Humidity – Essick Console vs Aprilaire 500
Cold edge of Zone 4. New construction with above average insulation. About 5,000 sq ft/64,000 cu ft conditioned space on two levels, each with its own HVAC and one ERV interconnected to both HVAC. ERV runs 24×7.
In winter, mostly only use heat from downstairs and in summer, only use AC upstairs with portable dehumidifier downstairs. Blower door rated at 2.41 ACH50. HERS Index 21.
Both furnaces have Aprilaire 500M humidifiers connected to the hot water line of a tankless gas heater. They operate only when the furnace runs, which is not that often.
I have an Essick H12 console evaporative type humidifier with stat that puts out about 8 gallons per day and keeps the whole house at humidity levels up to about 45%. Only downside is some low fan noise in the family room/kitchen (well, maybe re-filling the 2.5 gallon tank 3 times per day). Humidity is evenly balanced throughout both floors of house (presumably through ERV and/or large stair opening between floors).
I have not used the Aprilaire yet, other than to check they work. Intuitively, it seems the Aprilaire, with usually only the downstairs furnace running less than continuously, the console is more effective and at least equally energy efficient.
The console says it uses 2.2A, I haven’t tested it. So, it’s running this 24/7 vs intermittently firing up the tankless gas repeatedly (wear & tear) and unknown quantities of un-evaporated water going down the drain. Both need once per year filter changes.
Admittedly, I don’t know how well the Aprilaire would humidify. That said, any thoughts about the Aprilaire vs the console for comfort, tankless gas wear & tear and energy efficiency?
Second question. I set the humidifiers per commonly found temperature & humidity charts:
+40 = 45%
+30 = 40%
+20 = 35%
+10 = 30%
+ 0 = 25%
-10 = 20%
-20 = 15%
My understanding is this chart is to prevent condensation on windows, etc. Nonetheless, even at +10 and humidity set at 40-45%, I get no condensation. Humidifier is only a few feet away from a whole wall of double-pane glass (Pella Impervia Fiberglass). No sign of condensation at all.
Can I keep humidity at higher levels than chart recommends if there is no condensation? Thanks.
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