Looks like Warm front is no help in this case
"Financial assistance for improving energy efficiency in a rented property
The government provides some financial assistance to landlords and tenants to help improve the energy efficiency of
their rented properties.
Landlords Energy Saving Allowance (LESA)
Private landlords who pay income tax can offset up to £1,500 of spending on some energy efficiency measures (per dwelling, not per building). The qualifying measures are loft, cavity, floor or solid wall insulation, draught proofing and hot water system insulation.
To find out more, contact your local authority or HM Revenue & Customs (HMRC) enquiry centre. You can also find out about tax relief on property improvements on the HMRC website - Opens in a new window.
Warm Front
If you have tenants in England claiming certain benefits, they may qualify for Warm Front, a government scheme that helps people struggling to pay fuel bills. Grants of £2,700 are available (£4,000 if the dwelling has oil-fired central heating), but the tenant must make the application. The landlord does not need to be eligible.
Warm Front is not available to housing association or local authority tenants. Find out about financial assistance on the Warm Front website - Opens in a new window."
http://www.businesslink.gov.uk/bdotg/ac ... 1082194829
Perhaps you could see if your landlord knows about the tax relief above - he will have to produce an energy efficiency certificate to any new tennant in the future and having an inefficient boiler would count against him.