My Atwood furnace worked great when I tested it before buying the coach...I haven't tried to use it since then, but now that it's getting chilly I tried to fire it up, but the blower won't come on.As I turn the thermostat up, I hear a "click" from the furnace, and I can see a green LED on the furnace circuit baord come on. So no error codes, and since it seems to be triggering the furnace to "come on", I'm assuming the thermostat is working. Correct?I'm thinking its a problem with the blower. I have a multimeter, and have read some trouble shooting guides, but I don't think I have QUITE enough information to continue troubleshooting. For instance, when it says "check that the furnace has 12 volts". How? Which wired do I test?Any other troubleshooting tips?Thanks

Propane?12VDC?Demand?Those are the three things you need to have to have heat!

Bee hive in the blower maybe. They love the smell of gas. Do you have any screens on the outside intake or vent?

Nothing gonna happen til the blower runs....

DC Voltage comes from a 'fused' circuit at DC Dist. PanelGoes to: t-stat and to an ON/OFF switch (local on frame of furnace).From ON/OFF switch it goes to circuit board...that is ahy you have a GREEN light. Board has power.From t-stat it goes to:limit switch and sail switch where it stops until fan comes on and makes u sail switchit also goes to circuit board for the 'timed delay' function (starts fan which makes up sail switch allowing voltage to go back to board....time delay then allows voltage to gas valve & sparker) Sounds like issue is with timed delay circuit on board or with 4 wire connector on board.When T-stat makes up (CLICK) DC voltage should be on: RED wire from board to fan motor BLUE wire in 4 wire connector to boardWHITE/BLUE (could be either) wire from t-stat to limit switch/to sail switch (but not on white wire from sail switch to 4 wire connector until fan runs)

donn0128 wrote:Propane?12VDC?Demand?Those are the three things you need to have to have heat!I have propane, but that doesn't matter since it won't try to light until after the blower starts.My batteries and converter are brand new, fully charged, and I'm plugged in. I don't know how to test if the furnace is getting 12v.It's cool enough that there should be demand. Especially since when I tested it, it was a mid summer morning. It's colder than that right now.

Time to Troubleshoot the furnace | Good Sam Community

wolfe10
Explorer
Oct 20, 2015
If you do pull it to clean (a good idea), PLEASE be sure to replace the gaskets. Gaskets in good shape (won't be after you take the furnace apart) are critical for keeping Carbon Monoxide out of the inside.
mchero
Explorer
Oct 20, 2015
Not a bad idea to pull the furnace and give it a good cleaning on a work bench. Not hard to pull, just make sure you locate the screws holding it down.

I had a 93 Pace Arrow Diesel pusher with two Hydro-Flame furnaces. One was burning strange so I pulled it & found a partially rusted burner. Also found an old mouse nest in one of the ducts!
The sail switch on the Hydroflames was simply a veeder type microswitch with a long arm & small square or "sail". Hard to imagine the actual switch going out BUT mud daubers & such love to bild mini mud mansions in those furnaces. Also, the squirrel cage blowers get dirty & out of balance.
Sometimes I read threads about people who oil the blower motors because they squeak but then report back that the squeaking starts up again! The blower motors themselves run around 100 bucks.
Those Hydroflame furnaces are practically bulletproof "IF" you keep them clean and maintained. Everything, including ignitor boards in that 93 Pace was original and 100% functioning because it was maintained. Sold her last year and do indeed miss her!
zach477
Explorer
Oct 18, 2015
UPDATE: I got it working again. Before taking it apart, I gave it a few solid smacks on the top of the fan. It release the sail switch and now we're good to go. :)
zach477
Explorer
Oct 17, 2015
Ok now that it is getting chilly out and I have some time to look at it....

In order to get at the sail switch, will I need to disconnect the propane line?
zach477
Explorer
Oct 06, 2015
Well it rained for a couple of days straight, and now its 85 degrees out, so I haven't had a chance/need to dive into the furnace, but when I do I'll post the results. :)
Dick_A
Explorer
Oct 04, 2015
If the sail switch is the problem I would suggest replacing it and perhaps the igniter. They are inexpensive and easy to do at the same time while the unit is open.
enblethen
Nomad
Oct 04, 2015
The furnace is one of those maintenance items. Blowing it out at least start of each season will keep debris away from the sail switch. You can use a can of compressed air or a nozzle on your air compressor if you have one.
A vacuum will do a partial job, but the compressed air seems to work better for me.
Chris has been a great help for many people on this site.
Thanks Chris for all you do!
zach477
Explorer
Oct 04, 2015
Chris Bryant wrote:
A solid green on a Dinosaur means the sail switch is stuck closed- it's attached to the plastic blower cover, inside. The board knows it should not get power through the sail switch if the blower is not energized, so it doesn't start.

From the directions at http://dinosaurelectronics.com/Instructions/Fan50PP_inst.pdf
IF!? For some reason the fan does not come on and the GREEN LED is lit on the
circuit board, the sail switch is stuck in the closed position. The Fan 50 Plus Pins
is designed to stop and do nothing if the sail switch is stuck closed.

Nice! I'm glad we got that figured out!

Seems like something fairly easy to fix? Or will it just get stuck again next time?
Chris_Bryant
Explorer II
Oct 03, 2015
A solid green on a Dinosaur means the sail switch is stuck closed- it's attached to the plastic blower cover, inside. The board knows it should not get power through the sail switch if the blower is not energized, so it doesn't start.

From the directions at http://dinosaurelectronics.com/Instructions/Fan50PP_inst.pdf
IF!? For some reason the fan does not come on and the GREEN LED is lit on the
circuit board, the sail switch is stuck in the closed position. The Fan 50 Plus Pins
is designed to stop and do nothing if the sail switch is stuck closed.
Bird_Freak
Explorer II
Oct 03, 2015
dinosaur is aftermarket but a very good one.