hi there
if connect this thermostat to 5x12v at 1.25amps will it work ok?
Please elaborate as we have no clue what you are trying to do.
i want to keep my pigeon loft at 21c buying doing this i will need to hook it up to a thermostat so when the temperture hits 22c the fans will start and get fresh air in to the pigeons
Final attempt:
Regardless of your application, what is the voltage and current that you want to switch ?
i have a power supply of 12volt 2amps max i have to control 5 fans rated at 12volt dc at 0.25amps each they will be connected together moking it 12volts 1.25 amps out put i want to know what ampage does this kit hold without over loading it?
if you dont understand still i give up 
Should not be a problem.
If you look at the kit specs, you will notice it can handle 3A