Cougar X Lite 26 RLS / Heater Issues

[BingoBoy.1957]

Hi everyone, please bear with me I'm new to this posting stuff! Has any one else had issues with the heater's in these units? Two (2) trips to the dealer & unit still doesn't operate what I feel is correctly. The unit now does make set-point and holds it, however the blower motor never shuts down. With that said I will say that the burner does cycle, at first it's (the burner) on for approx 4 min then off for 2-3 min then back on as the night went on this cycle time did get shorter, it did this for 9+ hours. Now if I'm dry camping this is going to EAT the batteries, not to mention the ware it's doing to the furnace it's self ! PLEASE if anyone has had any experience with something of this nature please advise !!!

Thanks to all !
Jim

[chuckster57]

Welcome to the forum!!

Couple of questions. What is the outside temp and what is the set temp on the thermostat? RV furnaces do run the fan for a time after set point is reached to cool the manifold. I don't recall what that length of time is, but is it possible that you have a vent blowing on or near the thermostat, and during the cool down cycle the thermostat is reading a temp drop and commanding heat again?

[BingoBoy.1957]

Thank you for the quick reply, the OS Temp was no less than 30 deg, on both occasions, the temp SP was 68 deg on both occasions. On the 1st occasion the unit never even reached SP & lost temp through-out the night, waking in the morning to a temp of 54 deg in the coach! I did take unit to the shop after that trip & they said they found 2+ extra feet of duct line snaked around in the underbelly. After removal (spending night in it last night) at least it does reach SP & holds it, but requires the unit running constantly. There is not a vent near the T-Stat. The T-Stat is located (I feel in a strange place) near the ceiling in a corner next to the slide out on the rear wall. My vents are on the floor as most of the 5th wheels are and they very in CFM displacement, from 1.7 to the highest being 8.6. This I checked with a anemometer. The X-Lites have had the T-Stats lactated in the same location from 2015 & the 2017 has it as will.
Jim

[JRTJH]

OK, here's a "very basic" explanation of the sequence of operation for your furnace after that, I'll post a couple of "SWAG" ideas for you to consider.

This is generic description of RV furnace operation and applies to most DSI type furnaces.
1. The Thermostat calls for heat, sending DC current to the furnace.
2. A Time Delay Relay is energized and passes battery DC power to the blower motor.
3. The blower motor and fans spin, pulling air from the Air Return and generating a stream of air through the Heat Exchanger and out the Ducts. At the same time another fan pulls air from the Combustion Air Intake into the Combustion Chamber and out the Exhaust.
4. The fan air stream causes the Sail switch to close as the blower gets near full speed.
5. Power flows to the High Limit Switch and onward to the Control Circuit Board.
6. The Control Circuit Board opens the gas valve and generates a spark at the DSI Igniter.
7. The Burner ignites, building heat in the Combustion Chamber.
8. Heat passes through the Heat Exchanger, warming the air circulating through the Ducts.
9. The Thermostat reaches the Set Temperature and opens.
10. Power is removed from the Control Board and the Burner shuts down.
11. The fan continues to run to cool the furnace, until the Time Delay Relay opens again.

Now for my SWAG's. First, the thermostat might be short cycling (as chuckster said) causing the furnace to cycle prematurely and never allowing enough "furnace burner time" to adequately heat the interior air. Maybe you can take a piece of insulation foam, build a box to tape over the thermostat to insulate it from any hot air that might be causing it to short cycle. If the trailer warms up, it's the thermostat location. ?????

Second, The "high limit switch" located on the burner box may be defective. If it opens, the furnace will shut down gas flow and the fan will continue to operate to purge the heat from the burner box. Once the "high limit switch" closes again, the furnace will resume operation. This "short cycling" may only allow your furnace burner to operate for a minute or two, then cool down (repeatedly) which would never allow warm air to be blown from the ducts for enough time to warm the trailer.

Third, It may be a plugged air vent (outside your trailer) that is causing the "high limit switch" to close. You need "clear cool air" flowing into the vent to get enough "hot air out" to prevent the "high limit switch" from opening. It may be that the furnace is not installed properly on the vent assembly. ???

Fourth, Air flow through the heat exchanger has to be high enough to maintain the "sail switch" in the closed position. If the velocity of air at the sail switch falls, the gas valve will close and the furnace will go into "cool down" mode. Once the fan shuts off (about 90 seconds after gas valve closure) the thermostat will call for heat and the system begins all over again. ???

You might want to check into these few "possibilities" and see if any of them might be your problem.

Honestly, if your trailer is new, the dealership should be fixing it, but with your experiences so far, I can understand your reluctance to return for yet another "bit of guesswork" from them. I would wonder, if they haven't made progress so far, will they on the next attempt????

