AdministratorApril 10, 2022 at 9:48 am
@jonfkleingmail-com The concern that the engineers expressed was over exhaust fumes being sucked into the ‘house’ air intake. The answer expressed by the experts was to separate the intake from the burner’s exhaust. It was done – I have lived in top floor apartments in two of our three buildings where the output from the MUAs is strongest. I installed CO2 detector/alarms in our apartments, and have never been ‘alarmed’. Success?
The underlying problem we had was that the 1979 vintage MUAs did not provide sufficient hallway pressurisation to ensure smoke from an apartment fire would exit the windows rather than enter the halls, so we needed to upgrade the hallway pressurisation. Odour (cigarette smoke, cooking) was also a problem, but from apartment to apartment. When the wind was strong and windows were open, the pressure on the windward side of the building could overwhelm the MUA pressure in the hallway, so odours crossed the hall into apartments on the leeward side of the building 🙁
The taller air intakes to the MUAs do indeed look strange. One sees them building-to-building. From the ground, they are not so noticeable on our eight and ten storey buildings.
If you lower the MUA air intakes, they will be at the same height as sewer vents and exhaust fans from the bathrooms and kitchens (if they are ducted upwards, as ours are). That could be a new problem.
I think that since our work was done, the companies have changed and I do not recall the name of those who did the work around 16 years ago. I suggest you consult APEGA or the Canadian Condominium Institute – Southern Alberta chapter for professional members specialising in this type of work.
Take a look at the (now old) Green Condo Guide from the Pembina Foundation. It doesn’t mention ERVs particularly (they have improved since then). You might also find this article interesting: Largest Passive House Retrofit in Canada https://www.passivebuildings.ca/post/largest-passive-house-retrofit-in-canada