Families in 'fuel-poor homes' are in danger of losing up to £50 million in grant funding, according to GAIN.
GAIN believes there is a danger that some of the £50 million Warm Front budget currently allocated to improving the heating and insulation of 25,000 of the most deserving fuel-poor homes.
This is because the grants are not being taken up fast enough, due to tighter, more restrictive criteria imposed this year, as well as a lack of public promotion, with many of the most in-need families unaware that they qualify.
The warning comes days after the latest fuel poverty statistics were released, which said the number of households in fuel poverty had fallen in 2010, but are expected to have risen since.
Applications need to come in within the next six months for installation by the 31 March 2013 deadline, or the allocated funding reverts to the Treasury.
GAIN is asking the Department of Energy & Climate Change (DECC) to promote the scheme widely through local authorities and housing associations, so both they and the needy are aware of the grants now available.
The Association is also asking the government to review the scheme criteria to ensure that all the grants are allocated to more needy households.
Meanwhile the Association urges registered social and private landlords to publicise the grants to the general public with notices in libraries, citizens advice and energy advice centres. Potential recipients may also contact members of the Grant Aided Heating Installers Network to see whether they qualify.
Warm Front is due to end in March 2013, following the introduction of the new Green Deal, underpinned by the Energy Company Obligation, focussing on hard-to-treat homes, the vulnerable and the fuel poor.