correcting new construction install of HRV and dehumidifier
We recently bought a new construction home in zone 7. In addition to the standard HRV the builder provided, Fantech flex 100H, we had them install a whole-house dehumidifier, Santa-Fe Ultra120.
Our goal was to manage humidity in the summer, late-summer/fall especially when it is humid outside but not hot enough for the air conditioning to run. We told the builder that we wanted to dehumidify the outside air before it came into the house to achieve our goal.
We are seeing the system not reach the programmed humidity level of 45%. The house currently is at 48% humidity. It is cool outside so the air conditioning is rarely running. The outside air is also more humid (60%) than the inside air. It looks like the system is not working to get to the set humidity level.
We have been looking over the configuration and are not seeing how the dehumidifier is being effective as it is ducted. We are wondering how this can be corrected to effectively manage humidity? Pictures are attached.
Currently the HRV appears to have its own set of ducts independent of the other systems. The exception being the fresh air output duct may go into the HVAC air handler supply (it’s above the ceiling so hard to see). The Santa-Fe has an intake duct coming from inside the house somewhere and the output from the Santa-Fe goes into the HVAC air handler supply. See photos. The right duct into the Santa-Fe is the intake.
So it would seem in the current configuration that the HRV would run independently on its air exchange cycle bringing in that more humid air. But we are not seeing any active dehumidification taking place (the fan is not running on the HVAC on its own). The dehumidifier has run at some point as there is a little water in the drain hose. Can this be corrected?
Thank you in advance for your advice!
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