diagram illustrating a heating apparatus in accordance with an embodiment of the present invention the heating apparatus is applied to the chamber 30 for hastening the performance of raising the chamber temperature to a specific temperature the heating apparatus includes a heater 32 and a gas supply apparatus 34 the heater 32 is configured on the upper position of the interior of the chamber 30 to heat the whole air enclosed in the chamber 30 and the gas supply apparatus 34 is connected with the chamber 30 to supply the dry air into the chamber 30 continuously if the chamber is a test chamber the gas supply apparatus infuses the dry air laterally into the chamber and if the chamber is a preheating chamber the gas supply apparatus infuses the dry air downwardly into the chamber form the top of the chamber no matter what the direction of the dry air infused the infusion of the dry air will change the air flow of the chamber and increase the interior pressure of the chamber to push out the air which carries water in another embodiment an exhauster such as a fan is connected with the chamber to hasten the exhaustion of the air enclosed in the chamber to sum up in the present invention the dry air is infused into the chamber to change the air flow of the chamber and some portion of the air enclosed in the chamber is pushed out due to the increase of the interior pressure of the chamber and so that the heater can raise the chamber temperature to a preset temperature and then to obtain an isothermal environment in a short.