Suburban furnace operating

[Blue~Go]

1999 came with a 4-button control, which did control the furnace. I no longer have the AC or furnace installed (they are in storage), but I can tell you something about the wiring to the furnace.

1) DC power wire comes from the brown box fuse panel, as you'd expect. In my rig this was position #6, a 12-gauge red wire with a 20-amp fuse.

2) The "phone cable" runs across the overcab compartment and then when it gets to the area where the solar controller is, it goes up into the roof cavity. There is a "tunnel" they built into the roof sandwich here, and it carries the phone cable and the 12-gauge solar panel wires (which end up going out through a hole in the roof). The phone cable comes into the AC hole (which is a standard 14" x 14" roof hole) on the passenger side near the front of the square hole.

3) But now hmmm, in my memory (and in looking at all the photos I took when I removed the furnace), there is no phone cable to the furnace. I could look into it more, but I'm guessing that only regular wire goes to the furnace, not the phone cable.

4) I also know that one *can* just buy a regular furnace thermostat and use that on the furnace (people who have removed the AC but kept the furnace have done this). Not saying you need or want to do this though.

[Chinnin-about]

Mine has the 5 button control panel and im assuming its original?

I don't know. Maybe others who have a 2000 model like yours could answer this. If it was an original 4 button, and you now have the 5 button, the problem could be in the compatibility between the thermostat and the control panel.

Otherwise, try the "system" reset first and see if that does the trick. (paragraph 16) http://beamalarm.com/Documents/duo_ther ... oting.html

[Chinnin-about]

If you find out that your 5 button thermostat is faulty, I still have the brand new one I bought. You are welcome to it.

[sm350bl]

Mine has the 5 button control panel and im assuming its original?

I don't know. Maybe others who have a 2000 model like yours could answer this. If it was an original 4 button, and you now have the 5 button, the problem could be in the compatibility between the thermostat and the control panel.

Otherwise, try the "system" reset first and see if that does the trick. (paragraph 16) http://beamalarm.com/Documents/duo_ther ... oting.html

Something to note here while im thinking about it. The coach is a June 2001 coach, and not a 2000. ( the van chassis is a 2000)

[sm350bl]

1999 came with a 4-button control, which did control the furnace. I no longer have the AC or furnace installed (they are in storage), but I can tell you something about the wiring to the furnace.

1) DC power wire comes from the brown box fuse panel, as you'd expect. In my rig this was position #6, a 12-gauge red wire with a 20-amp fuse.

2) The "phone cable" runs across the overcab compartment and then when it gets to the area where the solar controller is, it goes up into the roof cavity. There is a "tunnel" they built into the roof sandwich here, and it carries the phone cable and the 12-gauge solar panel wires (which end up going out through a hole in the roof). The phone cable comes into the AC hole (which is a standard 14" x 14" roof hole) on the passenger side near the front of the square hole.

3) But now hmmm, in my memory (and in looking at all the photos I took when I removed the furnace), there is no phone cable to the furnace. I could look into it more, but I'm guessing that only regular wire goes to the furnace, not the phone cable.

4) I also know that one *can* just buy a regular furnace thermostat and use that on the furnace (people who have removed the AC but kept the furnace have done this). Not saying you need or want to do this though.

Thank you, great info! I almost went nuts looking for a stand alone thermostat for the furnace earlier on cause I have seen those in other videos until I posed the question here and learned about the comfort control.

[sm350bl]

Mine has the 5 button control panel and im assuming its original?

I don't know. Maybe others who have a 2000 model like yours could answer this. If it was an original 4 button, and you now have the 5 button, the problem could be in the compatibility between the thermostat and the control panel.

Otherwise, try the "system" reset first and see if that does the trick. (paragraph 16) http://beamalarm.com/Documents/duo_ther ... oting.html

Thank you for the Doc!I believe I have this in my binder too. I did do the reset procedure as it is described here yesterday. Figure 8 is a point of interest for me right now. I need to locate that fuse panel and check position 5 for the furnace. Is that panel up in the roof unit under the cover? It was hard to tell from skimming through the info.

[Chinnin-about]

I need to locate that fuse panel and check position 5 for the furnace. Is that panel up in the roof unit under the cover?

Yes, those "dip switches" are on the air conditioning control panel on the roof. Pretty easy to access once you pull the cover off, and then the smaller control panel cover. While you're in there, check the fuse on the control panel.

[Blue~Go]

The fuse I was referring to would be the main DC fuse for the wire that runs to the furnace. It will be in the "brown box" power center which is usually on the "ell" of the sink counter down near the floor on a Concourse; probably still on the base of the sink counter somewhere on a Premier (speaking of post 1997). Turn a thumbscrew type dealie and the top half of the brown box will hinge down. The breakers on the left are AC breakers. The fuses on the right are your DC system.