Anyway, consider these and keep us posted on your findings.....

Here is a link to the best "furnace service manual" I've found online. There's a detailed explanation of the sequence of operation, some great troubleshooting guides (although none for your problem) and some good, detailed schematics of the variety of Suburban RV furnace models.
http://www.bdub.net/manuals/Suburban_Service_Manual.pdf

Good Luck.

[BingoBoy.1957]

Thank you for your feed back, seeing as this is a new (2016) unit & I have never experienced this with any of my other units it's kinda taken me back. On your 4 note you mentioned the fan shutting down. Mine never shuts off, only the burner drops off, blower stays on. This I know after spending the night in it last night, for over 9 hrs... Any rate I will be returning the unit once again to the shop for once again another warranty visit. Fun part being getting the appointment, then haling it an hour one way !!!
Jim

[temccarthy1]

Do have the thermostat fan setting on " auto"? If you have it on "hi" or "lo", the fan will run all the time. On the "Auto' setting, it will cycle on before the furnace burner and then about 60 seconds later will shut off after burner goes out. I learned this the hard way too!

[MG72B]

Hello, I have the same model but a 2016. I don't have that problem but could it be the thermostat? I would start with that. Could be faulty? One more thing, ask your dealer if you can stay in his lot for the night.

[Bingo 57]

Sorry for the long laps, season has not been a good in. The t-stat was the 1st thing replaced. The t-stat has always been set to "auto". As of this post the unit is at the shop again, hoping for a better & final resolve. After reading the manual for the heater it clearly states for the stat to be mounted on an interior bulkhead no higher than 41/2 feet from the floor. From 2015 through 2017 the stat is located in the same location, leading me to believe that it must work up where it is located. Why my unit is not working properly has left a bad taste in my mouth for this units. The rest of the trailer I like very much!
:banghead:

[chuckster57]

Is the furnace a Suburban? I just dealt with a unit last week that did what you describe. Replaced the high limit switch. Did better but also found if I tapped on the 12V side of the power distribution panel, the thermostat would lose power and the flame would go out. Then tap again and things would power up and furnace would light again. Might be worth a look.

[Bingo 57]

Thanks for the reply, and yes it is a Suburban. I hesitate to dig into it my self at this time, nor should I have to seeing as that is what the warrante is for, right? I am however not oppose to dong so in 3 mo and 4 days. It has just roo-end what was supposed to be a good experience.
Regards!

[JRTJH]

Thanks for the reply, and yes it is a Suburban. I hesitate to dig into it my self at this time, nor should I have to seeing as that is what the warrante is for, right? I am however not oppose to dong so in 3 mo and 4 days. It has just roo-end what was supposed to be a good experience.
Regards!

You do have "options", even at this point. First, the furnace has a two year warranty that is managed by the manufacturer (Suburban not Keystone) after the one year RV warranty has expired. Second, Suburban has "service centers" located in most areas of the country and many of them are not "your RV dealership". You might want to review your furnace owner's manual and take a look at the warranty information to learn how to keep getting it repaired after Keystone's warranty expires and also determine which repair facility might be better enabled to repair it rather than take it back to your dealership.

Note: Even though the Keystone warranty expires in 3 months/4 days, if they haven't repaired the furnace problem, THEY should keep trying until it's repaired under the warranty obligation. The question for you is: Do I let them keep trying and if so, for how long? As I said, I'd look for a "Suburban furnace authorized repair facility" that is not "that RV dealer" .....

Again, Good Luck !!!!!

[Bingo 57]

Sir, thank you so much for your response! I was not aware of the "units" 2 year coverage, and I will research that. At this point I'm just hoping that the shop I've been taking it to will 'get-r-done'. Note they are not the selling dealership, but have been very good to deal with, and very accommodating. Unlike the selling dealership. I'll say no more regarding them. Again thanks for your time & I will keep posting as this problem unfolds.
:rolleyes::rolleyes:

[WiscTraveler]

Just my 2 cents to add to this. I have a 2017 Cougar X-Lite 29RES and experienced some of the same problem. I did not have the extended running of the blower motor but unit did take a while to get to set temperature to cycle off. Air flow did not seem to be correct from registers. Removed furnace grill and checking furnace I could feel a lot of air coming from around furnace where the ducts connect. Removed two screws and laid the cover back to find someone at the factory had not installed it correctly and it was bent and out of shape and did not seal correctly. After correcting the cover the air flow from the registers improved. I also used aluminum tape to seal off the area where the gas line comes in.

[Bingo 57]

Thank you sir! I'm hoping that upon return of the unit it will function as it should, & as I would expect it to. I'm not new to RV'ing, just to this unit. It was to be my "retirement" unit. I'm now having my dough's!
Regards

[Bingo 57]

Just tagging back in, the unit has been to the shop 2 wk's now & no word from them. When I get it back I'll do another check in.

