The TRIAC is an electronic component on the printed circuit board (PCB) module.
If you want to tackle a repair, firstly, check for breaks in any of the wires in the loom to the motor and also the motor wiring connector.
If all OK, the most likely cure seems to be to replace the PCB. However, new PCB modules need to be programmed to your model of machine.
You can buy reconditioned PCB's from EMW Electronics (and possibly other suppliers) which are pre-programmed, but you need to be very careful when identifying your current PCB & machine model and then follow the ordering instructions so that you obtain the correct replacement board.
I'm not a service technician though, just going by what's been said in other threads on the topic.
If you need to find a tradesperson to get your job done, please try our local search below,
or if you are doing it yourself you can find suppliers local to you.
Select the supplier or trade you require, enter your location to begin your search.
Please select a service and enter a location to continue...
Are you a trade or supplier? You can create your listing free at DIYnot Local