On mine fuse #6 (Note: NOT number five like I said previously; number 5 is the refrigerator which is an 8 gauge red, sorry - that'll be noticeably fatter wire) is a 20 amp fuse and there is a 12 gauge red wire associated with it. That is furnace power. They might have changed it but that's the type of thing that is more likely to stay the same over the years. At any rate it is likely to be a 20 amp fuse #12 red wire, even if not the 6th one.

Here is a drawing from the 2000 Manual. Arrow on second one shows fuse I mean. Clicking once or twice will make it larger.

[BobW9]

Just a thought, but when I had to get a new roof A/C, they also had to install a new thermostat controller because of new wiring on the current model Dometic A/C units. When they did, they initially wired it wrong and left off the furnace (the thermostat did not give Furnace as an option). If I hadn't tested that before leaving their facility, it could have been a while before I realized I no longer had a working furnace. If the previous owners didn't use the furnace after some A/C work, that might be the problem.

Bob

Thats great input Bob thank you! I wonder where this wiring junctions at? I had pulled the cover off the comfort control and it has a phone style plug on the circuit board and the harness goes back into the cabinet. I could trace them out. I really have no idea of they had work done to the a/c or not. It appears to be the correct dual-therm penguin unit that corresponds the all the original paperwork in the rvs folder I got with it. If its a matter of a wire being unhooked,Im wondering if the control panel can auto-detect? After they fixed your wiring did the control panel offer the furnace option?

It was 5 years ago, but I think they just hooked up the wire that they'd forgotten about and then the thermostat recognized the furnace. I just checked and the comfort control user manual does state that you'll only see the modes that are hooked up to the device - so if you're not seeing the furnace as an option on the comfort control thermostat, then I'd guess either it isn't wired correctly, or the furnace has an electrical issue (I imagine the comfort control is relying on some signal from the furnace to know the furnace is hooked up, unless it can just tell from resistance that the furnace connection is there).

I'm not certain, but I think they needed to reopen the interior shroud for the A/C to get to where the furnace wire came through, and connect it inside there to the harness for the comfort control. Kind of like the A/C unit was the crossroads for everything related to the comfort control.

Mostly I remember waiting in the Camping World outside Austin all day from open until after 6pm because of multiple mistakes the service guys made. It was only after 5pm when they gave it back to me for the second or third time and I found the furnace not working that they finally allowed me back into their service area with the tech guy.

Good luck.

[Blue~Go]

I'm not certain, but I think they needed to reopen the interior shroud for the A/C to get to where the furnace wire came through, and connect it inside there to the harness for the comfort control. Kind of like the A/C unit was the crossroads for everything related to the comfort control.

That makes sense to me because the "phone wire" from the comfort control goes up into the AC box (under the inside shroud of the AC) but I don't remember it going anywhere else (in other words, I don't remember it going to the furnace). So there needing to be some furnace wire to that AC area (and thence to the comfort control via the phone cord) kinda makes sense.

Now that I think about it, I believe there were some small DC wires along with the phone wire. Okay, just looked at my pics from when I removed the Air-con. So, let's say you are facing the rear door and looking up at the Air-con inside shroud (and it's removed).

First of all, on the right (couch) side are some red and white DC wires. These having nothing to do with the Air-con, but instead feed the overhead lights and the Fantastic vent. They just run through the hole for convenience.

Then on the left side, there is a metal junction box with a three-conductor solid Romex type wire junction. This can also be ignored, because that is the AC power feed to the Air-con, which is not your problem we don't think.

But then, also on the left (dining) side but toward the front (cab) of the hole are the wires I think you are interested in.

1) Coming through the roof cavity and into the side of the 14 x 14 Air-con opening (from over by the solar controller) there is the "phone cord" coming in and plugged in to a phone cord joiner (from Comfort control).

2) Then, there are two blue wires coming from the Air-con unit itself. Each of these wires is wire-nutted to a pair of wires that also comes in from the roof cavity hole. The "pair" of wires is actually a round brown wire when it comes in from the roof cavity (on the side of the air-con hole), but then you can see that the brown is just a wire cover, and INSIDE that are a tiny red and tiny white wire. The two blue wires from the air-con are wired nutted one to each of those wires (one blue to red, the other blue to white).

3) There are a few other "pretty colored" wires in that area, but I *think* the only ones that come in from the roof cavity (and could thence go to the furnace) are the phone cord one, and the round brown (that's just the insulation) one that contains the skinny white and red inner wires that are wire nutted to the two blue wires from the Air-con.

I could look further if this doesn't help.