Steam Line Instructions
The following instructions must be followed for installation of steam lines for the HM750. Failure to use recommended
material (see Table 5), or failure to follow any other steam line installation instructions will result in improper operation
and could void the warranty.
Steam Output Material
lbs/hr
Voltage
(kg/hr) GPD
3.8
110/120V
(1.7)
7.7
220/240V
(3.5)
* The use of steam line other than Honeywell supplied steam hose line will void the warranty and may adversely affect the
operation of the humidifier.
NOTE: Condensate is not returned to the humidifier using a separate condensate line. Rather, the condensate is
returned to the humidifier via the steam line. Ensure proper sloping.
If a condensate pump is preferred, ensure the pump is rated for hot water.
Main Rules for Atmospheric Steam Lines
• Steam lines must not have any restrictions which could
result in back pressure.
• Maximum recommended steam line length: 15 ft. (4.6 m)
• Use only Honeywell supplied hose and follow
recommended lengths.
• Install steam line in a vertical (upwards) fashion from
the HM750 to the distribution nozzle, with a minimum
slope of 4 in. (10 cm) RISE for every 12 in. (30 cm) RUN.
• Insulate with 1.5 in. (3.8 cm) pipe insulation on steam
hose (recommended).
• Do not over tighten hose clamp at cylinder steam outlet.
• If the 15 ft. steam hose is used, support the hose to
maintain proper slope and avoid excess weight on the
humidifier and nozzle.
Steam Distributor Nozzle
Remote-Mount — The HM750 must be connected with a
steam hose to a steam distributor nozzle installed in the
supply-side of ductwork. As shipped, the HM750 is
configured with a steam guide for remote mounting. The
steam outlet points upwards and is only used when the
humidifier is installed remote to the air supply duct.
The steam distributor nozzle should be installed as close
as possible to the humidifier – to a maximum of 15 ft.
(4.6 m). The HM750 is supplied with a 5 ft steam hose. A
15 ft hose is available as an accessory. Short steam
distribution lines minimize condensate loss and the
possibility of generating backpressure in the steam
distribution line. It is important that the steam line have a
constant slope of, as a minimum, 4 in. (10 cm) RISE for
every 12 in. (30cm) of RUN. See Fig. 8.
Table 5. Recommended Steam Line Material for HM750 Duct.
*
Steam
Hose
Recommended:
11
1 in. dia.
22
15 ft. (4.6 m)
Possible Losses Minimum
Steam Line
Length
lbs/hr
0.4
5 ft. (1.5 m)
Maximum:
0.4
Fig. 7. Molded steam guide.
4
(105)
12 (305)
Fig. 8. Minimum slope requirements for steam line.
Measurements in inches (mm).
7
HM750A1000
Max
Airflow
Static
GPD
CFM
Pressure
1.1
115
2.0 in. w.c.
1.1
230
AIR SUPPLY DUCT
STEAM DISTRIBUTOR
NOZZLE
STEAM HOSE
HUMIDIFIER
MOLDED
HOSE
GUIDE
HOSE
CLAMPS
STEAM
HOSE
STEAM
CYLINDER
M37216
33-00289EF—02