What causes caravan aircon to trip circuit breaker on start up

There can be several reasons for this, the sensors issue, circuit issue and ac issue also can be, i had a simmilar issue in my towing truck which we are using for Long Distance Towing services, so when i make that audit so there was a sensors issue. Now i am using that truck in a Rite way towing https://www.ritewaytowingnyc.com/

You don't give enough info, but I presume you mean the breaker on the parks supply post trips?
If so it means you have a dead short somewhere in your RV, the only way to find out what and where is to turn all the breakers on the RV board, turn on the master first, it should stay ON, (See note) proceed to turn the other breakers "ONE BY ONE", one of them should jump your or the park's main, keep that one OFF until you identify and repair the shorting equipment in your RV.
(Note if the parks breaker jumps when you turn on the RV's main only, get professional help.)

Try these places

http://www.rvpartsnation.com/rv-heating-cooling/rv-air-conditioner/dometic-air-conditioner/dometic-air-conditioner-parts/dometic-quick-cool-ducted-return-air-grill/?gclid=CLn8rMiR0M8CFYgvgQodw_kKOg

http://www.adventurerv.net/dometic-air-conditioner-return-air-grille-center-duct-p-28803.html?gclid=CKSnz_yR0M8CFY4vgQodnAgNrQ&utm_campaign=partsfeed_ppc&utm_medium=cpc&utm_source=Froogle

13.8 volts need to be applied to the batteries to charge them. The loose button you refer to is the circuit breaker for the inverter. when it trips it pops out and is not loose any more.

120-
VOLT
AC
SYSTEM
The following electrical components (if so equipped) will only operate when your
RV is connected to shore power: 120 to
12-volt power converter, air conditioner,
120-volt refrigerator, microwave oven, television(s), fireplace and appliances
plugged into convenience receptacles.

SECTION 6 - ELECTRICAL SYSTEM JAYCO TOWABLE
6-2
120-
VOLT
CIRCUIT
BREAKERS
The 120-volt AC circuit breakers located in
side the main load center protect all
120-volt wiring and components in the RV fr
om circuit overloads and short circuits.
Should a circuit overload or short circui
t occur the circuit breaker protecting the
affected circuit will "trip" preventing the flow of electricity through that circuit.
If a circuit breaker trips, shut "off"
the appliance on that circuit (i.e., power
converter etc.) and allow the circuit breaker to cool down for a brief period of time.
After the cooling down period, reset the circuit breaker by moving its lever "off" and
then back to the "on" position. If the circuit breaker re-trips or frequently trips,
contact your dealer to have the electrical problem diagnosed and repaired.
A circuit breaker identification label is permanently attached to the inside surface
of the 120-volt load center.
Maintenance and Replacement
At the beginning of camping season, inspect the circuit breakers and replace as
needed. Test by turning each circuit breaker "off" and back "on". Circuit breakers
are wearable parts and must be replaced
as needed, as part of your RV
maintenance. If you have any questions, consult your dealer.
Please contact your dealer for repair assistance when replacing circuit breakers.
CONVERTER
The power converter converts 120-volt AC power to useable 12-volt DC power
when the shore power cord is connected to an external power source.
The converter has a built-in protective thermal breaker that will shut it down should
overheating occur. Overheating can be
caused by operating the converter above
its maximum power output for an extended period of time, or by an obstruction to
its ventilation air flow. To reduce converter heat build keep unnecessary 12-volt
lights and motors turned "off"
.
Keep the converter cooling fins and fan clear of
obstructions.
Inspection and maintenance
If the 12-volt power converter is not working (auxiliary battery not being charged)
check the reverse polarity fuse(s) in the converter fuse panel.
There are no
customer serviceable parts inside the converter case and the
manufacturer's warranty will be void if
the case has been removed
. If you
have further concerns contact your dealer.

FUSE WAREHOUSE HUH? oK, IF FUSE REPEATEDLY BLOWS, GLASS TUBE? CORRECT? tHEN YOU HAVE A SHORT CIRCUIT OR ACIRCUIT OVERLOA.D. tHE PUMP MAY BE TAKING OUT THE STEREO BECAUSEPUMPS PULL AMPS WAY MORE THAN PRETTY MUCH ANYRHING ELSE.. The pump should have a dedicated circuit. Or remove anything piggy backing on the pump circuit and bump the fuse 5 amps. Here is a trick of the trade. Go to autozone and chk out the AUTOMATIC CIRCUIT BREAKERS. bUY ONE THAT WILL FIT WHERE THE FUSE WENT.dO NOT GET THE SAME AMPERAGE. IT WILL FLUTTER LIKE A TURN SIGNAL FLASHER. NOT DESIRED BECAUSE WHILE THE BREAKER KEEPS ON AND OFFING, yOU WILL HAVE THE TIME TO REMOVE SUSPECTED WIRES. wHEN BREAKER STOPS TRIPPING, YOU HAVE FOUND THE PROBLEM CIRCUIT. tO SLOW DOW THE TRIPPING OF THE BREAKER, GET A HIGHER AMP BREAKER. bUT! dO NOT BUMP IT UP MORE THAN 5 AMPS AT A TIME OR THE RISK OF OVERHEATING YOUR WIRING SOARS. i ALWAYS HAD SOMEONE ASSIST AND WATCH FOR PROBLEMS LIKE WIRES HEATING UP, SMOKE OR SMELL. i DON'T MEAN TO SPOOK YOU, BUT YOU ARE BYPASSING THE DESIGNATED THRESHHOLD BY USING AN ALTERNATE TYPE OF CIRCUIT BREAKER WHICH RAISES THE THESHOLD IN ORDER TO DETECT AND LOCATE YOUR PROBLEM. iF THE
BREAKER CLICKS RAPIDLY, YOU HAVE A DEAD SHORTsLOW ORWIDELY SPACED TRIPPING MEANS YOU HAVE AN OVERLOAD SITUATION(TOO MUCH DEMAND ON THAT CIRCUIT. iF YOU WANT, AFTER ALL IS SAID AND DONE, TO USE AUTO CIRCUIT BREAKERS, gET THOSE OF THE SAME AMP RATING AS THE GLASS TUBE(BUSS FUSE. tO ME, THE METAL CASED ONES ARE FLAME PROOF WHERE PLASTIC MELTS .. tHEY AREN'T CHEAP BUT WORTH A TON OF BUSS FUSES. gOOD lUCK AND BE SAFE - T tHANKS FOR USING FIX-YAED NED-

There is an in line circuit breaker that controls the power for the slide. They are automatic resetting. Sounds like it is tripping but once it cools down it resets. They do get weak with age/use.

First thing to check is make sure hydro breaker in panel is not tripped or in the off position. Once you check that power is on to it, turn temperature down and put thermostat on auto and cool and see if anything happens. If it doesn't start up, listen for clicking or any other noises and report back to me.

Sounds like the element in the tank is shorting to ground thru the water in the tank. Disconnect power, the remove cables from element connection and protect them from contacting anything. Turn on breaker again. If it does not trip replace element or entire tank. If it continues to trip it's somewhere in the harness or a bad breaker.

Your AC (air conditioner) would only run on AC (alternating current - shore power) so there would be a circuit breaker. Fuses are for DC (direct current - batteries).

That said, 16A is a very odd number for a circuit breaker (or fuse).

Your AC will only run if you are connected to shore power or have a generator. (Very large inverter and a lot of house batteries is technically possible but very unlikely and it wouldn't have been built that way).

If your AC actually draws 16A then being connected to a 30A outlet is fine, I have actually connected mine to a 20A outlet at home to test it but I made sure nothing else was turned on fridge, heaters, water heater etc).