I was asked today to go do a Thermal Imaging scan for a local realtor who’s office I did a presentation for, he was complaining that the front bedroom and bathroom were cold and that he would like a scan done to check for insulation and air infiltration issues. I arrived at the house and turned up the furnace and could feel a noticable difference in airflow between the 2 rooms in question and the other vents. I told him I don’t believe you need an Thermal Scan here and walked in the basement and saw the supply lines to those rooms about 50 feet of run with 9 turns in the line and trying to push hot air downhill. I said I would post the pictures here to get some second opinions,but I believe he could try some inline booster fans to see if it could help his airflow, short of tearing open walls and re-running it I can’t see another way to do it. I scanned the walls at no charge to verify things looked OK but he didn’t need a scan he needs an HVAC technician that understands physics in my opinion.
If those pipes are supplies, I would seal the pipe joints with mastic, and then insulate with fiberglas duct wrap. An inline booster fan may be warranted, but I’d try the other first.
Let us know what finally works.
There is a sequence of testing needed to determine the problems and correct solutions.
Evaluate & Measure air flow.
Troubleshoot specific airflow problems including balancing airflow between rooms and between supply and return air.
Make necessary airflow improvements.
I would be using a duct blaster and a fog machine or smoke pencil/tube to determine the amount of duct leakage.
Find duct leaks and seal them.
(Using mastic and insulation are good solutions as suggested by Jerry.)
Consider insulating supply ducts.
Measuring duct leakage and airflow are the best ways of evaluating these two critical performance variables.
It looks like an amateur install on the supply pipes.
50 feet on supply runs is not a problem if they are sized right.
If those two separate lines in the pic are going to the same end of the house, the proper way to do it would have been one larger pipe, say, 12" diameter, then use a Y branch to two smaller runs.
I agree with David on the amateur part.
If access is not difficult, I would remove those supply runs and do it right, rather than using duct boosters.
Thanks for the replies guys. I agree the length of the run is alright. They are both supply lines, the left one supplies the main floor hallway which is not an issue. The one on the right runs down like you see then up to the second floor bedroom and bathroom all with 5 inch line. It runs along an exterior wall and over the front porch to the bathroom. In all likely hood not insulated through the entire route. He has arranged for the HVAC company that they use to come in and do a more detailed review of the system. He thought he had air infiltration and insulation issues and was pleased to get a better grasp on what was actually occuring. The shameful part is that this home is only 3 years old , the builder had the freedom to run the duct work a little better during the construction phase but now there are all these pretty finishes in the house making access pretty difficult now.