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dannyo · 01-13-2010, 03:10 PM

So, with weather in the teens (I didn't think Austin could get so cold), I decided to see if my furnace worked. These were my steps:

1. Turn thermostat all the way down.
2. Turn on gas.
3. Open furnace panel access door.
4. Turn on switch on furnace.
5. Turn thermostat up to 66.

The results of this were nothing. Was I doing something wrong? Any direction would be much appreciated.

Thanks.

Minno · 01-13-2010, 03:27 PM

Hi Dannyo,

2 questions:

1. When you turned up the thermostat, did the furnace blower motor come on? If no, see below.

2. Do you have propane bled through the lines? A quick way to tell is by lighting a burner on the stove. If it doesn’t light right away, but you can see air blowing on the match, wait a few seconds for the air to bleed out of the line, and then the burner to light.

If the blower motor (the furnace fan) does not turn on, then here are a couple of things to check and try.

1. Make sure you have 12 volts at the furnace. You might have a blown fuse, or if you’re not on shore power, your batteries may be dead.

2. Take off the cover of the thermostat. You’ll see two wires attached to terminals. When the thermostat calls for heat, it’s supposed to close the contact between those two wires. Take a short piece of wire, or anything metal really, and temporarily jumper the two wires together. If the blower now comes on, you have a bad thermostat. If the blower still doesn’t come on, and you have 12 volts at the furnace power input, then it could be several tings wrong in the furnace itself.

Check and try these, and report back your findings. Lots of people here to give you additional advice.

Good luck!
Chris

Minno · 01-13-2010, 03:31 PM

oh - I forgot something. If the furnace blower comes on, but you don't have gas, the regulator may be frozen closed, or you may have really low levels of propane in your tanks. Propane does not work very well when the tanks are close to empty and it's cold out.

Chris

dannyo · 01-13-2010, 10:03 PM

Chris, thanks for the help. I never got any movement from the blower, so I am going to assume electrical. Tomorrow morning I'll give it a shot again.

My propane is a little low, so I should also get a refill to cover all my bases. Thanks again.

Danny

Lumatic · 01-14-2010, 06:44 AM

Could also be a mud daubber nest in the blower.

Listen carefully for a click at the furnace when you turn up the furnace. If you here a click you should have electricity to the unit.

dannyo · 01-16-2010, 10:33 PM

Chris, you say to " Make sure you have 12 volts at the furnace." How would I check that? With just a basic circuit tester right at the connection? I know, a whole lot of ignorance/inexperience on my end. Thanks again everyone.

Minno · 01-17-2010, 11:11 AM

Hi Dannyo,

Do you have a volt meter? Or even a 12 volt test light? If you don't have either one, I'd suggest investing in one or the other. Believe me, they'll pay for themselves quickly.

Yes, test for 12 volt DC at the junction where the wires come into the furnace. You'll probably need to remove a cover to get to the wires. There should a total of 4 wires - one 12 volt, one ground, and two that go to the thermostat. Not sure what color wires you'll find. The ground wire should be fairly easy to pick out as it will attach to the frame of the furnace or the metal box. If you find you don’t have 12 volts there, then you probably have a blown fuse that feeds the furnace circuit. Do other 12 volt items work ok (like the interior lights)?

If you can post pictures of the wires feeding the furnace, people here can help you figure out which wire is the 12 volt supply.

Chris

sharbours · 01-17-2010, 01:11 PM

My troubleshooting checklist would be something like:

Is there propane? If the stove comes on, you have sufficient propane to start the furnace, and the lines should be mostly purged of air.

Furnace won't start. Check the instructions for your furnace and see if you can start the furnace pilot light manually using a stick lighter. This might take a few minutes as the last of the air is purged. On my older unit, I have to hold in an override switch to allow the propane to flow at the same time I am lighting it, and continue to hold the override after it is lit for about 30 seconds until the sensor near the pilot light is warm enough to disable the automatic safety shutoff. Once the pilot light will stay on by itself, you should be able to turn up the thermostat and see the burner start behind the glass viewport, and hear the the fan kick on.

If there is no option to start the furnace manually, you'll have to start troubleshooting the electrical side.

