There’s an argument to be made for cleaning your heat registers…actually, there’s several.
First, there’s the energy argument. In theory, especially in forced air systems, air flow is reduced as heat or air registers become clogged and otherwise dirty. Anything that reduces airflow has the potential for jacking up your energy bills because the furnace (or a/c for that matter) has to work harder to attain the desired room temperature.
And for non forced air heating systems (radiant heating for example), if the heating apparatus is dirty, the furnace (or heat source) …

One of the most challenging problems for homeowners is with the placement of a heat register, radiator or other heat source under or near a window. The problem is compounded with every degree the temperature plummets outside.
Understanding the problem
To figure out how to fix the problems, we have to understand what is going on. Warmed air always rises (and conversely cold air falls). Since warmed air will always rise from the heat source it will gravitate upwards. Under most circumstances, when a heat register is on a wall, the warmed …

When you are buying a new home, here are some things to look for to ensure you keep your energy bills low:

Look for energy efficient appliances. Most of the time they will still have the energy guide sticker on them. Check the efficiency and relative costs.
Check the age and condition of the delivery ducts and vents
Ask what the last HVAC job was. If someone installed central air or a new furnace after the home was built, there is an excellent chance the installer did due diligence and inspected the house …

This one puzzles the heck out of me.
We’ve talked about how a lot of heat escapes through the windows. Heat vents blow heat into a room. Why then, would anyone place a heat vent directly under a window?
Argh!
A lot of heat will be wasted, and the room will always feel colder than it should.
Luckily, there is a very easy solution.
Go to your local home improvement store (like a Lowe’s or Home Depot) and get a clear heat deflector. They run $5 – $15. These have little magnets on …