[sourdough]

Just tagging back in, the unit has been to the shop 2 wk's now & no word from them. When I get it back I'll do another check in.


They should have given you an estimated time line...if not, the dealership failed and you should have held them to one. If it's been two weeks you need to be in contact with the service manager for an explanation and date for the completed repairs.

[Bingo 57]

Yes sir your correct, however being the middle of winter I was just kind-of thinking that maybe if I don't "rush" them it may come back fixed this time! Not like I'm going to be taking it out right away. However the first chance I do get (after I have it back ) I will be staying the night in it, just to see how it works.

[chuckster57]

I would give them a friendly call. And when they say it's done, go to the dealership and have them demonstrate that will operate as designed Before you hitch up.

[Bingo 57]

Yes sir, that is something I have learned through this hole "new trailer" ordeal is making them show me that it works. Had that struggle with a water line leak ! Thanks! I was planing on the call tomorrow...

[notanlines]

Bingo, just fooling around I found about 4 mobile repair companies within 20 miles of you.
http://www.airxcel.com/suburban/where-to-buy?address=80921&radius=25
If you still have problems give one a call.

[Bingo 57]

Thank you, I will keep that in mind. I was just hoping to get it fixed while still under the warrante period. After witch I will not hesitate to dig into it my self. I already have a hi-limit switch & I've got a mine- scope coming in to check the duct work, cause I just don't think I'm getting the flow that I should be.

:banghead:

[Bingo 57]

Will here we go.... Picked up the unit today, I must say at this point that I have no issues with the shop that has been doing the work. They have gone way out of there way to find the / a problem. In a nut shell a 30,000 BTU furnace @ an outside temp of 31 deg just isn't enough. Now the story, The tec spent 3.0 hrs with me on the unit, when we started as I said it was 31 deg outside, inside temp was at 41, brought heater on set at 54 deg took 43 min to satisfy. How ever temp in side was really 48 deg, reset t-stat to aprx 58 deg another 30 min, unit shut down again, inside temp was 55 deg. Again reset t-stat to aprox 62, unit cycled back on as expected aprox 35 min more unit shuts down, inside temp 59 deg. out side temp has risen to just 33 deg. Reset t-state to 65 deg, waited just about another 30 min, inside temp has risen to about 61 deg, at this time the unit started it's "cycling" I truly feel the furnace is just not of the size needed for the trailer for any temp below 40 deg outside. All of this time that the tec spent with me & my unit and I was not charged a dime. According to "Keystone" the shop was to have charged me for the time spent, seeing as it wasn't warranty issue, however the shop said that good customer service is more important.
I guess if I want to use this unit in "cool" weather I will have to have a supplement heat source!! Shame I really (did) like this unit!! Thanks to all for your feed-back and your input.

Bingo :confused:

[sourdough]

I don't know what others think but the time frames you posted seem a little long to me. A 30k furnace in your trailer should be OK....and heat up nicely in 31 degree weather. I have a considerably larger trailer and a 35k furnace but at 31 degrees it will heat up quickly and then run you out if you don't turn it down. I don't have a suburban (Atwood I believe).

[notanlines]

What Sourdough said^^^^^. Our trailer is 38 feet long and with both doors open to the garage the 35K furnace in 30 degree weather will absolutely run you out of the trailer. When we were at Yellowstone with 8" of snow on the ground and 23 degrees we kept the to doors closed and after the furnace heated the rest (about 10 minutes) our 1500 watt electric heater did the trick the rest of the time.

[JRTJH]

I have a Cougar XLite 27RKS, a "sister fifth wheel" to the 26RLS, that's constructed the same and is about 1 foot longer. Same furnace, same insulation, same construction, slightly larger cubic footage to heat. I can assure you that in 10* F temps, the furnace will "run you out" after about 20 minutes.

I'd believe from the description of performance with different thermostat settings, that there's something wrong, either internally with the burner box or externally, with the ducting connections and/or ducting runs. There's no reason the 26RLS shouldn't be just as warm and efficient as the 27RKS.

I'd find a different service center to go through the trailer and fix what appears to be a "hidden problem" at the current service work center.

Good Luck

[Bingo 57]

Thanks all ! Having never owned a trailer before, just motor homes, & Pkup campers I have no clue how this thing should operate. I had assumed a crap load better than it does. I've got a last ditch option of haling it back up to the selling dealer (3hrs 1 way). I just hesitate seeing that it has already been looked at, and that Keystone may deny the work. ?? I then I end up with a bill.

