GeneralAire GFDS25PBU 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' 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.
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.
Tap waterFor ordinary tap water
The version for water from 400 to 1,250 µS/cm. For very soft water, the GFDS25LCBU takes a matching cylinder.
ControlThe control that comes with it
GeneralAire GFX3 automatic digital humidistat, supplied in the installation kit.
UpkeepWhat gets replaced, and when
35-14 cylinder for normal-conductivity water, 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
- GFDS25PBU
- 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
- 35-14 cylinder for normal-conductivity water, 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 GFDS25PBU: up to 35 gal/day of steam from tap water
The GFDS25PBU is an electrode-cylinder steam humidifier. It delivers 35 gal/day at 230 V, or 12 lb/h. That's enough for a home of about 4,200 sq ft by our estimate. Its steam doesn't depend on the air temperature, an advantage with a heat pump.
The version for ordinary water
- GeneralAire gives a range of 25 to 35 gal/day (9 to 12 lb/h). The figure shown is the maximum, at 230 V.
- Its 35-14 cylinder is built for water from 400 to 1,250 µS/cm, ordinary tap water. For very soft water, it's the GFDS25LCBU.
- The BU includes the duct-mount kit, with the GFX3 digital humidistat.
Power, duct and upkeep
It needs a 230 V circuit and draws 16.95 A, for 3.89 kW, on a 25 A breaker. The duct needs at least 1,000 CFM of air and 36 in. of straight duct ahead of the nozzle. Plan for a water supply and a drain. The 35-14 cylinder is replaced about once a year. The 5-year warranty covers parts, except the cylinder and gaskets.
AirGreen handles the installation
We sell this unit and we install it. An estimator first looks at your heating, your panel, your water supply and your drain, then gives you a quote. Service in Montréal, Laval, Longueuil, the South Shore and the North Shore: 514 316-2973.