variable speed AC

mjryan0400

I recently had a Lennox iHarmony variable speed system installed. Was working great, however, they did not correctly install the dampers. They came back and fixed the dampers, however, it now feels like we do not have the benefits of a variable speed system. The air is either blasting out or the system is off.

The Blower CFM Demand appears to only have 3 levels - 0, 1066 and 1300. After it runs at 1300, it cuts back to 0 until it turns on again. Cycle is 0, 1066, 1300, 0.

I was expecting a lot more variability in air flow to maintain a constant temperature. Are the above numbers reflective of a system working correctly?

EdTheHeaterMan

This will depend on the equipment that the zoning controls are connected to. Post the model number of the outdoor unit and the indoor air handler or furnace to verify that it is a compatible with iHarmony zone controls

EdTheHeaterMan

From the literature I have reviewed, the iHarmony zone system can work on systems with variable output and 2 stage output. If you have a variable speed compressor then your CFM should be different based on how many zones are calling. it sounds like there are some installer programing adjustments needed to get the system to operate to a higher performance. That may be an air handler/furnace adjustment or that may be a zone panel adjustment. You will need to get in touch with the installing contractor and ask that a technician that has taken the Lennox Factory Training class on this equipment be the one to set up the system properly.