AC air flow problem SOLVED

[Uncle Rog]

Tankie, I had CW install the second unit, $600 less than the dealer!, and yes the wiring was in the roof, as advertised. The only issue was the length of bolt they needed because the BH, with the extra insulation and aluminum super structure, was thicker than most RV's. I opted for the standard 13.5k unit, in retrospect, they offer a 10a unit that I was too impatient to wait for as we were leaving to a hot area and the timely delivery of the energy saver was in question. With the 10a unit both could be used on a 30a supply........................Dumb...........

 

[MMToo]

It Really Works

Just to let you know, this is my first post.
I've known about this owners forum since shortly after we bought our 3055BH a year ago March. I hadn't joined till now as I was afraid I'd wind up get expelled for to much venting (no pun intended here). I think our rig was in for work about eight months for warranty work. True a lot of that was over the winter when there was no rush. I will say here that Heartland and K&C RV really worked with us and we are now pretty pleased.
However twice when the rig was in for work on of the items on the list was lack of AC air from the vents. The first fix resulted in no change. Except for the bathroom being unnecessarily cold there was no discernible air from the vents. After the second it was discernible but totally inadequate. The AC unit would freeze up after some hours if I didn't keep the dump vent all the way open. So the AC finally made it to the top of the list. 95 to 100 outside and 85 inside just wasn't cutting it. So to see the pictures and drawings I finally registered. Thanks timk and Jim for your pictures and drawing. About two hours work and I now have real AC. There were some other ideas I also used. I think I completely separated the input and output which probably was a major contributer to the freeze up. I used some leftover cold air return material from when we remodeled the house. It is basically a corrugated cardboard with heavy foil on each face. I made the tent and closed of about half of the dump area so I can still use it if I want. Before the fix the AC ran all the time. Since the fix it has even cycled a few times. We are pleased. Thanks to all the contributers.
None

 

[jbeletti]

MMToo,

Welcome and congratulations on your first post. I am pleased to hear that you guys are pretty pleased at this time.

Happy camping,

Jim

 

[BobSue]

work on AC

Well I spent several hours Saturday looking through my AC unit.

We had what I consider fair air flow and managed to get through some hot weather but I thought it could be better.

I opened up the AC unit and found that it had been seal fairly well. There was a nice piece of foam separating the inlet/outlet. A few small leaks were easily covered with foil tape. I did trim some rubber closer to the wood to reduce things in the air stream.

I then went through all the vent outlets and found them fairly well sealed up for a production job. But I went through each of them and made sure they were well sealed.

I did find that the duct work going forward and rearward went well beyond the last vent outlet. They appeared to have been taped over from the outside during construction, but as much as several feet beyond the last outlet. I didn't trust their tape job so I plugged the duct and sealed it up. This is one place that would be easy to miss during construction and would be hard to diagnose. If not closed up, most of the air would disappear between the roof and ceiling.

I also taped off a large part of the hole into the toilet area. It was always too cold even when the "adjustable" vent was closed. This vent only closes a hole in the center of the vent opening. Leaving a quite large donut always open.

Oh, and I cleaned the filter. Amazing how dirty it had gotten in just three trips!

All this work seemed to increase the air flow to the bedroom which is where it was really needed.

Also, the insulated pillows stuck in the two fan openings made a HUGE difference in heat load in the bedroom. I think those things leak air and cool like a sieve.

All in all, I was not disappointed by the work from the factory. When you consider how many they must tape up in a day, mine looked pretty good.

I do question the design and hardware. There HAS to be a better, more efficient way to duct and install outlets in these things. The amount of labor involved would kill the housing industry.

 

[beardedone]

I have just started reading this thread and I have a few questions.
#1 - I have an 09 Landmark, so would this apply to that model?
#2 - Has anyone with an 09 tried this and seen any improvement?
#3 - The way everyone talks about taping up the system, how do they access all of it without taking the ceiling down!

 

[BobSue]

access

My 3055RL BH is an 09. I don't know how it looks in a Landmark but I suspect not much different.

You cannot access any of the ductwork without pulling ceiling.

But you can pull off each air outlet (simple 4 screws into ceiling) and tape each of those and what you can access from there (not much). Be very careful when reinstalling. You are screwing into very thin material. I would strongly suggest a manual screwdriver and no power to keep from stripping out the screws.

Pull cover off the AC and look there. Again 4 simple screws. See how it looks and how sealed up it is and use a mirror/flashlight to look down the ductwork as best you can. I could see very well that way.

 

[bsummit]

Well I finally got around to checking my AC air flow by following timk's directions. I pulled the cover off the unit and taped all the rough and sharp edges with the foil tape. I haven't done the modification with the tent yet. I checked the duct's with a mirror and sure didn't like what I seen, the ends looked OK but where each grill was at the foil had came loose and was blocking part of the air way. I ended up taking all the grills off and re-taping all of them. The foil tape that was used wasn't as thick as aluminum foil, had holes in it and wasn't stuck. Found two locations that the duct wasn't more than an inch high. End result after about 2 hrs work, the air flow is much better than before especially in the bedroom. Later on I will install timk's tent.

