IRS will offset your federal refund,. Here is a copy of what is on IRS website question and answers.
Will I Still Get My Tax Refunds if I have an Installment Agreement?
As a condition of your installment agreement, any refund due to you in a future year will be applied against the amount you owe. Therefore, you may not get all of your refund if you owe certain past-due amounts, such as federal tax, state tax, a student loan, or child support. The IRS will automatically apply the refund to the taxes owed. If the amount of your refund does not take care of the tax debt; then your installment agreement continues until all of the terms are met.