The time frame I listed is accurate to with-in 3min. Hence the disappointment in the unit. I haven't ever owned anything, motor home, camper, preform this poorly. I intend to get out on it this weekend & do some poking around on my own. I do feel the out put from the upper floor grates is extremely low. These are the one's they pulled 2.5 ft of extra duct work out of. at least now they will kinda float TP. And the discharge air temp is between 96 - 103, depending on the grill your cking. Best to all!!

Jim

[Bingo 57]

Will I got out on the unit as said I would. Amazing thing I found, I pulled the duct out as you enter the unit low & behold it just keep coming out (the flex duct line). I ended up removing almost another 1.5 ft from this run. I did increase the discharge CFM from this duct by almost 10 CFM. I pulled the other grate & duct & had a very nominal excess duct line. Not enough to create a bunching situation. It appears that Keystone uses the "joice's" underneath the upper bunk as a duct run. Then just cut grills in the floor above. Thus meaning that the heater is trying to push heated air down this entire joice run. ??? And having 3 grills 2 above in the couch 1 in the under belly storage. I'm looking at how I can reduce the run on this area. Will follow up latter on this. Any way just wanted to do a follow up. Thanks

[SilverRig]

I have a similar issue with my 2017 28RKS. We got it home and we were hanging out and turned the heater on. It was about 36 degrees and the furnace never shutoff. There was no airflow at the bedroom/bath area and living room was minimal. Brought it in under warranty.

They did a lot of "work" to try to improve the air flow and the change was: kitchen from 787.4cfm to 1181cfm, living from 334.6 to 374, bath from 0 to 137.8. The dealer informed me that this was the third repair (same model, same issue) he has done in as many weeks.

The other night we tried again with an external temp of 23 degrees. The furnace ran for over an hour and never achieved the thermostat temp of 63 degrees.

Based on comments that folks are getting driven out of their coaches, I am concerned that there's something seriously wrong with the design. I think it's time to start pushing for real resolution or return it.

[Bingo 57]

I am truly sorry to hear that your havin the same issues with your's, but happy in that it's not just me! As I had said I have gotten an 18 foot camera for my laptop & have found nothing in the duct lines. I was able to push it from the duct grate to the furnace itself. At this point I have accepted that is a POS & I'll have to supply supplemental heat. The open plenum design for the upper duct's is a real concern to me. I see nothing but a lot of heat loss. I truly wish there was more I could correct the issue.
Jim :banghead:

[chuckster57]

You can get vent's with regulated flow. We have had to get authorization from the factory to get paid, but in all the cases it seemed to help. The ones we did were not Keystone, so it may be some consolation that other brands have the same issues.

I can't say that the people doing the designing and engineering are all that good at the heating part. On one brand we sell, the front bedroom has NO heat outlets and relies on leaving one of the pocket doors open and the vent grill rotated to the proper position. :banghead:

[Bingo 57]

I have looked at those, however I feel this is a manf defect. And am just not totally ready to throw in the towel, granted not far from it. The RV show is in Denver next week, I hope to get a hold of the Manf rep there & "share" my thoughts with him at that time!
:twocents:

[chuckster57]

I'd be curious to hear what they have to say.

[Bingo 57]

I will do a follow-up post. Just knowing there "is" someone else with the similar issue is reassuring that I'm not crazy!!

[SilverRig]

I just contacted my sales guy and he's looking into the issue for me. Will post progress as we go as well.

[Bingo 57]

SilverRig, I'll give those folks a call in the A.M. given time. And try to push them as well.

Regards
Jim
:facepalm:

[Bingo 57]

Just a follow up, I dropped my unit off at the "selling dealer" this a.m., the service manager (different guy than I dealt with in the past) sounded encouraging. I had met with the maf rep at the show & that info with him as will. I well do follow-up's as this goes.

:dizzy:

[Bingo 57]

:) Will another up-date, Working with the Keystone rep, I feel we are closer to a resolve to this issue! The manufacturer is acknowledging an issue, and are working on a fix!! My hope meter is going up.

Bingo

[sourdough]

:) Will another up-date, Working with the Keystone rep, I feel we are closer to a resolve to this issue! The manufacturer is acknowledging an issue, and are working on a fix!! My hope meter is going up.

Bingo

Here's hoping that things work out for you.

[SilverRig]

Both Bingo57 and I teamed up. We've worked with the dealer's service manager who's been great but has his hands tied. Seems that Keystone needs to authorize the warranty work on this magnitude in order for the dealer to get paid. We both have contacted the Keystone Manufacturing Rep and we've been working with him. Seems that there are a handful of units in the Rocky Mountain region reporting the same issue.

What I really need is for folks to start chiming in here, in order to establish how wide spread this issue is. Obviously, if folks aren't having heating issues in their coach they aren't looking here, but those who do I'd really to have some data to go back to Keystone with.

Thanks in advance!