Sean & Sharon
'75 Argosy 24'

Lumatic · 01-17-2010, 01:27 PM

Quote:

Originally Posted by Minno

There should a total of 4 wires - one 12 volt, one ground, and two that go to the thermostat. Not sure what color wires you'll find. The ground wire should be fairly easy to pick out as it will attach to the frame of the furnace or the metal box. If you find you don’t have 12 volts there, then you probably have a blown fuse that feeds the furnace circuit. Do other 12 volt items work ok (like the interior lights)?

If you can post pictures of the wires feeding the furnace, people here can help you figure out which wire is the 12 volt supply.

Chris

The thermostat wires are probably blue or gray and are have no power supply outside of the furnace. The positive, hot wire is probably red. The remaining wire should be the ground.

Gosman · 09-26-2010, 05:00 PM

Guys here is my problem with my furnace and i am a new owner of a 1975 argosy that i have just finished redoing .
First let me start out by telling you this
i can push my thermostat up and the blower will come on ,so i know the blower works.

I am not sure when the furance was run last!

I do not know how much fuel are in the tanks ? All though the stove did light .

So her is what i did

first set the thermostat to the lowest position and then opened the door and pushed in the botton and did not hear or smell fuel and i then push the other knob and heard a click and saw a spark but nothing .

So i went out turned the tanks off and 5 mins later turned them the tanks on again and went through the procedure once again except this time i opened the door and tried to light the pilot witha match and again the same issue nothing .
Question do you feel i do not have enough fuel!

Question should i clean the furance and if so could someone give me step by step procedure having never done this in the past.

As i mentioned in the beging the blower does work , were do i go from here????? Need help
thanks

sharbours · 09-26-2010, 10:36 PM

Hello Gosman, sounds like you are almost there.

First, make sure you have some propane in the tank used to feed the system. If you can light the burners on the kitchen stove, you should have enough to run the furnace, at least for a short time. Lighting the stove burners for a few seconds helps purge the air to the furnace. If you are unsure of the condition of the hot exhaust vent for the furnace, CHECK THE FURNACE VENT OUTSIDE THE TRAILER FOR WASP NESTS, and make sure if any flaming wasp nest paper floats out, it won't start anything else on fire. Leave the doors and windows open if this is your first test up of an unknown system.

Set the wall thermostat to a little lower than air temp, whatever it takes so the fan is off, but NOT all the way to the lowest temperature setting, as this may shut off the system completely. On my '75 unit, I have to hold in an override switch (the top push switch behind the panel) to allow the propane to flow at the same time I am lighting it with a butane stick lighter(loosen one screw on the viewport, rotate it down, and insert stick lighter to just above pilot light), and continue to hold the override after it is lit for about 30 seconds until the sensor near the pilot light is warm enough to disable the automatic safety shutoff. If there is air in the system, you will see it push the flame of the lighter around or even blow the lighter out. As soon as the propane purges the air, the pilot will light. This might take a few long minutes (Did I mention this might take 5 minutes or so? Very uncomfortable when laying on the floor). Once the pilot light will stay on by itself, you should be able to turn up the thermostat and see the burner start behind the glass viewport, and hear the the fan kick on. Don't forget to close the viewport and tighten the screws if you used a lighter. You should feel warm air in a few seconds coming out the vents. Let it run for a few minutes, and check for any obvious propane leaks or bad smells. If everything looks okay, close the door and windows, and check again. Bring it up to a comfortable temperature inside, and check again. If everything seems okay, congrats, you've probably got a good furnace. If you do smell a tiny bit of propane, check that the cook stove oven pilot is set to off, or if it is set to on, make sure it is lit.

Enjoy!

Sean & Sharon
'75 Argosy 24'

Gosman · 09-27-2010, 07:43 AM

Thank you
i will try and follow you instructions , as i told you every thing in the trailer was redone and the stove was removed for a while and once put back in i did turn on the tanks opened all the windows and lit all 4 burners .
But never tried to turn on the furnace .
Thank you so much for all your help.

