have 77 barth 21' 454..furnace is a nt30 discontiued model...anyway was working for about 30min..quit blowing hot air...when thermostat is raised blower comes on but no clicking noise...have ohm/volt meter..any suggestions on what i might possibly check for..thanks roy

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77 21' 454
livin in beautiful southern illinois

I have a '77 Suburban NT30 owner's manual that has a diagnostic decision tree...give me a fax/snail-mail contact for a copy if you don't get answers here......

I am looking through the CAMPERS CHOICE catalog and they have SUBURAN FURNACES NT SERIES The NT30SP looks like the one I have in my Barth.

Ralph Glover

Roy,

Via snail-mail, I've sent you a Xerox copy of the Suburban NT30 furnace manual, circa 1978....

In the meantime, there's some good generic info about furnace troubleshoooting at:

http://www.dinosaurelectronics.com/Tips_Tricks_Page.htm

(Warning: If it's circuit board type problems, requiring replacement, the prices I received from dinorsauerelectronics came awful close to trashing-out the old furnace and starting from scratch with new.....)

I bet it is the ignitor board. I replaced mine and it fired right off. My old furnace in my 72 had a bad gas valve and it came close to blowing the front of the furnace off. Be real careful when working on these things. I think that it is best to bench test it before you install it in the motor home. Be sure and check the sail switch and make sure that it is doing its thing. You can do that with a meter. Dennis

thanks to all the suggestions..and for the copy in the mail..will wait till it warms up a few degrees and check it out..merry christmas to all

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77 21' 454
livin in beautiful southern illinois