[kcandred]

I'd like to chime on this issue. We are new owners of an 2017 Xlite 28RKS, purchased in late January. As it is winter and we haven't ventured south from here in Kentucky yet, we have only had it out twice. The first trip was in the 40s overnight so it didn't have to work very hard to make temp, but two weekends ago we took it out and had a high 20s overnight temp. The fan ran nearly all night. I started investigating the next morning. As my unit is a rear kitchen unit the furnace is basically dead center rear. It has a flex duct that wraps 4-5' around the back corner and comes out under the stove, it blows like mad. But my floor supply in the living room has very little air flow, the bath room forward of it is less and the bedroom up front is almost undetectable with your hand. Needless to say we had a chilly start to the morning in the bedroom. I will be watching this issue as it evolves. I am in central Kentucky, so not in your region, so please spread the word that it is likely not confined to your area. I have not had the unit to my dealer. Number one it will take months to get in, and two Id like to have more info to go in with to prevent the wasted time visits. Thanks for all your inputs.

[SilverRig]

Kcandred,
This sounds like the same issue. I would strongly suggest that you get your coach documented with the issue BEFORE the warranty expires. Don't expect your dealer to fix it first time in the shop because Keystone says that don't have a fix just yet. Once documented I can use your dealer's name to inform the manufacturer rep that I'm working with that it's not isolated to the Rocky Mountain region.

Thank you for chiming in. I need as many owners as I can find with a similar issue to get Keystone to resolve it. In our area heat is a must for spring/fall outings.

SilverRig

P.S. - Here's the results of an experiment I ran: (If you run the same one do you get similar results?)

Problem Statement


The airflow of the heating system isn't sufficient enough to heat the coach.

Experiment



The goal of this experiment is to achieve a sufficient heat level within the coach to trigger the set point of the thermostat. The thermostat was set at 65 degrees and the outside temperature was at 44 degrees when the test started.



Thermometer placement.

I purchased an indoor/outdoor thermometer as well as two low end thermometers. I placed the thermometers in the camper the afternoon prior to the day of the experiment.

One was placed at the foot of the bed, with the bulb of the thermometer hanging over the bed.
One was placed on the arm of the sleeper sofa next to the wall, with the bulb of the thermometer hanging over the arm of the sofa.
The indoor thermometer was place on the kitchen counter, left of the stove
The outdoor thermometer was placed on top of the battery box to provide unhindered access to the outside air.

Heat Profile

The following chart shows the coach temperature changes over a period of three hours at which point in time, I aborted the test. The test was run using the AC circuit as I didn't want to burn down the battery and have it fail during the attempt to reach the thermostat set point.

Register is the term used to describe the output end of the furnace within the coach. There are four registers within the 28RKS model.



At the kitchen, under the stove/oven
In the middle of the living room
In the bathroom
In the bedroom

Since the bathroom and bedroom share the same delivery channel, the chart only records the Bedroom readings. (First column is time. Yes I started at night to use the outdoor temp.)


OutsideKitchenLivingBedroomSet PointDuration22:1246.750.15248650:0022:4545.557.25 756650:3323:1144.659.36156650:5923:3644.261.563576 51:2423:5543.862.66357651:430:2243.363.56458652:10 0:4243.1646459652:301:0242.664.46459652:501:1242.2 65.56459653:00As you will notice, there was an initial jump in temperature within the first 30 minutes. After that, while temperatures were slowly rising, the coach never reached a temperature that would trigger the thermostat set point of 65 degrees. After three hours, this experiment was terminated.

It has been my experience with my other three campers, that the set point on the thermostat would be reached within 10 to 20 minutes depending on the outside temperature.

Observations

Disconnecting the hoses at the furnace reveals there is airflow out the ports of the furnace that appears to be sufficient.
The kitchen register feeds into the cool air return. However, according to the installation manual of the furnace this isn't supposed to be an issue because a heater vent must be at least 18" from the cool air return and may be less if on a wall 90 degrees from the cool air return.
Blocking off the kitchen register created some back pressure on the furnace to push more air flow out the floor registers in living and bath but not enough to substantially change the airflow.
Blocking off the kitchen register caused the furnace to develop a slight whistle

Questions


Is the furnace the properly rated for the space that needs to be heated?
Are their any kinked heater hoses within the coach that is preventing air to flow?
Are there any obstructions in the delivery system?
Are all the heater hose connections secured properly?


Other Tests


Endoscope the heater hoses to determine blockages and/or determine if connections are secure.
Run the furnace off the battery to determine if the battery will die before reaching the set point
Disconnect coach hoses and run independent hoses on the floor through the coach to see if 'cold air return' is an issue as Keystone suspects.

