| Author | Message | ||
| Ray Drummond (Ray_d)
Registered Member Username: Ray_d Post Number: 26 Registered: 4-2006 Posted From: 68.125.99.247 Rating: N/A |
Anyone have any ideas for getting the exhaust pipe through the generator box without using the flexible connector pipe? You could save a lot of heat in the box if you did not have to use the flexible connector. I was thinking of a plate on the exhaust pipe that was sandwiched between two other plates on the generator box. Thanks, Ray D | ||
| Gus Causbie (Gusc)
Registered Member Username: Gusc Post Number: 434 Registered: 11-2005 Posted From: 63.97.117.31 Rating: N/A |
You can wrap the pipe with EHP wet blanket and stop most of the heat. Their ad is in Bus Conversion magazine. I used it on both my gen and wouldn't go without it. | ||
| R.C.Bishop (Chuckllb)
Registered Member Username: Chuckllb Post Number: 194 Registered: 7-2006 Posted From: 4.240.213.213 Rating: N/A |
Not sure I absolutely agree with you about the heat bit, but I used welded pipe and kept the radius as short as possible until it exited the vehicle. Takes a bit of doing, but not difficult. Also makes it quiet...I don't necessarily agree about the quiet, but have had "compliments" on how quiet my 6.5KW Onan is. FWIW Then....wrap it....  RCB | ||
| Ray Drummond (Ray_d)
Registered Member Username: Ray_d Post Number: 27 Registered: 4-2006 Posted From: 68.125.99.247 Rating: N/A |
Can you wrap the flexible pipe with the wrap. I did not think it would hold up, if it did, I would go that way. The flex pipe that came with the generator is about 16" long and that is why I was worried about the heat. Ray D | ||
| Chuck Newman (Chuck_newman)
Registered Member Username: Chuck_newman Post Number: 219 Registered: 1-2005 Posted From: 67.126.207.52 Rating: N/A |
Gusc, How close to the generator do you start the EHP wet blanket, and how far do you run it? I plan to have a horizontal run of exhaust pipe about 11 feet under the bus, then up through a closet to the roof. Do you think one layer of EHP will give me just a warm pipe to the touch in the closet? Can you wrap the EHP in layers if necessary? Dick Wright told me the length of exhaust is not a problem, but the heat from the exhaust pipe might be. What do you think? | ||
| Chuck Newman (Chuck_newman)
Registered Member Username: Chuck_newman Post Number: 220 Registered: 1-2005 Posted From: 67.126.207.52 Rating: N/A |
Related question to all: Am I complicating my life excessively with running the exhaust through the roof, sealing the roof, minimizing heat in closet or wall, and planning for rain to drain through the pipe? Would it be cheaper and easier to run the exhaust under the bus and out the back for most situations when generator is used, and simply investing in the Camping World vertical stack for those rare occasions when I'm camped in close quarters? All opinions and experiences appreciated. | ||
| Jim Wilke (Pd41044039)
Registered Member Username: Pd41044039 Post Number: 164 Registered: 2-2001 Posted From: 68.187.183.190 Rating: N/A |
My present bus has the exhaust exiting under the side of the bus & we use a vertical stack when we are at rallies, etc. But the bus we are converting now will have the exhaust run up through the roof with a double pipe, the outer sealed at the top. | ||
| David Dulmage (Daved)
Registered Member Username: Daved Post Number: 173 Registered: 12-2003 Posted From: 142.46.199.30 Rating: N/A |
My concern about your proposal is that you would need to carefully design it so that there was no risk of an exhaust leak into the interior of the bus; the effect of a leak could be fatal. The removable vertical stack seems to be a much simpler solution. FWIW DaveD | ||
| Greg Roberts (Eagle 20) (Gregeagle20)
Registered Member Username: Gregeagle20 Post Number: 219 Registered: 4-2002 Posted From: 66.68.239.237 Rating: N/A |
For my 15Kw unit I exited the genset with a flex pipe to the muffler and then exited down through the floor if the bay and then hard pipe goes along the bottom and then turns up into a sealed double wall stove exhaust pipe. The genset exhaust pipe is wrapped with overlapping exhaust wrap and then completely covered with the metallic tape. This whole assembly passes behind the refrigerator and exits the roof with a rain cap on top. Works like a charm and is very quiet and non-stinky. | ||
| Gus Causbie (Gusc)
Registered Member Username: Gusc Post Number: 440 Registered: 11-2005 Posted From: 63.97.117.49 Rating: N/A |
