Starting the 5.5kva Kipor diesel generator from a distance
If all you need to do is close a switch contact then install a suitably rated relay at the generator and operate it via a suitable voltage source and wiring. 

The power supply could be at either end.
If the generator has a battery (12V or 24V or whatever) used for starting then it can be fed
Battery+ve - Relay coil - one leg of cable switch at house -0 other leg of cable - Battery -ve.  

There are a very large number of relays available for any load liable to be required.
If operating from a battery then use a lower voltage relay coil plus a series resistor so that relay coil voltage will be correct when operated via wiring run and resistor.     

Example only:
Battery = 24V
12V relay coil = 240 Ohms so rated coil current = I=V/R = 12/240 = 50 mA.
To operate on 24V you need to drop 12V in the cable + resistor.
Say cable resistance = 60 Ohms.   (Very thin wire :-) )
REquired resistance = 240 Ohms (so half of 24V drops across 240 Ohm relay coil and half across R + cable.
R_resistor = Rwanted - Rcable = 240 - 60 = 180 Ohms.
Use a 180 Ohm series resistor (a standard value in this case)