Shutting registers for temperature control seems logical enough. After all, you’re just closing off a room that you don’t want to send air conditioning or heating to, right? Seems like a good way to save money on your utility bill.
The reality is that shutting registers for indoor temperature control may do just the opposite — that is, cost you more on your utility bill. Furthermore, you may even be harming your HVAC system when you block off a register or vent. Here’s why.
Why You Shouldn’t Block Registers
Your HVAC system was sized to produce a certain volume of conditioned air for your home. When you block off a register, the HVAC is still producing that same volume of air, but the air meant for the blocked-off room can’t go where it needs to go. Under pressure, it will leak out around doors and windows, into the basement, out of unsealed ducts or even into floor cavities. Unfortunately, you’re paying the cost for heating or cooling air that’s now leaking to the great outdoors or into unconditioned spaces.
And then there is the matter of blocked return registers. As the HVAC tries to draw in return air, it can’t find the return air it needs in the blocked-off room, so will start pulling in air from outdoors through those same cracks around doors or windows, rather than from inside the home. Pulling in unconditioned air as return air means your system has to work harder to heat or cool.
Other Problems Blocked Registers Will Cause
In addition to your HVAC system running inefficiently, blocking registers can cause other problems, such as these:
- With reduced air flow, the furnace heat exchanger may overheat and crack.
- With reduced air flow, the evaporator coil may freeze, preventing refrigerant from returning to the compressor and causing it to break down.
For more on indoor temperature control, contact Ace Hardware Home Services of Dayton.
Our goal is to help educate our customers in Dayton, Ohio about energy and home comfort issues (specific to HVAC systems).
Photo credit: iStock.com/Eoneren