[chuckster57]

It's not just a Keystone problem. Just delivered a 2017 Shadow Cruiser with the furnace in the rear and bedroom up front. This one too had barely detectable flow in the bedroom. When I asked the factory if louvered vents in the main cabin were possible, I was sternly told "leave it alone" DO NOT disturb the air flow.

I am convinced this is a design flaw, but when you look at the floor plan, where to put the furnace and not lose storage space is the dilemma. I wish the "experts" who design these things had to camp in them for a week in adverse conditions. I wish you all the best, but I'm not holding my breath.

[SilverRig]

The table I entered didn't seem to take ... I'll repost if I can figure out how to get the data in.

[SilverRig]

Picture of the chart in the previous post. The first column is the time and yes, I started at 10:12pm for the outside temperature.

[Bingo 57]

OK just an up-date on my rig it's still at the shop. SilverRig's experiment is spot on. It say's it a lot clearer than I. I've not heard from Keystone this week, and I was holding off on calling them till the 1st of the week.

Kcandred, as SilverRig said get on this asap. The more that speak up on this the better chance we all have I think. This is a design issue, it does sound like Keystone is trying to find a field remedy.
Regards

OK just settled in from moving all that white s--t (snow) we got last night & this morning. While I was out I did receive a call from the service manager from the shop where my unit is, in a nutshell he does have concerns with my unit & is in "talks" with both Keystone as will as Suburban. This was a VM so no more info was given. I will be making a call Monday. Needless to say my "hope meter" is staying tough for now. I will continue the up dates.

[Bingo 57]

Will all my fears & concerns came true today ! Yes sir-re!! Keystone is now saying that that is normal operation ???? Now how in the frick can the furnace running for 9 + hrs be normal !! I guess it's as I said in the beginning these are "fair" weather units! And in reading the posts on the axle issues with these I fear the units as a hole may have some very serious problems. I now am pondering what to do with the POS. So much for retirement. I'm not a rich man I cant afford to go the lawyer rough, so I guess I deal with it till I decide what direction I'm going. Best of luck to all else who have to deal with Keystone.

[Tbos]

You might want to consider contacting Trailer Life. They have helped others when their own efforts weren't fruitful. We camped last weekend in our TT and it went down to 32 and we had no issues with our heater keeping it at 69-70 through the night. If I'm reading your posts correctly, it seems like your dealer isn't really stepping up to the plate. I can't imagine why a good tech couldn't figure out what's going on.


Sent from my iPad using Tapatalk

[Bingo 57]

My unit as will as SilverRig's have been serviced by the same dealer, I feel in all honesty that the service manager did his best. I have no reason to believe otherwise. I had not thought of Trailer Life, thank you for that suggestion. Will look into that next.

[chuckster57]

I can't imagine why a good tech couldn't figure out what's going on.
Sent from my iPad using Tapatalk
A lot of times we do have it figured out. Furnace at the rear of the unit. 3" ducting near the furnace, and 1 1/2" branch to feed the bedroom at the other end. Air is like water and will take the path of least resistance. When I request a louvered register to regulate the flow and send more to the bedroom, the "engineers" instantly send a message loud and clear:

"DO NOT MODIFY THE HEATING SYSTEM". Changing the flow characteristics of the ducting may cause the limit switch to activate, shutting off the flame, and then when the plenum cools off enough and the thermostat says we are not up to set temp, the burner fires again and the cycle starts over.

In my previous post I stated that this isn't just a Keystone issue, and I don't know what the fix is other than " re inventing the wheel", which the factory won't pay for. My best advise is to keep the pressure on Keystone by whatever means necessary. I wish you the best!

[Bingo 57]

Thanks Chuckster, with so many of these units showing up I would have though they (Keystone) would have wanted to be more responsive. If for no other reason but to save reputation.

[Bingo 57]

Hey all just an up-date. Took my unit to a independent RV repair shop that primarily works with the appliance warranties and lo and behold they are now trying to replace the furnace unit itself due to the "primary" burner not going into hi-fire. I'll do a follow as I know more.

[Lawrosa]

Hi all.. In my search for furnace issues I am experiencing I came across you thread..

I do not own a keystone but a coachmen with a suburban furnace.

Ive read this post carefully and you all should stay on track to the issue at hand.

With thats said my issue is the same as the op's and may have more theroys on whats going on.

My background is I am a plumber 35 years.

So I have a 2018 coachmen with a suburban furnace. The first thing I noticed with the furnace and the manufacturers build on this SF 30 was they only installed 3 ducts. This is a 26 ft camper.

After turning on the furnace I notices it goes off on high limit.

Suburban states 3 ducts minimum for the SF 30. Thats fine I have 3 ducts but one is right next to the furnace going through the wall to the master. The other two are 20 ft away at the buck area and rear bath.

