Have your heating system cleaned and tuned by a qualified contractor. A pre-season tune-up and filter change is a good investment. It reduces the chances of breakdowns in the middle of winter, improves safety, and pays for itself through more energy efficient operation.
Warm vinegar will generally soften the most stubborn old glue on old furniture. Dipping the parts to be reglued in warm water, and then letting them dry out completely, will help to open up the wood pores and allow the new glue to enter the wood more freely. Warming the parts on top of a heater or in the sun will also help open up the pores of the old wood before regluing.