The owners know when they are cold and they know where they are. They may not know how to turn on a pilot light, seal the attic floor, or balance a home’s heating system, but they do know when it’s cold. Bedrooms are usually the coldest room in the house, and most people just live in them. Put the child in the cool bedroom, put a couple of extra blankets on the bed, and tell him to finish his homework.
Dealing with a cool room is frustrating. If you turn up the heat to warm the room, the rest of the house gets too hot. Close all heating vents except the bedroom and exert too much back pressure on the oven. Too often I see a home trying to adjust the temperature in one room by closing the heating registers in other rooms and soon they have half of the house registers closed and the home heating system working overtime to meet the request. heating on the thermostat.
Typically, the home heating system is designed by a professional heating contractor who attended HVAC school for several hours a week for several years. A heating contractor must pass an apprenticeship program before he can even take the test for his officer’s license.
HVAC Education
During the educational phase of the heating and cooling training, they are taught how to calculate the heating load on a home. They take the heating load and develop a designed heating system that includes furnace size, fan capacity, duct size, airflows, and register size. In other words, heating systems are designed to heat all rooms evenly and to function as one system with all registers open.
If you have a bedroom that is cooler than the rest of the house, one of two things has happened:
- The heating system was designed by a contractor that just passed the test, or
- the heating system is broken.
Recently, a homeowner complained that too little air was coming out of his dining room heater register. The dining room was cooler than other parts of the house. With a flow hood, I recorded a 75% decrease in airflow in the register compared to the register in the living room. I removed the register grate, grabbed a flashlight and mirror, and looked into the heating duct.
With the mirror to see around the initial elbow, I could see that a flow regulating valve was installed in the heating duct. A closer inspection showed that all the heating ducts in the house had a flow regulator installed near the registers. The dining room hatch was the only one that was closed most of the way. The landlord was unaware that the flow regulators were part of the home’s heating system.
Heating duct damper
Flow dampers are a bit unusual in my wooded area, I don’t see them very often. Flow dampers are added to a heating system to allow manual adjustment of the air flow to the registers. With dampers, the air conditioning flow can be balanced to eliminate hot and cool areas of the home. To avoid putting greater pressure on the furnace fan motor, when one door is closed, another door must be opened.
Sometimes I think a heating contractor can put in a bunch of flow dampers when they drop their pencil and can’t be sure how big the heating ducts need to be or how many registers need to be in a room.
6 ways to increase the heat in a cold room.
Heating duct repair:
There is always the possibility that the duct system has a problem that can be fixed. The ducts can be partially or totally disconnected and the flexible ducts can be pinched or collapsed. This is the first and most important solution considering the cold room. This solution will not only heat the bedroom, but also increase energy efficiency and energy savings.
The first step is to inspect the conduit from plenum to register to make sure it is securely connected. Also, look for holes, bent or collapsed areas. Animal-damaged heating ducts is also a possibility to look for.
Disconnected heating ducts can be reconnected, but damaged heating ducts often need to be replaced as they are difficult to repair.
Check for a damper:
The astute heating contractor may have put a damper on the heating duct and kept it a pretty good secret. Look and feel inside the duct by removing the manhole cover. Also, remove the insulation from the outside of the duct, especially near the register, and check for signs of a damper. A metal rod with a small handle and some anchor bolts indicate a shock absorber inside. Open the hatch and your cold room problems may be over.
Balance room pressure with a crossover duct:
Now we have to talk about the pressure in the room and the balloons. Open the bedroom door about an inch, turn on the oven and see if pressure builds in the room and close the door.
The heating system is an air circle. Air is heated in the oven, pushed through the heating ducts into a room, and then sucked through the oven itself, out of the room, back through the return air duct to the oven. If the air in the room cannot return to the oven, the room builds air pressure, like a balloon, which restricts the flow of conditioned air into the room in the first place.
With an increase in pressure in the bedroom, the air conditioner passes through a different duct and enters an adjoining room.
To fix the potential problem, many homes have cross ducts installed in the ceiling or above the door that allow air from the room to return to the hallway even when the door is closed. In some larger, higher-priced homes, they may have eliminated the room pressure problem by installing a return air damper in each room.
To balance the pressure in the room and stop this problem, the two most commonly used repairs are to install a cross duct through the wall above the door or simply cut the bottom of the door so that there is a wider gap between the door and the carpet.
Increase the duct size:
Perhaps the heating contractor ran out of 8-inch ductwork, so he decided 6-inch was close enough. There is a real possibility that the back bedroom is cold because the heating duct system was not designed correctly. When this happens, the best solution is to correct the error and replace the conduit with a larger one. If the house is fairly new and the contractor is still around, you can do this as a freebee.
In this way, the cold room will receive more of the air coming from the oven. This repair can still be done by yourself if you are willing. The heating duct material, both ribbed and flexible, can be purchased at your favorite home store. A few cable ties, sheet metal screws, a sharp knife, and a pair of tin snips should do the trick.
If the size of the heating duct is simply too small to service the room, in addition to replacing the duct with a larger one, the only solution that might work is to install a booster fan in the duct or add a second full duct and record.
Duct Booster Fan
Place a baffle on the heating plenum:
This adjustment can be very effective, especially in a manufactured home. It is necessary to open a section of the main heating trunk (the plenum) to be able to place a metal baffle or shield in the main trunk line that directs more air into the heating duct that goes to the cold room. This is a very effective way to take more air conditioning that passes through the heated main trunk and direct it in the direction you want it to go. This is an inexpensive, permanent solution that works very well.
Install a booster fan in the duct:
This $ 30 part will not generate more heat, but it will draw more heat into the cold room. The booster fan should be installed as close to the room in question as possible and can be connected directly to the heater fan so that the booster fan runs every time the heater is turned on. Installing it can be tricky. A round metal conduit section must be dropped or added to the system. Make sure the duct system is air-sealed or this extra fan will draw unconditioned air into the system and reduce its energy efficiency.
I know dealing with a cold spot in your home can be a frustrating experience. I hope I have provided some solutions to the problem that will work for you and your home. Your home heating system was designed to give you the comfort you expect and deserve, and with a little love, it will provide years of energy efficient service.
Thanks for stopping by Detect Energy, I hope to see you again soon, but I won’t leave the light on … Don Ames
