jodellking Report post Posted February 4, 2015 The Atwood furnace in my Bounder 39Z is malfunctioning. On a trip from GA to MD the furnace started blowing black smoke out the exhaust. Then we had the smell of propane inside the motorhome and it set off the propane alarm. Has anyone had a similar problem and what was the issue with the furnace? Tkx Joe Bounder 39Z Toad: 2007 VW EOS Share this post Link to post Share on other sites
dickandlois Report post Posted February 4, 2015 Joe, Welcome to the FMCA Forum! First check to heater tube in the furnace is clean, with no mud dubber nests or other items. You will need to remove the ignition unit. If you move the air mixture-make sure you mark how wide the air mixture slots are before hand. With black smoke coming out the heat vent the mixture is running very rich, often caused by some thing in the fuel mixture area or in the tube itself. All the adjustments need to be set correctly for the unit to operate properly. Look in your paperwork for the owners manual for your furnace. If that black smoke smells like plastic, you need to have some other work done on the blower fan assembly Rich. Note: Make sure the Vent tube is not damaged or rusted allowing the hot air to burn the wall of the coach!! Share this post Link to post Share on other sites
wolfe10 Report post Posted February 4, 2015 Rich has you off to a good start. Quite likely the black smoke is being caused by a way over rich mixture. Something as simple as a mud dubber's nest on the burner (they love the smell of propane) can cause it. BUT, the propane getting into the coach should not be related-- the system is sealed. That is, the intake, combustion and exhaust should be totally isolated from the air path to the coach interior. So, you will want to have the combustion chamber checked. A leak here or in a gasket to it can allow fumes (and in an over-rich case propane) into the interior. You don't mention the age of the unit, but if the combustion chamber is rusted through, a new furnace may be a better option. Share this post Link to post Share on other sites
jodellking Report post Posted April 22, 2015 Hi Guys, I finally got back to this problem. A lot of nasty weather during the winter. Finally getting some 70 degree days. Anyway, I am attempting to take the furnace out of the motor home so I can see what is wrong with it. I have the gas line unconnected and all the screws on the outside removed. When I try to slide the furnace out of the motor home, it comes out about two inches and then hangs on something. I have read about a number of people that have taken theirs out but I am having problems. What else do I need to do too get the furnace out of the opening. Thanks in advance. Share this post Link to post Share on other sites
dickandlois Report post Posted April 23, 2015 jodellking, You have the wiring to disconnect and some mounting hardware holding the entire unit in place. Do you have the owners manual and / or the installation manual for your unit? Rich. Share this post Link to post Share on other sites
jodellking Report post Posted April 23, 2015 Hi Rich, I know about the wiring. It is not keeping it from coming out of the hole. I cannot get to anything up inside of the hole and something inside is keeping it from coming out. I have an owners manual but it has nothing on getting the furnace out of the hole. I have a lot of troubleshooting info on the furnace, but nothing on how it is installed. Tks Joe Share this post Link to post Share on other sites
hermanmullins Report post Posted April 23, 2015 Joe, Is the unit connected to any ducts? Sorry I can't be of much help. By any chance can you send some pictures? Herman Share this post Link to post Share on other sites
dickandlois Report post Posted April 23, 2015 Joe, Could you post the model of your Atwood furnace? What year is you 39Z and do you have 2 furnaces? Rich. Share this post Link to post Share on other sites
gbrinck Report post Posted April 25, 2015 You will have multiple hot air ducts connected to the back side of the furnace. These have to be disconnected to remove it. May also have some brackets on that side. You need to be looking form inside the coach as well as outside. Share this post Link to post Share on other sites
studebakers Report post Posted January 4, 2016 Atwood furnace model 8531 will not start. Power to circuit board-- motor will not start. Share this post Link to post Share on other sites
dickandlois Report post Posted January 4, 2016 studebakers! Welcome to the FMCA forum! The link below is for the manual covering your unit. Take a look at the information - there is a electrical drawing in the manual covering the power supply wiring and the fact that some installations include a circuit breaker. Let the group know what you find or for more help. http://www.atwoodmobile.com/manuals/furnaces/MPD%2033179%20SP%201.08.pdf Rich. Share this post Link to post Share on other sites
