Questionable Jayco furnace installation

[Rustic Eagle]

Had to replace my Atwood furnace sail switch recently, but found an unrelated Jayco factory installation issue that was representative of "throwing something together".

My Atwood furnace doesn't have an outside access panel to the furnace so it has to be removed to access the sail switch, but I found it difficult attempting to remove outside exhaust vent assembly. Further investigation I found that the floor mounted furnace was installed at an angle (not flat on floor) which put the weight of the furnace on the outside plastic exhaust vent extension (part of the exhaust pipe assembly).

Once I had the furnace removed I was able to remove the exhaust pipe assembly. The plastic vent extension is a "slip-fit" piece that is inserted through a hole in the back panel of the furnace.

It appears Jayco didn't locate the 3 1/2" clearance hole in the outside wall per furnace setup requirements, so rather then correct the error they just let the weight of the furnace set on the plastic vent extension, and screwed down the opposite end of the furnace to hold the unit in place.

The following pic shows furnace resting 'flat' on floor per Atwood specifications, but the furnace's black back panel hole isn't centered with the sidewall cutout hole.



Long story 'shortened', lowered the outside 3 1/2" wall hole by approx. 5/16"..., which now meets Atwood's setup dimension.

Plastic vent extension properly located and inserted into furnace, thus minimizing possibility of moisture intrusion........



Exhaust tube properly positioned within vent extension and inserted into furnace tube ..., and fortunately the chrome cover hides most of the prior mounting screw holes.



Butyl putty tape will be my friend during this repair

Bob

[JFlightRisk]

That's what happens when you measure once, cut once! I'm not looking forward to any furnace work on ours. It's under the couch inside a plywood box.

[RedHorse1]

Rustic,
Will the hot exhaust be a problem with the butyl tape? I’m sure you’ve thought this thru and it won’t. Jus curious about your observations.
Some of the posted examples of “craftsmanship” on our units is alarming (tried to use a polite word).

[Rustic Eagle]

Originally Posted by RedHorse1

snip......Will the hot exhaust be a problem with the butyl tape?.......snip

I plan to use Reflectix foil tape to close up any openings (due to my cutout correction) around the plastic vent extension and outer wall, and use the Butyl around the perimeter of the exhaust pipe assembly/aluminum siding pretty much like it was.

At least the plastic vent extension is now level (not pitched), and there is a raised lip around the inside diameter that keeps moisture from compromising the inside of the furnace.

This is what my two-piece exhaust/vent assembly looks like......



Made the repair yesterday and plan to give the new switch a week to provide itself out then I will button up the exhaust assembly.

I agree, there has been a notable increase of "craftsmanship" issues with Jayco products the last few years...., lack of accountability and pride in workmanship within the production environment.

Bob

[Rustic Eagle]

Originally Posted by JFlightRisk

snip......I'm not looking forward to any furnace work on ours. It's under the couch inside a plywood box.

Same as mine, had to remove the jack knife sofa........



The exposed furnace area is placed against the outer wall..., and the plastic vent extension collar (slip fit) and metal exhaust tube are inserted through the hole at the lower right of the furnace......



Bob

[JFlightRisk]

Our TT is so small inside, if I have to remove the jack knife sofa (more like a love seat), and block myself inside until it was repaired. Not sure where I'd be able to put it.

[mokurt]

I have been wanting to take a look at mine to see if there are any install issues.mine is under the couch.
Thanks for the heads up

[norty1]

Seems like if you wanted to check the hole alignment, it would be simpler to just remove the vent and collar and look at the 2 holes to verify if they are in the correct orientation.

[Rustic Eagle]

Originally Posted by norty1

snip........it would be simpler to just remove the vent and collar.......snip

Wouldn't have to even do that..., if the furnace is installed "flat" on the floor (not angled like mine) there shouldn't be any alignment issues.

Bob

[Rustic Eagle]

Add the following to questionable furnace installation practices:

My system has two hot air plenums...., one is 14" long runs from bottom of furnace then joined to the side of the main 15ft long plenum that feeds 4 floor registers.

Where the two plenums are joined you will see a rectangular metal tube that appears to placed there to hold the plenum joint from collapsing, and/or was a means to hold the two opposing plenums together making it easier to install as one assembly. I contacted Dometic-Atwood and they tend to agree...., what isn't known is the effect on air flow around the 90 degree plenum(s) connection.

View of metal tube from furnace discharge area (tube screwed in place).........



View from floor register on main plenum......



View from floor register opposite end of main plenum.....



The two previous pics show how far the tube and furnace plenum are inserted into the side of the main 15ft long plenum. IMO this has to be disrupting the heated air flow exiting the furnace's 14" long plenum, and/or the furnace bottom discharge.



Bob

[Dopalgangr]

The exposed furnace area is placed against the outer wall..., and the plastic vent extension collar (slip fit) and metal exhaust tube are inserted through the hole at the lower right of the furnace......



Bob [/QUOTE]


Hey Bob,

Just wondering, I have a 2018 Precept 31UL and my furnace looks like yours from this picture. I assume you replaced the sail switch on the front there at the blower with the two blue wires? My docs show its an Atwood but show several models with two different sail switches. #31093 SM and #31094 SML.

Two questions:
1. Can you tell me which switch you used and if that solved your issue?

2. Mine is coming on and running for about 35 sec. then cutting off and never sparking to ignite. IF I take it all apart and fiddle with it sometimes it runs and will run and come on and off ok. Eventually (usually at 2-3am) its starts this where it will not fire. Has the three blinking lights indicating a Ignition Lockout Fault. Do you think the sail switch is the culprit? Also from the documentation it shows the sail switches having like a paddle on the end of the arm, however mine is just a short rectangle.

Thanks,
Glen

[Rustic Eagle]

Glen,

For reference my Atwood furnace is Model #AFMD 20121 installed in my 2018 Jayco JayFlight.

The Atwood documentation that came with my furnace called for a #31093 sail switch, which I ordered/received but wasn't a match. I called Atwood and determined that the correct sail switch is now packaged as a kit (switch, plastic mount, screws) is #33082. I believe the switch in the 'kit' is #33063 but is no longer sold separately.

I reordered/installed the #33082 sail switch a number of weeks ago and haven't had any issues with my furnace. My switch has two blue wires on one contact and one blue wire on the other. My furnace experienced the same symptoms as yours.

Here is what the #33082 kit looks like:



The paddle is flat, no bends. I was told that some model furnaces (prior to 2017) don't use the plastic mount.

Bob

[Dopalgangr]

Thanks Bob,

I'm going to order what you did. Is that something you were able to get off of Amazon or where did you order yours from? Thanks again

****$35 from RVEparts.com

[Rustic Eagle]

Glen,

I ordered mine through the same supplier, "rveparts.com". They did run out shortly after I received mine 3 weeks ago, but I was told they had 100 more on order, this was 7-10 days ago.

The #33082 Kit was recently released from manufacturing and hasn't reach many suppliers yet, plus Atwood's 'new' inventory control system went down and they were unable to confirm the location of parts with their warehouses.

Many suppliers are still waiting for the #33082 Kit.

Bob

[Dopalgangr]

Bob and others, I found this great video on troubleshooting the furnace as well. Hope that it helps other out.

https://www.youtube.com/watch?v=0t8vRuGdZLw