ducting fixed before this goes off warranty.

travelin texans
07-24-2018, 12:36 PM
The heat pump would be a great option, especially if you're somewhere that doesn't get extremely cold, they only work with the outside at about 38 degrees or more, lower than that it will blow cool/cold air.
One of our acs has the heat pump & works great.

boxcar
07-24-2018, 01:37 PM
Thanks, Danny. The cold weather camping I do is normally well below 40 and closer to 0, so I'll save the money!

xrated
07-24-2018, 03:30 PM
If Dometic is like the Coleman Mach ??? that I had on a previous trailer, don't bother with the heat strip either. Mine produced a little heat, but in my opinion you would be better off with an aux. freestanding heater that you could place where ever you wanted to put it. My T.H. has a 35,000 BTU furnace in it and it does a great job heating the trailer, but if we camped in cold weather, I would also buy/have an additional free standing heater for it.

boxcar
07-25-2018, 05:04 AM
That's another good tip, xrated, and will save some money. As long as I have ground power a standalone heater makes sense. We had a problem with the thermostat in the old camper one night when it was below freezing and a freestanding saved us - have to move that to the Sprinter before it gets cold.

I'm sure air flow is going to make a big difference and everyone should read this thread if they haven't:

http://www.keystoneforums.com/forums/showthread.php?t=25849

xrated
07-29-2018, 09:05 AM
UPDATE......Well, the new Dometic Brisk II 13.5K BTU is done. The hard part was getting all the sealant for the existing vent off without damaging the TPO roof. I used a rope hoist to lift the unit up in the air and backed the trailer under it and let it down. I completed the install this morning and fired it up to test the unit. I got a 20-21 degree difference between inlet air and outlet air which is about as good as it gets. There should be absolutely no problem cooking the entire trailer now.

mets721
07-31-2018, 05:48 AM
I’m looking to get the Dometic Penguin II for my 2016 Cougar 327Res 5th. It says it’s wired for it already and camping world said they can’t tie it into the system. What does that mean? Should it be ducted into the existing system or non-ducted stand alone for the bedroom?

louielouieohoh
07-31-2018, 06:06 AM
My local Keystone dealer says my 326RDS is stand alone in the bedroom if I want it installed. Controls would be on the unit (no thermostat on the wall) and no vent tie in. I pulled the vent off and verified there is no connection to the duct system. I suggest a quick look might verify for yourself as RVs differ in types of AC systems.

sourdough
07-31-2018, 07:27 AM
I’m looking to get the Dometic Penguin II for my 2016 Cougar 327Res 5th. It says it’s wired for it already and camping world said they can’t tie it into the system. What does that mean? Should it be ducted into the existing system or non-ducted stand alone for the bedroom?

Our bedroom is non ducted as well. I installed the Penguin II on ours (13,500) with the manual controls and love it. We had manual controls on ACs for many years so they just come natural to us and I like the AC for the bedroom because we like to sleep pretty cold.

If it gets really hot and the 15k seems like it might need some help we just turn on the bedroom, open the door, put a fan on the end of the chest of drawers and direct the cold air into the living area; works great. The Penguin II has vents around the shroud to blow air around in all directions or a dump feature where you push the slide back and the cold air just comes out one large opening. We have enjoyed ours.