13
Installation
Nortec EL
2582302_C_EN_1611
Legend:
1 High limit On/Off humidistat (external safety chain)
2 Humidity sensor or modulating humidistat (used for control of space in return duct, or high limit in supply duct)
3 On/Off humidistat (used for humidity control)
4 Steam line (see Note 1 below)
5 Electrical disconnect, high voltage supply
6 Drain line (see Note 2 below)
7 Air gap with optional trap (see Note 3 below)
8 Water supply (see Note 4 below)
9 Condensate line (see Note 5 below)
10 Steam distributor (see Note 6 below)
11 Air proving switch (external safety chain)
12 Supply air duct
13 Return air duct
Note 1:
The steam line should be as short as possible – the maximum length varies depending on unit
capacity and material used (refer to
Table 6 on page 28
). The steam line should have adequate upslope
(minimum 10°) /downslope (minimum 2°), without restrictions and with a condensate trap at the lowest
point. Steam traps are required every 15 ft (5 m) for long runs. The steam line must rise a minimum of
12 in (30 cm) straight up before running to the steam distributor. The minimum bend radius for steam
hose is 12 in (30 cm), or 5× the internal diameter for rigid pipes. Refer to
Table 6 on page 28
for steam
line recommendations.
Note 2:
The drain line should have a minimum internal diameter of 7/8 in (22 mm), with a constant
minimum downslope of 1 in/48 in (1.2°) to the funnel, and must not touch the sides or bottom of funnel.
Note 3:
The air gap and trap should be located to the left of the humidifier, as shown. A 2-1/2 in to 7/8 in
(63.5 mm to 22 mm) reducer is ideal (Nortec option P/N 2522172). The hose must not touch the bottom
of the funnel.
Note 4:
Water supply should be potable drinking water, with conductivity of 150-1200 micro-siemens/
cm (0-12 gpg). The water supply line should have a minimum diameter of 1/2 in (13 mm) with a shutoff
valve. An optional 5 μm filter is also recommended. Water temperature should be 34-104°F (1-40°C).
Pressure should be surge-free and regulated to 30-80 psig (207-550 kPa).
Note 5:
Condensate drain line from the steam distributor should have a constant minimum downslope
of 1 in/48 in (1.2°), with no restrictions and a minimum trap height of 8 in (200 mm). The trap should be
located a minimum of 12 in (30 cm) below the steam distributor.
Note 6:
The distance from the steam distributor to any obstruction or transition in the duct should be
equal to the calculated absorption distance B
n
or a minimum of 8-10 ft (2.4-3 m) if B
n
is not known. For
details refer to the installation manual for the relevant steam distribution system. The absorption distance
can be obtained using
Nortec HELP
. The steam distributor capacity must equal or exceed the maximum
capacity of the humidifier.