Chuck, Wrap the exh pipe as close to the gen as possible I've never used double wrap but see no reason it won't work fine. You can call EHP and talk to Penn Larson-email is pennsue@earthlink.net-. The wrap makes the heat go further along the pipe. It comes as a blanket but I cut it into strips at Penn's suggestion, much easier to apply. I see no reason not to put it on flex pipe. I did on my first gen which had two flex sections and had no problems. I would recommend applying it in short sections on flex so it will handle vibration better. Section length depends on the bend radius. The gaps will be small enough that no significant heat will escape. All that said, I don't recommend running the exhaust under the bus. If it is as low as my 4104 it will probably get damaged in some of the more rustic RV parks. My old Onan originally had a pipe underneath but it had been removed because it was damaged. I agree with DaveD, I'm no fan of gen exhaust through the roof for a bunch of reasons. In your case it appears you are almost exceeding the max exhaust pipe length before you even start to go vertical. Each gen has a max exh pipe length, look in the manual. My exhaust goes straight out the side of the bus through the original expanded metal door, the shortest I could make it. I made it just long enough to attach a vertical outside pipe for stationary use but have never needed it. My Honda came with a spark arrestor so short is no problem. The Honda is so small that I was able to put the exhaust underneath the gen box and still run it out above the compartment floor, a very neat installation. The whole thing sits on a cradle and comes out in one piece, exhaust and all. | ||
| George M. Todd (George_mc6)
Registered Member Username: George_mc6 Post Number: 251 Registered: 8-2006 Posted From: 207.231.81.129 Rating: N/A |
Ray, Be VERY careful about engine exhaust! People absorb carbon monoxide in preference to oxygen by a factor of something like 20 to one. This means that in an atmosphere of 79% carbon dioxide, nitrogen, etc, 20% oxygen, and 1% carbon monoxide, you will die of carbon monoxide poisoning. This is what can happen with a generator exhaust out the side or back of a bus, and a window open. This topic is in the archives, along with the warnings by all of us HVAC contractors! Please take the time and effort to insulate your pipe well, and run it out the top to start with! | ||
| Debbie and Joe Cannarozzi (Joe_camper)
Registered Member Username: Joe_camper Post Number: 25 Registered: 10-2006 Posted From: 76.223.83.13 Rating: N/A |
Our gen exhaust goes through the cabinates and out the roof but it is in a enclosed chase aprox. 4in by 4in. and where it goes through the floor and ceiling it is double walled. I have learned that the SPIRAL type flex pipe is only designed to be bent to shape 1 time and if used on a gen. on a slide that repeated in and out will cause it to leak. We have found a 1 piece CORRIGATED stainless piece that has been tested to 1000 times and it also makes a much tighter bend. Geib industries in Franklin Park, Ill. Hope I haven't broken any rules by posting them, it is a safty issue. | ||
| Jack Conrad (Jackconrad)
Registered Member Username: Jackconrad Post Number: 606 Registered: 12-2000 Posted From: 76.1.180.218 Rating: N/A |
Regardless how you route your generator exhaust, make sure you have a WORKING carbon monoxide detector inside your bus. When I was still working (Paramedic-Firefighter) I ran on 2 incidents of carbon monoxide poisoning in RVs. In 1 case, the occupants were not even running their generator, but their neighbor was and the wind blew the fumes into their RV. Both survived, but 1 suffered permanent brain damage. Jack | ||
| john w. roan (Chessie4905)
Registered Member Username: Chessie4905 Post Number: 718 Registered: 10-2003 Posted From: 71.58.117.21 Rating: N/A |
You can buy a woven fiberglass wrap heat tape from SUMMIT or JEGS. I think it is made by Thermo-Tec It is used a lot to wrap exhaust headers, exhaust pipes etc. Used it myself on some exhaust piping on vehicles. It stays flexible after installed and comes in 1 inch or 2 inch wide by about 25 feet. You wet it in water and wrap the pipe,s with slight overlap, which makes it set snug, but is still flexible. I won't offer an opinion on how you want to use it though. Great stuff BTW | ||
| James Stacy (Jimstacy)
Registered Member Username: Jimstacy Post Number: 94 Registered: 1-2001 Posted From: 75.41.27.80 Rating: N/A |
Our gen exhaust runs up through a closet, through the roof, and terminates with a small rain flap. The vertical pipe is run inside a "class B" double wall pipe used for woodburner chimneys. This gives three concentric pipes with two air spaces separating them. The air spaces are vented top and bottom. You can put your face against the outer pipe in the closet when genset is running. I used heat wrap from J C Whitney in the gen compartment. Worked great. Jim Stacy | ||
| Debbie and Joe Cannarozzi (Joe_camper)
Registered Member Username: Joe_camper Post Number: 28 Registered: 10-2006 Posted From: 76.223.83.13 Rating: N/A |
Here is some pics. of our recent gen bay rebuild. I used the header wrap from Jegs and have decided to get another roll and double it up.   This is before I reinstalled the dividing wall and rad. and blower. These pics. are pittifully small. What is the max. pixals by pixals? This is the biggest the site would accept on my preset choices and I know I've seen bigger. What am I doing wrong?  Here is what it used to look like. I really need some help posting pics! | ||
| Debbie and Joe Cannarozzi (Joe_camper)
Registered Member Username: Joe_camper Post Number: 30 Registered: 10-2006 Posted From: 76.223.83.13 Rating: N/A |
Here is a picture of both the safer and much more flexible new CORRIGATED flex pipe and the old SPIRAL type that we found to leak with repeated exersize on a gen. on a slide.  60 inches with ends to my spec. welded on 65 bucks. |