Home & Garden

Whole House Steam Humidifier - Worth the money?

  • Last Updated:
  • Oct 30th, 2019 9:21 pm
Jr. Member
Sep 10, 2006
157 posts

Whole House Steam Humidifier - Worth the money?

Searched the forum - there are some discussions on the bypass models but not on the steam humidifier, therefore thinking about starting a new post.
Our 2yr-old house is about 3,400 sq ft (4,300 including the basement). It has 3 floors: main + basement + 2nd using 1 set of HVAC system and the 3rd floor has its own HVAC. We also have a HRV system installed.
With a 1yr old baby, I am thinking about getting a whole-home humidifier installed. Have been comparing the Aprilaire 800 (Steam) and 700A (Bypass) model.
Based on their descriptions, both models should fit the size of our house. However, when getting the quotes, some HVAC companies strongly recommend the steam model and said the bypass model may have trouble getting to 40% during the extreme cold condition.
800 is much more expensive - about $1,000 higher for the initial cost and $80 more for the annual maintenance to change the canister.
Does it really worth to get the 800/steam model? Any advice will be much appreciated.
2 replies
Deal Expert
User avatar
Jun 12, 2007
17895 posts
RH 40% is the max setting if outside temp is above 0C
in extreme cold, the max RH setting becomes 15-20% at -30C


If you run too much RH, you will get a lot of condensation. This will either damage the house or cause mold growth
GTA wise, set for 30-35%
Last edited by l69norm on Oct 31st, 2019 5:20 am, edited 1 time in total.
Deal Addict
Dec 17, 2007
2622 posts
Alliston, ON
You are in a new house, the humidity levels won't drop as much as they do in older more drafty houses. The 800 also requires 240v power, but it can run independently of the HVAC system.
I'd go with the 700, it should be able to more than handle your needs.