If you purchased your furnace in 2010 and you’re a National Grid customer, you may be eligible for National Grid’s Residential (Gas) Energy Efficiency Rebate Program. To apply, download, complete and send in this rebate form.

However, if you installed your furnace in 2009, rebate forms are no longer available online, so you will need to call the program helpline at (866) 716-8099 to find out if you can still apply.

Also, be sure to check out the Federal Energy Efficiency Tax Credit. Depending on your furnace’s efficiency rating, you may be eligible for a tax credit equal to 30 percent of the cost of the furnace. If you bought your furnace in 2009, make sure to claim the credit on your 2009 tax return.