Gosman · 09-27-2010, 11:19 AM

Sean & Sharon
'75 Argosy 24'
THANK YOU SO MUCH FOR ALL YOUR INFORMATION AND I DID FOLLOW ALL THAT YOU SAID ,OPENED ALL THE WINDOWS AND TURNED THE STOVE ON AND LET IT RUN FOR A WHILE THE TOP BURNERS SO AS TO PURGE THE SYSTEM .
THEN I WENT DOWN AND OPENED THE DOOR ON THE FURNACE AND OPENED THE WINDOW PLATE AND HELD IN THE OVER RIDE BUTTON THAT IS LOCATED ON THE SIDE OF MY UNIT .

SO WITH THAT SAID I HELD THE WHITE BUTTON IN AND I COULD NOT HEAR ANY propane or smell any ??
seams like the furnace is not getting any propane ?? any ideas ? stumped,
I looked under the trailer and it looks like every thing is turned on.
I DID TAKE OFF THE COVER PLATE ON THE OUT SIDE AND ALL IS CLEAR . HELP

wasagachris · 09-27-2010, 11:31 AM

Gosman while holding down the "override button" did you try to light it. Try using a bbq lighter(the long ones).

Gosman · 09-27-2010, 11:49 AM

Sean & Sharon
'75 Argosy 24'

FIRST I WANT TO SAY YOU HAVE VERY WELL WRITTEN INSTRUCTIONS , AND I FOLLOWED THEM TO A T .
AS WITH LETTING THE STOVE BURNER BURN FOR A WHILE SO AS TO PURGE THE AIR OUT OF THE SYSTEM , AS INSTRUCTED .

BUT AFTER HOLDING IN THE OVER RIDE BUTTON IN , I NEVER HEARD OR SMELLED ANY PROPANE. ANY IDEAS ,
I DID CHECK UNDER THE TRAILER AND ALL SWITCHES ARE TURNED TO THE ON POSITION TO LET PROPANE FLOW AMD I DID CHECK THE OUT SIDE COVER PLATE IS FREE OF ANY OBSTRUCTION.
ANY OTHER IDEAS

Gosman · 09-27-2010, 11:51 AM

WASAGACRIS----REPLY

while holding down the "override button" did you try to light it. Try using a bbq lighter(the long ones).

YES SIR I DID ?

wasagachris · 09-27-2010, 12:25 PM

Well to confirm if you have proane coming to the furnace you will have to slightly disconnect the line from the furnace and listen and smell for propane. First turn off the tanks(cylinders) outside. Light the stove to burn off any propane in the lines. You then loosen the connection of the propane line at the furnace. You will need two wrenches one one the fitting and one on the line so as not to break ant fittings or kink the line. Once the fitting is loose then turn on the tank(cylinder) and go back and check the fitting for propane(sound & smell). If you have propane there then i would suspect the gas valve of the furnace is faulty. Be careful to properly ventilate the trailer and not have any open flame nearby. If you don't feel comfortable I suggest you have a qualified serviceman look at it. Propane can be very dangerous if not handled properly.

Gosman · 09-27-2010, 01:18 PM

Sharbours and wasagachris

thanks for all your help you guys , i got the furnace running, i just had to hold the hold down a little longer than 5mins and she came right on .
One last question when it reaches the set temp will the furnace shut off and come on as needed to maintain the desired temp, that is the only thing i did not do . Only let it run for a short while because i am not sure how much propane i have in the tanks .

Again all thanks so much for all your help

wasagachris · 09-27-2010, 03:05 PM

Gosman yes as long as the pilot light is burning(light) then the furnace will start and stop as heat is required. If you run out of propane then you will have to light the pilot again. My water heater and furnace were pilot models originally. It's a lot nicer with the DSI (Direct spark ignition) models.

texascanuk · 10-06-2010, 08:23 AM

Here's a site for manuals for several different manufacuterers and appliances.

Service Documents

(I don't get any kickbacks)

My NT35K won't light, the fan starts when the thermostat is turned on, I hear the valve (or something) click and I see the spark through the view window. I have to check the burner orfice for mud dobber debris and rust debris. Is there any way to access the orfice without removing the furnace from the cabinet? I stared at it for a while and there doesn't seem to be a way to get into it other than removal.

Thanks,