Steam Lines and Condensate Return Instructions
The following instructions must be followed for installation of steam lines for the HM700. Failure to use recommended
material and exceeding maximum recommended length in Table 4, or failure to follow any other steam line installation
instructions will result in improper operation and could void the warranty.
Table 1. Recommended Steam Line Material for HM700 Duct.
*
The use of steam line other than copper, stainless steel tube or Honeywell supplied steam line will void the warranty
and may adversely affect the operation of the humidifier.
*
When using copper or stainless steel tubing (other than the supplied tubing), insulation is recommended due to high
temperature safety as well as reduced condensate.
CAUTION
Plumbing to be performed by licensed HVAC
professionals only.
Drain water from humidifier can be very hot. Do
not drain to public sink.
All plumbing work should be done according to
local plumbing code.
CAUTION
Installation
Do not mount in area where freezing can occur.
Do not mount on floor.
Humidifiers produce steam at atmospheric
pressure. No devices which could block steam
output should be connected to the steam outlet.
Steam lines must be installed so that no restriction
can produce backpressure in the humidifier.
Regardless of selecting on/off or modulating
control method, Honeywell humidifiers must
have a closed circuit across its on/off security
loop control terminal to operate. Honeywell
highly recommends the use of a duct high limit
humidistat.
Steam Line Installation
1.
Honeywell steam hose should only be used on
short steam runs (under 15 feet).
2.
Ensure that no condensate produced in the steam
line will remain trapped. Steam naturally flows
upward and condensate naturally flows downward.
3.
Ensure steam line properly supported so that no
sags or dips are present.
4.
All bends should be done in large radius 12 in.
minimum. Steam hose will soften when and may
kick if too tight a radius is used which can cause a
blockage and excessive back pressure.
5.
Horizontal runs of steam must rise 2 in. per foot
(10º) when flow is going upwards away from the
humidifier, or fall 1/2 in. per foot (2º) when flow is
going downwards away from the humidifier.
Condensate Return Guidelines For Main
Steam Lines
1.
Use vertical condensate leg of distributor only. Do
not over-tighten clamp.
2.
Condensate traps on steam mains must be located
at all low points in the system, at each elevation
change and or directional change.
3.
Horizontal runs of steam must rise 2 in. per foot
(10º) when flow is going upwards away from con-
densate trap, and fall 1/2 in. per foot (2º) when flow
is going downwards towards a condensate trap.
4.
In a horizontal run of the steam main, condensate
traps must be located at regular intervals.
5.
The condensate trap itself is a section of piping con-
nected to the bottom of the main. A full size tee
must be used to create a condensate trap to allow
the condensate to fall away from the steam flow.
6.
Vertical drop of the condensate trap should be
1.5 times the diameter of the steam main but no
less than 12 in.
7.
A p-trap should be installed at the bottom of the
condensate trap. The center to center trap height
should be 2 in. greater than duct static pressure
(see Figure 1).
To return condensate for HM700, insert copper tube
(supplied with equipment) half way into the condensate
opening of the fill cup along with the spring clamp
(supplied with equipment).
Insert the condensate hose into the condensate return
hole at the top of the unit, and over the copper tube.
Fasten in place with the spring clamp.
Voltage
Steam Output
Material
*
Maximum
Steam Line
Length
Possible Losses
Minimum
Airflow CFM
Max Static
Pressure
lbs/hr
(kg/hr)
Steam
Hose
MED-L
Copper
Tube
Stainless
Steel Tube
ft
(m)
lbs/hr
(kg/hr)
110/120V
3.85
(1.75)
7/8 in.
3/4 in.
0.875 x
0.049W
7
(2)
0.5
(0.2)
115
3.0 in. w.c.
220/240V
7.7
(3.5)
12
(3.5)
1.5
(0.7)
230
