Ok, you have owned the house for 2 years but moved to the U.S. 7 months ago. Was this house your PPR before you left?
If it was your PPR until 7 months ago, then you can sell now and shouldn't be liable to CGT on the profits. Owner occupiers get a 12 month deemed occupancy grace period in which to sell after they move out without being liable to CGT.
However, you are still liable to income tax on your rental income. Only the interest part of the mortgage payment is a tax deductable expense, so you may have a taxable profit even though the rent doesn't cover the whole (interest & capital) mortgage payment.
Also, if you paid reduced stamp duty when you bought the house due to being an owner occupier you will be liable to clawback of stamp duty due at investor rates, which would have been due to be paid when you started rented out the house.
Check out the property investment forum on this site and the Revenue link in my previous post for more information.