So why did I think the cause of the high limit is cause by? Lack of air flow I think.

So calling the dealer they sent me a whole duct kit. I installed this close to the furnace under the couch. ( Just a note all the 2017 units had this 4th duct because the furnaces of that years were an SF 35. That furnace requires 4 ducts)

so when the furnace goes on and off on high limit it will take a long time to heat the coach for sure.

Thats what I think the OP is experiencing. His may be a simple limit switch replacement for 6 bucks.

On the other hand my furnace it definitely overheating. The temp out of the ducts is extremely hot. But because of this high limit switch turning the burner on and off every few minutes I dont think the coach will heat properly in cold temps.

So for now I added a 4th duct. I have room in the plenum for a 5th which I may also add.

But here is a wrench ill throw in. Im testing my furnace when its 85 f out. Is it possible the incoming air into the unit is too hot and this is normal operation? ( I know you guys are testing in cold weather) I may have to wait till cold weather hits to test my theory to see if furnace limit switch kicks off the burner.

IMO the burner should not kick off by the limit switch.

I have not figures out my next course of action, but my dealer also is 4 hours away. And I aint driving that far for anything period. I will fix myself if need be..

But the good tip I got from here is the warranty on the furnace. I have a suburban auth center a few miles from my home.

I am going to go there tomorrow and pick the guess brain there. I already have this documented through coachmen and they are the ones that sent me the additional duct at no charge.

1. Ill probably get a call into suburban tomorrow to see what they say
2. I will hit the suburban auth center tomorrow to see what they say
3 will call dealer warranty dept to see their response
4 then make a call to coachmen to get paid if there are any out of pocket expenses on my end.

There is an issue..... I just have not figured it out yet..

Pics of 2017 model with duct, and my unit missing duct. And pics of my adding one duct. Still hi limit issue. Dont know if because its not cold outside, or there is an issue of air flow or mechanical issue.

http://www.keystoneforums.com/attachments/photobucket/img_242858_0_08eab068493e66f7e4409ce62de8880c.jpg

http://www.keystoneforums.com/attachments/photobucket/img_242858_1_04720936b6d888ded1a3f37e2c96bbed.jpg

http://www.keystoneforums.com/attachments/photobucket/img_242858_2_5e41631a6bf3292806d7fa78cbbf75e9.jpg

http://www.keystoneforums.com/attachments/photobucket/img_242858_3_71f506afe3f2e1ce93b54ad02438684d.jpg

http://www.keystoneforums.com/attachments/photobucket/img_242858_4_9c2ee686ddc6fe2bfcaa7c2cf2effda2.jpg

http://www.keystoneforums.com/attachments/photobucket/img_242858_5_37f171a2e6a3db2b9ec4c60f4e4ff673.jpg

http://www.keystoneforums.com/attachments/photobucket/img_242858_6_f5f11548b98cfa522dde9896cd845838.jpg

http://www.keystoneforums.com/attachments/photobucket/img_242858_7_59274e2debda4ab7ab7905baaa031bef.jpg

http://www.keystoneforums.com/attachments/photobucket/img_242858_8_2ff31bd4aa51a0fdefbc204778c07457.jpg

http://www.keystoneforums.com/attachments/photobucket/img_242858_9_c2fa9ccc032ba9a411665580749a2b51.jpg

http://www.keystoneforums.com/attachments/photobucket/img_242858_10_1d02310aa8736ca249e7cdfc8983de6e.jpg


Below pic....two ducts where I am standing. And one in the master. None in the middle of the camper. That t stat will never get satisfied....


Ill probably add the 5th duct. IMO add all the ducts you can out of your plenum....

I will add the 5th duct nect to the other I installed under the couch.

http://www.keystoneforums.com/attachments/photobucket/img_242858_11_cd18bc802c46d2f680d76cc8221833b7.jpg

[Bingo 57]

Thanks for the in depth reply. Just this past weekend I was able to confirm that I believe my issues have been resolved, the issue hi limit switch. The night time temp's dropped to just around 41 deg, not as cool as I wish it would have gotten, but for this time of the year about average. For this I paid a private rv repair shop. No customer should have gone through, experienced the grief that myself & at least one other have. Could I recommend this couch to someone, based on the customer service alone NO. I wish you the best of luck with your struggles.
Regards
Bingo

[Lawrosa]

So your issue was the high limit switch???


So yours was defective and the furnace box was not reaching temperature.

Mine is the opposite. My furnace box gets super hot that the high limit goes off..

[Bingo 57]

Correct, mine was "breaking" before it reached temp. Then it would start the cycle of bringing the burner on & off.

