This problem can be easily fixed. Simply locate the air intake vents for your furnace of your house. Take a dryer hose from the intake vent to your grow room, and block the intake vents of your house. Direct the dryer hose up high, to suck out the air from your grow room and distributed it throughout your entire house.
By filtering the heat through out your house, it will not make a significant change in temperature. Just think of the 1500 want heater and imagine it heating your whole house, even in the summer. Simply not going to happen. Furthermore, seeing that the HPS light does not utilize the full 1500 Watts of power produced the heat, a lot of the energy is being directed into creating light. This is a comparison of a 1500 W heater which is very common, and comparing it to an imaginary 1500 W HPS light. Most growers use anywhere from 400 W to 1000 W so the heat production is most likely insignificant when its distribute it throughout the house. And the beauty of this system is that the thermostat in the house, can regulate the temperature. Either it be cooling or heathing the house, or both.
And if the grow light is causing too much excessive heat, you can easily set your thermostat to air-conditioning mode and to regulate the temperature of your house, at a steady level. Or simply open up your windows in the house to vent out the heat. And of course on cool days you can close your windows. Or you can open your windows and set the thermostat on your heater to the right temperature to make it look more normalized. Then you don't have to ever worry about helicopters or police officers detecting your grow operation with FLIR. As the air-conditioning system can easily cool your house off.
A quick note. Instead of purchasing a carbon can filter, you can simply go to Lowe's and purchase a carbon air filter for your furnace! This even saves you more money. It's a beautiful system!
This system is based on the idea that you're growing in the basement. As you have easy access to the furnace air intake duct work.