Sorry but nearly all RV manufacturers, including FR, only provide a generic owners manual.
No such thing as brand or model specfic manual.
Get the brand/model # of furnace and go to their website to download the furnace manual.
Just so you know, 1999 was the first year FR made a hybrid, in Roo/Shamrock lines.
and Zoe the Wonder Dog(R.I.P.)
'07 Roo 23SS pushing an '07 Chevy Avalanche
Equalizer WDH and Prodigy BC