Bingo

[Bingo 57]

Just a follow-up been out several times now this summer & the furnace has work flawlessly. Shame it took over a year & countless calls as will as 60+ pounds of propane.... So now I am finally getting to do the "new owner" shake down on the unit. Socks for me, anything I do and have found now is out of warranty! At anyrate I do like the unit for the most part. Happy camping to all !
Bingo

[Bingo 57]

Fallow up, coming up on end of the season here. Have had unit out several times and have no issues with the heater. Up side to the end of this I have been in direct contact with Keystone, and they have agreed to reimburse me for my out of pocket expenses!!!:) This has taken far to long to resolve in my opinion as will as far to much STRESS ! I do now have a reserve hi-limit switch !
V/R
Bingo

[BAPotter]

Read all the threads with interest.

Not sure why but Keystone used an Atwood 30K on my Bullet 251RBSWE. In the installation manual this one calls for a minimum of three 4" ducts, with the following notation: "*Note the table is for minimum requirements and should in most cases allow the unit to operate correctly. If the burner cycles on and off on the high temperature limit. Extra ducting can be used to help correct this condition due to restriction or bends in duct work."

Here's the link for the rest of the specifics. http://www.americanrvcompany.com/assets/images/atwood/Furnace-Installation-Manual-for-Medium-Furnaces.pdf

Hopefully you can locate similar info in the Suburban Install manual.

[Bingo 57]

Thanks for your feed back, however in my unit there are 4 ducks being used. 1 to the upper area, 1 to the belly area, 1 to the center of the couch, lastly 1 to the rear of the couch. I just returned from a trip where the night time temps dropped to mid 20's & my unit stayed in the 68 to 70 deg range easley. Probably could have run it warmer / hotter, just for me that was more than comfortable. Thanks again for your feed-back!
Regards.

[Johnny's Journey]

Unbelievable story. But I understand all to well. I won't go into what I had going on with mine but I do relate to all the BS that is handed off as normal and or correct.

[Bingo 57]

Just another follow-up, got in from another weekend out with nighttime temp's dropping into the mid teens and again the unit (heater) worked without issue at all. I'm learning the "sweet" spot on the T-Stat is just around 65 deg to keep the trailer at a comfortable 69 - 71 deg. Again thanks to all for your interest.
Jim

[Fastfreddie5409]

Have a 2017 Cougar 30 RLI. Love the trailer but have little or no heat coming through the 3 vents.
Live here in Canada where one needs heat on cool nights, especially spring & fall.
Will not get up to temp ever with flow just dribbling out of vents.will barely blow a kleenex off the vents.
Anyone else out there with similar issue?

[Bingo 57]

FF, I assume you have read this post from the beginning, That being said you'll see the final resolve for "my" issue was a combo of things 1) excessive duck line, by pulling the vents up / out by eliminating the extra line I increased the flow by around 30 - 40 %. 2) Ultimately my core issue was my High-limit switch causing the furnace to short cycle. After correcting both these issues I now have a unit I enjoy into early winter. Best of luck!
Jim

[oldmanbill]

I have a 30FKV with a little different situation. I use electric heat to cut down on LP costs. Down to freezing the electric will do fine keeping mid 60's near freezing. I try to set the thermostat for furnace to take over below that. Set at 65 it works fine, but set lower it will click on and off never heating, waking up to 60, 61. Makes annoying noises all night.

[oldmanbill]

I might add, I use two ceramic heaters both on low for a combined 1500 watt load. The fireplace in the living area will heat the cord on high doing nothing for the bedroom. A unit in the bedroom on low and the fireplace on low does good even heating without taxing the electrical system.

[Logan X]

I have also heard of people using “Mr Buddy” heaters instead of the on board furnace. I guess they are very quiet and safe to use inside.

www.amazon.com/gp/product/B002G51BZU

[oldmanbill]

With a tight trailer I am a little leary of non vented lp. I lived several years in a drafty Coachman and use 20,000 btu Procomm blueflame, very nice heat. Here the furnace keeps the tanks warm also, so use it.

[oldmanbill]

another great heat source for mobile units is an Espar truck heater, I have a 53 foot commercial trailer using one. Dead if winter uses about 1 gallon diesel a day, forced air nice dry heat with vented cumbustion. It keeps the whole trailer at 70 on low speed. Made for battery use.

[Logan X]

With a tight trailer I am a little leary of non vented lp. I lived several years in a drafty Coachman and use 20,000 btu Procomm blueflame, very nice heat. Here the furnace keeps the tanks warm also, so use it.

I would definitely crack a window for ventilation if I used a propane heater.

[travelin texans]

I would definitely crack a window for ventilation if I used a propane heater.

I would "open" a wIndow if using a propane or diesel fired heater!!
On second thought I WOULD NOT use either indoors regardless of their safety claims.

[oldmanbill]

diesel truck heaters are vented and totally safe.