GeneralAire GFDS25LCBU Steam Humidifier | Installation in Montreal, Laval, Longueuil, South Shore and North Shore
Is it the right size for your home?
It produces 35 gallons of steam a day (at 230 V, 12 lb/h), enough to humidify about 4,200 sq ft (our estimate). Pick your home's living area.
It's the right size.
For a 2,500 to 3,200 sq ft house, it's within its range. It will run at part load on ordinary days and keep a reserve for the coldest days.
AirGreen estimate. GeneralAire advertises 'up to 6,000 sq ft' for the DS25 without saying how tight the house is. For an average-construction home, we count 120 sq ft per gallon a day, the ratio in AprilAire's and Lennox's tables. Older or leaky house: go one size up; our estimator confirms it on site.
What it does, in numbers
$113
Electricity per winter
It rarely runs at full output
Same period for every line, November 1 to March 31 (150 days), at Hydro-Québec's Rate D second tier (11.142 ¢/kWh). At full output it costs $0.43 an hour.
Full output with a heat pump. It heats its own water, so it doesn't depend on the air temperature in the ducts.
Output and current: manufacturer's spec (35 gal/day, at 230 V, 12 lb/h), hence 3.9 kW. Cost per winter: 2,000 sq ft house with 9 ft ceilings, 0.35 air changes per hour (the same basis as our air exchangers), −5 °C and 75% humidity outside on average, 35% targeted indoors, minus the moisture a family of four already produces. A leakier house, or a higher setting, costs more.
What you should know about this one
Published, verifiable figures, not brochure claims.
35 galWhat it produces per day, at full output
About 132 litres of water turned into steam in 24 hours. The control runs it to match the humidity you set: it rarely runs flat out, except in very cold weather.
SteamIt doesn't depend on warm air
An evaporative humidifier needs warm air to evaporate the water from its pad. Behind a heat pump, which blows cooler air than a furnace, it produces less. This one heats its own water: same output, whatever the system.
0No pad to replace every fall
The electrodes and the cylinder wear according to water hardness. We check them at the yearly service, along with the rest of the system.
LCFor very soft water
LC means low conductivity: it's built for water from 125 to 400 µS/cm, with the 35-15 cylinder. For ordinary tap water, it's the GFDS25PBU.
25 to 35 galIts output range
GeneralAire gives 25 to 35 gal/day (9 to 12 lb/h). The figure shown here is the maximum, at 230 V.
BUInstallation kit included
BU is the version shipped with the duct-mount kit: 6 ft steam hose, nozzle, condensate hose, air-proving switch and GFX3 humidistat.
ControlThe control that comes with it
GeneralAire GFX3 automatic digital humidistat, supplied in the installation kit.
UpkeepWhat gets replaced, and when
35-15 low-conductivity cylinder, replace about once a year.
35%The humidity to aim for in winter, at most
At −7 °C, no more than 35%; at −18 °C, no more than 25%. Above that, the moisture condenses on the windows. The control adjusts for you if it has an outdoor sensor.
5 yearsThe manufacturer's warranty, and what it covers
5 years on parts (units sold since 2016). Cylinders and gaskets aren't covered. We register the warranty in your name at start-up.
What it needs on site
A steam humidifier needs an electrical circuit of its own. Our estimator checks the panel, the water supply and the drain before ordering.
Complete spec sheetData and cited sources
- Brand
- GeneralAire
- Model
- GFDS25LCBU
- Type
- Steam humidifier (electrode)
- Output
- 35 US gal/day (at 230 V, 12 lb/h)
- Control included
- GeneralAire GFX3 automatic digital humidistat, supplied in the installation kit.
- Upkeep
- 35-15 low-conductivity cylinder, replace about once a year.
- Living area
- 4,200 sq ft (AirGreen estimate)
- Heat pump compatible
- Yes
- Dimensions (L × D × H)
- 13.13 × 8.25 × 23.75 in
- Power supply
- 230 V
- Current
- 16.95 A
- Power
- 3.9 kW
- Breaker
- 25 A max
- Weight
- 20 lb
- Warranty
- 5 years on parts (units sold since 2016). Cylinders and gaskets aren't covered.
Output, dimensions, electrical data and warranty: GeneralAire manufacturer's data. Living area: AirGreen estimate, explained under « Your home ».
The next model down and up
Talk to an HVAC technician before you choose
We look at your heating system, the electrical panel, the water supply and the drain, and give you an installed price.
GeneralAire GFDS25LCBU: the DS25 version for very soft water
The GFDS25LCBU is a steam humidifier that delivers 35 gal/day at 230 V, or 12 lb/h. It suits a home of about 4,200 sq ft by our estimate. It targets one specific case: water that conducts electricity poorly.
LC: low conductivity
An electrode cylinder heats the water by passing current through it. If the water is very soft, it conducts too little. LC means low conductivity: this model is built for water from 125 to 400 µS/cm, with the 35-15 cylinder. For ordinary tap water, it's the GFDS25PBU. Otherwise the two units are identical, BU kit and GFX3 humidistat included.
What the installation requires
Your water's conductivity is checked before choosing between the two versions. The unit draws 16.95 A on 230 V (3.89 kW), on a 25 A breaker. The duct must supply at least 1,000 CFM, with 36 in. of straight duct ahead of the nozzle. It needs a water supply and a drain. The 35-15 cylinder is replaced about once a year. The 5-year warranty covers parts, not the cylinder or gaskets.
To get a quote
Call AirGreen at 514 316-2973. Our estimator comes to check the heating system, the electrical panel, the water and the drain, then gives you a quote for the installed unit. We work in Montréal, Laval, Longueuil, the South Shore and the North Shore.