My sister just purchased a lovely single family home in the DC area. The house has radiators for heat. When she viewed the house in June (checking the thermostat and all) there was heat. The move-in was a week ago and now there is no heat. I believe she has a boiler associated with the hot water tank. There is hot water but no heat. How do we turn the boiler on and/or the radiators to gain heat? Help!