Massachusetts lawmakers have once again increased the amount of funding available to low-income residents who rely on fuel assistance programs to heat their homes. The latest infusion of cash means the Tri-City Community Action Program , Inc. is distributing an additional $900,000 to households in need. State housing officials said a boost in federal funding made the increase in home heating assistance possible. However, even with the additional funding, the state is still doling out less money to fuel programs this year than it did last year, when heating costs were lower. Tri-CAP was allotted $2.1 million in December, down from $5.2 million in 2010. Since then, there have been two increases in federal funding for the fuel program - one just before Christmas and the most recent increase on Jan. 4, bringing the total amount earmarked for Tri-CAP to $3.7 million. In addition to Stoneham, Tri-CAP serves households in Everett, Medford, Melrose, Winchester, and Woburn.