Basement heat

[Teroy]

Originally Posted by Grumpy

If you look at the various bottom details at the top it shows 2" and 4" drop outs which, as I mentioned, would indicate that holes or ducts are placed into the belly. I know our Pinnacle had them as one was visible directly under a floor register.

Thanks for the info. Definitely not knowledgeable on how to read the drawings. I know for sure there are no cutouts in the ducting in the front pass thru. I'll check under the cabin registers. Maybe, I'll have to track down a camera to feed into the ducting.

[Teroy]

Originally Posted by mlitt55

2019 rlts, 30' eagle ht.
My unit is very similar. If you remove the two flex ducts, and look into the base of the furnace, you'll see the floor cut out below the heater. Roughly 4"x4" going downward, cutout lined with the silver tape.
I don't have much airflow going to the rear, but lots to the bedroom, so I had to do my own investigation. Jayco and the floor plans do not show much. The drwgs will not show a cutout. Hard to detail.
You can get the build drawings from Jayco after the warranty period, with your VIN number.

Thank you. There is a hole under the furnace and it feeds into the ducting. It lines up with a hole in the bottom of the furnace. My furnace doesn't sit flat on the raised base under it. There's about a 1/2" gab between them. As a result, some of the heat is just directed into the area around the furnace and not into the ducting. I haven't figured out how to seal that gap yet. I'll probably have to completely remove the furnace.

There's also a wire that connects to the mounting bracket on the bottom right hand corner of the furnace. It is routed into the hole under the furnace but disappears behind the silver tape. I assume it's a ground between the ducting and the furnace but won't be able to tell till I remove the furnace.

[Teroy]

Originally Posted by Grumpy View Post
If you look at the various bottom details at the top it shows 2" and 4" drop outs which, as I mentioned, would indicate that holes or ducts are placed into the belly. I know our Pinnacle had them as one was visible directly under a floor register

Thank you. No holes under the floor registers.

[Teroy]

The original from Jayco:

"Thanks for contacting Jayco customer service ducting is ran to the underbelly that allows air from the furnace to run down to that underbelly to allow that to heat. I have attached a print showing how that ducting is ran./QUOTE]

I asked for clarification:
Are you saying the heat is transferred from the duct to the basement because the duct gets warm and that heat is conducted to the basement; there's no actual outlets?

Jayco response:
Correct there is ducting that runs down that transfers heat to the basement.

[Teroy]

Originally Posted by mlitt55

2019 rlts, 30' eagle ht.
My unit is very similar. If you remove the two flex ducts, and look into the base of the furnace, you'll see the floor cut out below the heater. Roughly 4"x4" going downward, cutout lined with the silver tape.
I don't have much airflow going to the rear, but lots to the bedroom, so I had to do my own investigation.

After further consideration, I realize the two flexible hoses coming off my furnace are routed to the ducting that feeds the bathroom & bedroom on the upper floor of my 5th wheel. Therefore, the cutout in the floor under the furnace is how the heat is routed to the cabin ducting. My furnace does not sit flat on the floor and as a result there is a gap (probably 1/2") between the furnace and the opening in the floor. This allows some of the heat to just be discharged into and around the compartment where the furnace is located. mlitt55 Does your furnace sit flat on the opening?

[440 scout]

This may be helpful. While adding more insulation around the fresh water tank of a Grand Design 5th wheel, I saw a 2" diameter open heat supply duct that just deadended there. Traced it back towards the furnace and found it connected to a Tee that was spliced into one of the 4" supply ducts. So, even though it was a different brand camper, its possible Jayco may use that same system to heat the underbelly. And there may be more than one of those 2" heat supply ducts.

[Teroy]

Originally Posted by 440 scout

This may be helpful. While adding more insulation around the fresh water tank of a Grand Design 5th wheel, I saw a 2" diameter open heat supply duct that just deadended there. Traced it back towards the furnace and found it connected to a Tee that was spliced into one of the 4" supply ducts. So, even though it was a different brand camper, its possible Jayco may use that same system to heat the underbelly. And there may be more than one of those 2" heat supply ducts.

Thanks for the suggestion. I checked; there is no 2" hose and no tee into the 4" flexible pipes. Jayco confirmed that the heat to the basement is provided by convection from the underfloor ducting to the basement area (as was suggested by TxLoser). I'm only waiting for Jayco to confirm that my heater should sit flush on the 4" hole under the furnace. Right now there is the 1/2"gap there.

Thank you everyone who responded. This forum is fantastic.

[Teroy]

I received a response from Jayco about the gap between the heater and the hole cut into the floor above the cabin heat duct. According to Jayco:

"From the photos and speaking with someone else in our office this appears to be normal and per design of the unit."

I'm still not convinced this is the efficient way to go. If anyone else has a similar setup, I'd appreciate hearing if your furnace sits flush on the opening.

[Teroy]

Some of you may have read my posts about the sail switch. According to Dometic the switches are specific to the furnace serial number. In order to get the s/n I had to pull the furnace out.

By doing that I could also see the opening under the furnace leading to the cabin ducting. It's much larger than I imagined. I had inquired from Jayco about the gap under my furnace and should it sit flat on the opening. Their response was that it was designed that way. Obviously that is correct. However, as you can see by these pictures, there is a foam gasket between the furnace and the opening that seals the connection. The first picture shows you a piece of gasket attached to the leading edge of the furnace. However, (as difficult as it is to see) the gasket on my furnace is flattened on three side and does nothing to seal the connection.

Pulling the furnace also allowed me to vacuum out all the dirt and debris.