Its the smaller one back by the fire wall, right above the condenser
You can not really recharge the water cycle, it is an ongoing natural process.
A smell coming from a reverse cycle air conditioner may be a signal that the filter needs to be cleaned. A smell like engine exhaust might be present if the air conditioner motor is in need of repair.
It sounds like you are low on refridgerant, i would have your A/C lines inspected, and maybe try to recharge it, could also be a bad A/C pump.
the air conditioning cycle
A reverse cycle air conditioner work like normal air conditioners only in reverse, transferring heat into a house instead of outside of one. It is not an air conditioner at all, but a heater.
infiltration
Infiltration
The equipment might have circuits which remain energised when it is in an off-cycle, but the energy used would probably be less than 1% of the energy used in the on-cycle.
Nickel Cadmium batteries can last through about 2000 recharge cycles.
4-cycle
If the engine has an oil sump and an oil filler spout, it is a 4-cycle engine. On a 2-cycle engine, oil must be added to the fuel.
If the key is in the on position and the engine is not running, the fuel pump is off. If the engine is running then the fuel pump is also. During the start cycle the pump will only run for 3 seconds unless the engine starts.