A/C Problem

[Openroad2010]

I have a 2010 Open Road 35QBA Ford Chassis. I am having a difficult time keeping the front of the coach cool. The rear air conditioner will cool it at just about any temperature we want. While the front one, which has the optional heat pump struggles to cool much under the low 90's. I have had this issue checked by Johnny Walker in Las Vegas twice now. They continue to tell me it is working fine. Resently it was at Johnny Walker's for 4 days and they left both front and rear A/C units on 24 hours a day and the front of the coach never got under 88 degrees. 88 degrees is what they told me. I requested that they leave the A/C on until I got there to at least see for the first time a temperature under the low 90's in the front of the coach. Much to my surprise it was unplugged with nothing running when I got there and the temperature was 99 degrees inside when I got there. Anyone else having similar problems?

[paz]

Openroad, welcome to iRV2.

We have a 37' Allegro Bay, and the front is usually a lot warmer than the back. The front is a bigger area. For another thing, there is a lot of heat coming in through the windshield, especially if parked or driving west or south in the hot sun. And if you're in Vegas, you are in the HOT sun.

Another issue with the Allegro is the absence of dual pane windows.

One way to check the AC is to measure the air temp coming directly from a vent as close as possible to the unit. Check the front vs. the back. If the temps close, then that's the best you're going to do. If the front is significantly warmer, then that unit may need to be recharged.

[jeepfreak]

I have the same issues and have to run both to do the job. If you go to the Tiffin owners forum this question is addressed although it's mostly the Bus owners. But it's caused by having one common duct running thru the ceiling for both A/C's. The common duct for the return I don't think is an issue. What some have done is to remove one of the supply grills and put in a pecut piece of foam to stop the front air from feeding the back. I don't know the size as I have not done it yet, but I think a call to Tiffin you could find out the size of the supply air duct. Hope this helps. Terry.

[okgc]

I took our Allegro RED to the dealer for an AC check last week. They could not find a problem.
On warm days the rear air running alone will do a much better job of cooling the whole coach than using the the front ac alone.

[Essex-Spensive]

Tiffin uses NO insulation on the front end. Look behind the cabinets and you will see nothing but the fiberglass cap. Some have insulated and found a huge temperture difference. good blinds will help when parked also. LV is over 100, it needs all the help it can get.

[TXiceman]

My suggestion is to make an insulated wrap fro the windshield and then insulate the cap area.

ken

[Openroad2010]

Thanks for all of your responses, anything else would be very helpful.
I have been thinking and working on this and have decided to try this today. I am cutting cardboard circles the size of the vents, then cut the circle in half so you can spin one half over the other half to open and close the opening, which will adjust the airflow. Somewhat similar to the vents in my home. I also put one of the cardboard pieces in two of the air return vent in the cooler section of the coach, thinking this may help pull air from the warmer section. With the air conditioning basically a closed system it should also slightly help pull the cool air into the warmer areas. I have done pretty well everything else including insulating the front cap months ago and also under the coach with high density foam board, which dramically lowered the road noise inside the coach. I also put blocks of foam right at the end of the last vent in the front of the coach both the cooling vent and the return air. There is 14 inches of dead space past those vents. The return is just pulling in extra heated air from the front cap, even though the duck work is sealed. The extra space past the cooling vent makes the air buffet and prevents a clean exit into the front of the coach. After doing just that you can feel the difference in the air pressure. Like I said I have giving this a lot of thought and am hoping I am getting some kind of handle on the hugh problem. I can not understand why it has to be 90 to 95 degrees in the front when it is only 100 degrees outside. Again thanks for your help. If you would like to personal contact me, I can be reached at Shelcort@hotmail.com or my home number is 702-658-8224
Thanks again Leonard Lewis

[jzick]

We have a 35' Allegro Bay. When the temperature is above 90 and we are in full sun (sitting) we found the front ac would struggle to keep up also. I found that putting a tower fan in the hall near the bathroom door to blow air from back to front made a huge difference. I guess what we are doing is using rear cool air to help in front. With full sun and temperature outside at 98 @ 3:00 in the afternoon, temperature in the front stayed at 74 until 4pm then rose one degree per hour until 7 pm, then started back down. Tower fans are about $30 at WM.