Bill

 

[ChopperBill]

Well I finally got around to checking my AC air flow by following timk's directions. I pulled the cover off the unit and taped all the rough and sharp edges with the foil tape. I haven't done the modification with the tent yet. I checked the duct's with a mirror and sure didn't like what I seen, the ends looked OK but where each grill was at the foil had came loose and was blocking part of the air way. I ended up taking all the grills off and re-taping all of them. The foil tape that was used wasn't as thick as aluminum foil, had holes in it and wasn't stuck. Found two locations that the duct wasn't more than an inch high. End result after about 2 hrs work, the air flow is much better than before especially in the bedroom. Later on I will install timk's tent.

Bill

Get with the "tent"! It will make a believer out of you.

 

[Uncle Rog]

3600RL / Layout

The duct work in our rig is forward / rear, not DS / ODS................
We have lots of flow in the head / bedroom area so the tent actually directs more flow to the wrong place. I am experimenting with cutting off the flow forward to get more to the rear duct.
I am using a piece of cardbord taped to the bottom of the unit for testing, easier to take on and off for adjustments.
It seems like it will do the trick....................

 

[Uncle Rog]

Done deal, I sealed off almost 1/2 of the forward duct and have pretty even air flow throughout the rig with all the vents open. With the BR / RR vents closed the rear area is a virtual windstorm! I can't believe it took this long to mes with it.............

 

[DennisZ]

Roger
Can you post some pictures of the mod you did, I put in the tent mod, but the rear flow is still a little low, I'd like the windstorm.

Dennis

 

[Uncle Rog]

Dennis, just read your post, I have already put the grille back on but the fix for me was simple. If you refer to timk's AC section all I did was use some aluminum, lucky I had an empty coors can in stk, and blocked off part of the forward duct, the left side of the drawing. I you experiment a little you can play with the flow to adjust it to your preference. The tent was great except in our rig it increased the fow to the strong side. As I said, use a piece of cardboard to seal the bottom in between adjustments. I will try it for a while and see how it works, I might have cut off too flow to the BR. This afternoon I am going to tape off part of the vent in the head as it still has too much.............good luck

//heartlandowners.org/attachment.php?attachmentid=560&d=1148163090

 

[beardedone]

A picture is worth a thousand words anytime.
Thanks,

Gerry

 

[Uncle Rog]

Tested..........

I started out with the temp set at 75, kicked on around 9am, as OS temp went up so did the IS temp. When the IS hit 80 I raised the thermostat to 79, to give it a chance. It never had a chance. Our unit works up to about 85 deg, after that you need two units. I am thinking about abandoning the duct system at this point and pulling the trigger for a energy saver unit so that we can run two units on 30a circuit.....
If any body, timk, has any ideas I am open to suggestions, please. We usually go out in cooler weather, but it would be nice to have the option..

My pictures will not open, I will try again later........

The day was not really that hot, 28% humidity pretty high for here, but still with the head taped off which kept the BR flow about the same I had hoped the LR area would be pleasant, it wasn't. We are now inside Quail Hollow making tacos, too hot in the horn...........

 

[timk]

Roger,
Rather than trying to restrict your air flow somewhere, I would try to divert the flow to where you want it. On a hot day, everything is so marginal, you dont want to reduce the flow at all.

That said, with one ac, and all my single pane windows, I had to cover most all the glass with foil bubble insulation to keep things comfortable on a really hot day. We finally installed a second ac, and even then we still leave some of the foil in the windows.

 

[ChopperBill]

We have the 3055, the little short fellow. When we first bought it thought the a/c worked pretty good, until the temp got to the mid and upper 90's and it would only get the kitchen cool when the grille was open, the bed room was pathetic. Did the TimK tent in the vent and it is not the same trailer. Close to 100 out side and it never seems to get over 78 inside, full sun at home, and is comfy all over. Cant beat that for one A/C! We stay in the mountains most of the time in the summer and hardly use A/C. AZ in the winter and no A/C needed. A good idea is to park in the shade in the summer and in the sun in the winter. Sorry for you folks that live where it is imposable to do this. Still TimK is my hero!

 

[Uncle Rog]

Hey guys, timk you are probably right about the air flow, I will experiment a little more............
Here is some vindication for the system, when I returned home yesterday it was varying from 105-108 deg, the little receiver in the horn read OS temp 98 deg! And no RV this size is going to stay cool with one unit at that temperature........
timk has posted a bunch of good ideas / fixes for any manufacturers rv, to be honest until he posted the AC section I was confused as to what the fix was, even with Jim's photos..........................

 

[imchud]

Well , I just got the Timk tent install tonight, and wow, what a difference in the air flow, I would be willing to bet I got twice the flow I had before I installed the tent... I read all the post relating the the fix, then I had my work fab one up out of 14 gauge Stainless steel, with preformed flanges and the bend for the curve... All I had to do is set it up into the A/C unit screw down the flanges and a 1/2 hour later I was done..., very cool...... Thank you very much...

 

[Bob&Patty]

Good job Tom. Now I want one for mine. LOL BTW, I posted more stuff in your ATF post. Bob

 

[Shadowchek]

I went in there and sealed everything with metal tape paying special attention to the center devider. I did a variation of the tent in the vent but I completely sealed off any air from comming down below with sheet metal. I extended the tent all the way to the outlets. Giving a nice smooth flow. I positioned the tent part 2/3rds of the way across giving more air to the living room side. I have had it be 78 deg with a 100 deg outside temp. Very low humidity though. I guess I am lucky.

Greg