At Over the Moon, we know how essential proper furnace installation is. The way your furnace is set up impacts comfort, safety, and efficiency. But how do you know the unit is properly installed and configured? That’s what we’re going to explain to you in this article. 

The Unit Is Cycling Normally

A furnace should turn on for 10 to 15 minutes and shut off when the desired temperature is reached. This means it is the correct size for your home. If the cycle time is shorter, parts of your home won’t be comfortable or the heat exchanger is overheating and triggering the high limit switch. The wrong-sized furnace or a dirty air filter can also shorten cycle time. For example, if the unit runs for just 4 to 8 minutes, it should be checked out.

Check the Temperature

First, check the thermostat you have. The set temperature and actual air temperature in the room should match. When they don’t, the furnace should kick in and run until the values are equal. A unit that runs when you’re not home is wasting energy, so if you are away often, invest in a programmable thermostat and set a temperature schedule to save energy.

Also, go from room to room and measure the temperature. If it’s consistent, then you have sufficient airflow. Otherwise, there may be an issue in your ductwork, such as a blockage, or a problem with how your furnace is performing. Contact a technician to determine the cause and make any adjustments/repairs necessary.

How to Do a Temperature Rise Check

A temperature rise check will show whether your furnace is set up and working correctly. Better yet, it doesn’t require special equipment or for you to be especially handy. To start, set the thermostat to “heat” and turn up the temperature ten degrees warmer than it currently is. The furnace should start running. Wait about 15 minutes.

During this time, the furnace should continue running and not shut off. If it turns off sooner, check the thermostat. If the set temperature has already been reached, the furnace may have been oversized. A furnace should not heat a room by more than 10℉ in under 15 minutes.

Once it’s been running for that long, feel the ductwork above the unit. It should be hot but not too hot to touch. To be on the safe side, stick a meat thermometer into the duct. This will provide a direct temperature reading.  

The thermostat’s location may also be an issue. If it’s too close to a heat register or heat-producing appliance, the reading can be incorrect. The thermostat can shut the furnace off prematurely and the area the unit is serving may not get warm enough. 

Calculate Temperature Rise

While you’re at it, check the temperature of the return air at the filter door. You’ll get different readings. Calculate the difference between them; this is called Delta T, also known as the “temp rise”. Every furnace has an acceptable temperature rise, unique to the model, that you’ll find on a label, whether it’s on the blower door or in the burner compartment. Temperature rise is usually expressed as a range. It should never be above 60℉.

Reasons for an excessive temperature rise include a dirty filter, low airflow, or a system problem. Schedule an inspection to determine if there are any problems or verify the furnace is set up correctly.

Check the Installation Report

Your HVAC installer should provide a written report after completing the project. It should detail all the steps an installer has taken, including balancing, testing, and any adjustments made. All components should be checked. The report should identify the testing, condition, and performance of each. Measurements of temperature, airflow, and electrical performance should be listed for future reference.

Call Over the Moon for Professional Furnace Set Up

When you need a new furnace installed, the licensed professionals at Over the Moon will make sure the work is done properly. We fully evaluate your home and provide energy-efficient options. In addition, our team manages all aspects of installation including mechanical, gas, and electrical. For more information or to schedule furnace installation, repair, or a tune-up, book service online or call 262-218-2842.