Saw your letter on the list... I'm having the same problem, i.e.; good AC, DC
operaton, and it does light on gas, but doesn't cool.  After numerous
discussions with the Dometic service techs in Indiana, and having cleaned
every orifice, and spot on the unit,  I'm sure it's the 2 stage thermostat.
 It operates on low flame only, and doesn't kick up to high flame on max
cool.  This is symptomatic of a bad thermo..  On high flame operation, you
should hear a pretty good rumble in the vent plate if you get ;your ear
somewhat close.  My other units all have this type of operation.  I've
ordered a thermostat $126.00 from a local RV repair and parts service that
Dometic recommended, so I should be operating by next week.   If it's not the
thermostat, I'll post it to list, but I'm pretty certain (126.00 worth) on
this one... Hope you find it's the same type problem, because this is cheap
fix versus RV repair shop bill, or new fridge!..

Ron Katz,  Owner of White Cloud (89 Westy), and Proud Caretaker of Mikey, The
Genuine, Original, Ozark Mountain Wonder Dog and Griz Chaser.