If it was a reserved ticket, cover letter plus ticket to
Customer Relations
Irish Rail
Abbey Street
Dublin 1
Given reason as delay, train cancelled or left standing despite reservation. Refund in case to the credit/debit card used.
Otherwise
http://www.railusers.ie/passenger_in...ty_heuston.pdf
Again to
Customer Relations
Irish Rail
Abbey Street
Dublin 1
Refund in vouchers, only valid for booking office transactions