Whole house dehumidifier to replace HRV?
Are there any whole house dehumidifiers (WHD) that can do balanced ventilation and replace an HRV? Or any that can work with an HRV to use the same ducting? I’m not 100% set on going with a WHD, just trying to see if it’s even an option right now so I can do further research.
Thanks
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Ultra Aire makes combined ventilators and dehumidifiers. They can be incorporated with the air handler on a conventional HVAC system. I had a 98H on my last house and was satisfied with the performance.
Thanks for the reply. I don't have an air handler though, I have baseboard electric and ductless heat pumps. That's why I'm asking about incorporating a dehumidifier with my HRV as that system is the only duct system in the house.
Whole house dehumidifiers typically need higher airflow than an HRV. Not impossible, but it adds complexity if you want to create your own combination.
Probably worth it to measure how well mixed your house is with a portable dehumidifier or two and open interior doors.
Jon R,
Thanks for the reply and information.
Could you explain how that measurement is completed?
Just walk around with a humidity meter and check.
Thanks
Note that a lot of humidity meters respond slowly, so I would say it's more like take it somewhere, leave it there for half an hour or more, note the reading, move it again, etc.
Depending on the season and the climate, a combination of a dehumidifer and an ERV instead of an HRV can be good, and can help avoid the need for ducting, or much ducting, of the dehumidifier. During high outdoor humidity conditions, with the indoor humidity kept low by dehumidification, the air delivered by the ERV will be much lower humidity than air delivered by an HRV. The HRV combined with single-point dehumidification can lead to high humidity where the HRV is delivering air, but ERV greatly mitigates that problem. I wouldn't quite say that the ERV distributes the dehumidification around the building--it's more than it avoids having the HRV create humidity hot-spots.
If you have an HRV with the option to swap cores for ERV, that's easy. If it involves buying a new unit, that's a harder pill to swallow.
The dehumidifier could be a stand-alone portable unit, or a ducted unit with just one supply point and one return point. Or maybe two supplies, depending on how easy it is to install them and the layout of the rooms.