[Openroad2010]

Hello again,
This is Leonard Lewis, I have the 2010 open road with the front A/C cooling issue. The small cardboard circles cut the size of the ceiling vents and installed, did help move more of the cooler air from the back to the front of the coach. The foam blocks installed at the end of the duct work help some more. I closed one and a half vents off on both the supply and the return in the back of the coach. I have informed Tiffin and the A/C manufacturer what I found to be the main issue on my particular coach. I have always felt my main problem was the lack of supply and return air volume in the front. I finally took the A/C unit off the roof myself and looked under the unit. I looked at the supply and return openings on the A/C unit. Then made a template of the openings and laid the cardboard template on the supply box in the roof of the coach. I found that the supply and return were sharing a very small section of the box. Which would account for a small amount of the air flow issue. If the unit is pushing air and then drawing the air right back in, it will not go out the supply or be drawn in the return as much as it could from inside the coach. If this happens to MUCH, it can also freeze up the evaporater coil and the compressor will short cycle. Which will produce warmer air inside the coach than the A/C unit could be providing. I still thought that small amount of air sharing was a minor issue. So I took a piece of plexiglass and laid it over the box in the roof. I applied some pressure and found that the center gasket was not making contact well enough to completley separate the return and supply, hinch more air sharing. After seeing that, I then added a 1/2 thick foam gasket all the way across the divider. I then installed the A/C unit back on the coach, went in the coach and turned on just the fan. I do not have sufficient power where the coach is sitting to risk operating the A/C, I also do not have enough fuel in the coach to run the generator. I will be leaving in another week with the coach and will check things out, on how well it cools, not just moves air. I have had this issue for a year now, so another week won't hurt. THE BIG THING WAS, ONCE I RE-INSTALLED THE A/C UNIT AND TURNED ON THE FAN. I HAVE MORE AIR FLOW THAN I COULD HAVE EVER THOUGHT POSSIBLE. Prior to installing the extra thick gasket, I would put a piece of paper over the return vents in the front of the coach and the paper would immediatly fall and would not be sucked over the return vent. NOW when I take a piece of paper and get close to the vent, the paper is sucked up to the vent and stays up there. Again with the supply vents, prior to doing my work, there was not much air flow coming from the last two vent furthest from the A/C unit. NOW you can actually feel air flow when sitting in the passenger seat. I will let you know what happens in a couple weeks, but I think all should be well. The A/C manufacturer engineers have called and are very pleased with what I have found. I have also submitted a redesigned supply box to both Tiffin and A/C manufacturer.
I have to thank Richard at Tiffin Motor Homes for putting up with all my calls and his continued help and giving me the needed things to do what I needed to do.
Sorry for the short story!

[Openroad2010]

Hello OKGC,
You may want to look at doing what I did. After reading your post, you sound like you have very similar issues with the front A/C. You and I both know that Tiffin wouldn't let a motor home go out of production where using the front A/C unit didn't help cool the coach. I think what I submitted to them will be helping. The A/C manufacturer thinks they made a supply box change recently. Which may be the reason so many 2010 tiffin owners are having A/C issues with the front A/C. If an 8.5 X 11 piece of paper over the farthest return vent will not stay stuck over the vent, you may want to check that center gasket out.

Hope I could help.
Leonard Lewis
702-658-8224

[muleskinner]

Hello, I have a 2009 Allegro RED, and have had the same problem with the front area not cooling adequately. Incredibley, our output air vents could not be closed off, nor could they direct air flow. As a warranty issue, I asked that directional air flow grills with open and close capability be installed. Our dealer did this, and that helped a tremendously! I have also purchased from Lowes a roll of foil covered bubble wrap insulatin and made a front windshield cover for when we are stopped. I used some of the insulation that was left over to insulate the back of all the cabinets. All of the above has made a tremendous difference.

[sdemino]

Try this. turn on only the front A/C. Go to the rear of the Motorhome and see if Air is coming out the vents. If it is, the cool Air is all going to the rear of the motorhome. I had this issue in a 40 Phaeton. THe bedroom would be so cold and the air was not on back there. The A/C up front would run forever but never reach set temperature. All I did was by some A/C insulation for window A/C and place it in the A/C duct where I wanted the Front A/C to stop.

[gordons1]

A 2009 Phaeton Owner,Leonard Lewis in las Vegas (see above comments from Open Road) discovered an engineering design issue on the front ac unit. There is a 1-1.5" gap that prevents the Coleman roof unit when installed in the plenum to contact the half inch foam along the diagonal divider that separates the "supply" side from the "return". He noticed that when he held a flat piece of paper up to the return vent (in the ceiling) that it didn't suck it up like most returns will do!!

He then pulled his front a/c unit and cut a piece of plexiglass to match the shape of the a/c unit. When laying it in place, he saw the gap that I described above. This is similar to a bad heart valve! The warm air does get sucked out because the Unit is getting most of it's air from the supply side. Now, his rig cools off twice as fast and you can hold paper that literally gets sucked out of your hand when it's 4" from the return vent!

Wade, the tiffin service manager, fixed my 2007 phaeton this past Friday of this problem at no charge. The result was incredible - I now feel air moving in my coach. This is an easy fix. Lewis put it all in writing and sent it to Richard Blanton and Bob Tiffin. He was kind enough to send me a copy so it made it easy to describe this issue when I drove over to red bay. They will send you the 1" foam tape to let your service center to repair your coach.

[Doghauler]

Just happened to see this link, our Tiffin has the same issue! Glad to see there is hope for a fix. Thank you all for the research and look forward to a cooler summer! I will contact my dealer right after the Holiday's for that foam fix.