Install Complete

[Russell E Johnson]

I got the new Suburban 40,000 BTU Furnace and the new Atwood 6 gal water heater installed.  A 2 day project, but well worth the effort.  Have to get a new gauge for the propane tank and get it installed.  After that I get the propane tank filled and we will be ready to start our expedition the 28th January.  We will be heading to Arizona first then on to Oregon, Montana, Iowa, Illinois, then home again.

[Russell E Johnson]

Will know for sure when I get propane and unwinterize the MH for the test. But am hoping for the best.

[Jim Stoltz]

Awesome! Good luck!

[Russell E Johnson]

Thank you.

[david craft]

Russell...was that a 40 you took out? As a rule...1000 btu per lineal foot. You need 4 unrestricted 4" ducts for that size. Otherwise the high temp limit might cycle. Merry Christmas BTW...

[Russell E Johnson]

The one I took out was a 30,000 but our Southwind is 35 feet and has 4 4 inch outlets.  We use our MH year round so it will be in cold weather that it will get used.  Where we are headed to in AZ is the high desert in the north where temps can get down into the 20s and at times into the teens.  It may be pushing the limits for heat, but I felt it was worth the risk with the over limit switch.

[david craft]

I knew you did some cold weather camping so i dont fault your choice one bit. One outlet is required for each 10,000btu so i just wanted you to be aware. I think you made the right move(35' with all the glass up front)...a lot of mfg would have just had the 3 on the 30. So, i spoke up...

[Jim Stoltz]

Mine has 3 on a 35,000. I want to put a 4th, however, because my heat stops about mid-ship. They put one duct in the bathroom, which gets stupid hot, one in the hall outside the bathroom and one in the galley. They didn't bother running the heat forward of the galley counter so the front lounge area gets crazy cold. I need to run a duct under the couch to get warm air up front.

Would "y-ing" one of the existing ducts be as effective as installing another outlet directly at the furnace (if that's even possible - I know there's a 4th, unused outlet but I don't know what's in the way)?

[david craft]

Jim, I'm assuming that the hall duct is on the bedroom side of the privacy door. Bedrooms can usually run a little cooler because we generally like it that way. In your case, I would run a parallel duct up front like you said. Then I could put an adjustable restrictor duct in place in the bath and throttle that sucker down. The closer the y to the furnace the better, one or two feet being preferred. Really that last knockout ought to be used.

[Lakota Wolf]

David got my attention with the BTU rates etc plus ducting.. My 24 footer 5th wheel has a 30K Furnace and 4 vents. The furnace is on the right side (drivers side), and one vent is in Bath, next vent is 10 inches from furnace, then next vent is additional 36 inches away, then last vent is up in the sleeping bunk up front, approx 9 feet.  What got my curiosity,, is,,, Is this furnace *over-kill? 

Each vent has a twist turn off, and the ducting is of the same size,, all at 4 inch. BTW. This is a *factory furnace and for 30 plus yrs old, works like a champ.

[david craft]

With all the cold cimate your in, Id say your ok. With the 2 short runs your almost like having a 5 duct system. Its better to have too many ducts than too few. You could totally close the 3 footer and even restrict the bath a little as well with that short 10"er venting so well. You just want the equivalent of 3 unrestricted with the 30k. Actually with the raised bedroom, its prolly plenty warm there. Bigger furnaces heat faster and cycle more often. Smaller run longer.

[Lakota Wolf]

Thanks David.... I always assumed mine was kinda over kill.. the furnace will kick on sound like a mini rocket leaving the launch pad,, run a few minutes and roast the interior like an oven baking cookies, then cycle down with heat off and squirrel fan will run for a few more minutes..... I usually set thermostat at 68 and if real cold out I will kick on the roof heat just to take the initial chill out of the air, (roof air/heat combo unit. Electric). I asked about the overkill issue, because a friend bought a newer 2011 Model Nomad and his furnace is only 10 K for a 26 footer.

(bumper pull, flat floor pan with 4 ducts). His furnace almost always runs NON stop, sucking his propane down rather quickly. and maybe getting his temp inside up to low 60's on a 30 degree night.

[Jim Stoltz]

Thanks David. The bath has a restrictor plate that we keep closed. Even with it closed, it gets pretty warm in there unless it's REALLY cold outside. But it's much better with it wide open. My GF found out the hard way that it really heats up the toilet seat when it's wide open.

The duct in the hall is head of the bedroom privacy door, but behind a second door that - when both doors are closed - makes a big bathroom (shower on one side, toilet and sink on the other). With the bedroom furnace running as well, that hall duct is overkill. I was thinking of putting a restrictor plate on it, too, in order to force more air up front.

I'll see if I can get a collar on the unused knockout for the couch heat. Trouble is that the generator is under the couch so there's not much room for a duct. I was thinking of one of those flat, rectangular dryer ducts.