Service & Maintenance / Extra Edition

Troubleshooting Challenge: A Furnace That's Not Heating the Whole House

Figure 1. (Click on the image for an enlarged view.)

In our troubleshooting situation this time around, we have a customer who is complaining about one of the bedrooms in their home, specifically that the gas furnace doesn’t warm the room properly. When you arrive, you find that the bedroom in question is the furthest from the furnace, and that the duct system being employed is an extended plenum system like the one shown in Figure 1.

In your overall survey of this situation, you find that the customer has been trying to force more air into the back bedroom (shown at the top right of our duct system) by closing off other registers with cardboard and duct tape, which didn’t help the diminished airflow into the problem room. You also note in your evaluation that the return air system that employs a return grille in each room is operating properly without restriction in this ranch style home on a concrete slab.

Figure 2. (Click on the image for an enlarged view.)

As you begin your detailed evaluation of the equipment, you note that the manufacturer has specified a temperature rise of 55 degrees, and your temperature rise test shows a difference of 60 degrees. You decide next to check the operation of the blower motor, and note (as shown in Figure 2) the wiring connections.

Your troubleshooting question: What is the next step you need to take in solving this problem?

Compare your answer with ours by clicking here.

Publication date: 11/09/2009

Did you enjoy this article? Click here to subscribe to The NEWS Magazine

Recent Articles by Jim Johnson

You must login or register in order to post a comment.



Image Galleries

2015 ACCA Conference

Images from the 2015 ACCA Conference in Grapevine, Texas. Posted on April 8, 2015.


NEWSMakers: Clint Schreck

Clint Schreck, general manager, Columbus Worthington Air, Columbus, Ohio, discusses winning Angie’s List Super Service Award, how to handle online reviews, and much more.

More Podcasts


NEWS 05-18-15 cover

2015 May 18

Check out the weekly edition of The NEWS today!

Table Of Contents Subscribe

Legislation and Regulation

What legislative/regulatory issue is most important to you as a HVAC business owner?
View Results Poll Archive


2015 National Plumbing & HVAC Estimator

Every plumbing and HVAC estimator can use the cost estimates in this practical manual!

More Products

Clear Seas Research


Clear Seas ResearchWith access to over one million professionals and more than 60 industry-specific publications, Clear Seas Research offers relevant insights from those who know your industry best. Let us customize a market research solution that exceeds your marketing goals.


Magazine image
Register today for complete access to Get full access to the latest features, Extra Edition, and more.


facebook icontwitter iconyoutube iconLinkedIn i con