75,000btu unit?
This week my HVAC contractor upgraded my old oil furnace to a new 95% Ruud 2 stage heat/cool variable speed gas furnace. The unit itself is whisper-quiet compared to the old oil unit, but after about 15 minutes of running the exhaust vent starts gurgling and popping from condensation getting blown around from the power vent. Intake and exhaust are both stepped up from 2" to 3" at the unit, the pitch is good, the run is about 20' total in length and there are 5 short radius 90's. My contractor has been back a couple times checking for any blockage in the drain goin from the trap inside the unit to the condensation pump, everything is clear and water is draining fine to the condensation pump. Also, the amount condensation is a lot. I dont have a lot of experience with the 95+ efficient furnaces, and my contractor says everything is running the way it should. Is this noise normal? Here is a link to a video of the exhaust outside, where the noise is loudest from it echoing through the 3" pvc. https://skydrive.live.com/redir?resid=9ADF4CB14AA96C52!1754&authkey=!ABDQzII A_4wK8a8
75,000btu unit?
...
Gurgling usually indicates a sag in the PVC exhaust. Should run uphill all the way to the exterior termination. How far does it run from the furnace to the outside? Check and make sure it is all uphill, no sags.
Where the exhaust of the furnace exits the cabinet and the PVC vent connects,, there will be a plastic flange with (2) screws you can see it on the top. The pvc vent will slide into this. Is this connector piece white or black?
...
Are the drain tubes in the furnace all draining properly? An upward slope will trap water in the collector box or secondary heat exchanger.
The exhaust vent has over a 1/4 per foot pictch back to the unit. The total span is about 20 feet from the unit to the exterior. The exhaust is draining to the condensation pump but it almost seems like the volume of condensation is overwhelming for the 1/2 rubber drain hose inside the unit that migrates the water to the condensation pump.
Never heard that gurgle noise unless there was a sag in the PVC flue. They can product a lot of water but the hoses can handle it. That model has been out nearly 19 years, I put in a few of the test models including my sister's house. Can't get a much better furnace.
Could it be water In the inducer or is it gurgling out in the vent system? Is the furnace tilted forward slightly?
Tell your contractor to focus his attention on the white exhaust outlet tube. I cannot give DIY advice sorry. That is the reason I asked if yours was white or black as they have a different design. The unit may need to be "modified" and your issue will be resolved.
...