Hyperbole of “balanced ventilation”
“Balanced ventilation” is just not making sense. ERV/HRV’s with same air volume in as out are “equalized” settings, not “balanced ventilation”. Here’s why:
Infiltration/exfiltration is a fact of even the tightest house – even passive’s (doors and windows jambs, range hood, dryer and bath fans, boiler and DHW vents/supply, cellar and attic doors)
– Woodstoves when fired are draws; when shut down are either incoming or outgoing drafts; and in certain seasons and weather are wind tunnels.
– Atmospheric pressure, natural house stack effect, prevailing winds causing +/- pressure differentials, exterior convection; mass features, emittance and heat retention, north side/south and high/low building features and temperature differentials.
– No house is in equilibrium, nor is any a closed system, so “equalized” settings in an ERV/HRV is not balanced ventilation. Balanced ventilation would be a solution that responds to pressure changes and the need for make-up air. Passive vents can do this. Pressure and volume regulating in/out air flows in fans and ERV/HRV’s might do it . Where do you find those in residential technology or design.
Stop misleading folks into believing ERV’s and HRV’s balance the atmosphere in a house. If anything, positive over pressure makes more sense to achieve balanced ventilation.
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