Pure Humidifier EC Series Operation and maintenance manual

TM
READ AND SAVE THESE INSTRUCTIONS
Standard Water
EC Series
Electric Humidifier
Installation Instructions
Operation and Maintenance Manual
Our results are comforting
PURE HUMIDIFIER® and INTAC® are registered trademarks of PURE Humidifier Co.
Form No: ECOM-4-2023

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Introduction
Introduction
Capacity & Electrical Specifications
Dimensions & Layout
Humidifier Layout
Installation & Location
Wall Mounting Detail
Dispersion Methods
Injection Tube & Flexible Hose Kit Installation
Steam Supply Piping Examples
Piping
Blower Pack
Pre-Startup Checklist
Non-INTAC®PLC Startup Procedure
INTAC®PLC Startup Procedure
Maintenance & Cleaning Instructions
Cover Gasket Replacement Instructions
Troubleshooting
Tool Requirements & Torque List
Maintenance Notes
Exploded Parts Drawing
Parts List
1
2
3
4
5
6
7
8
9
10
11
13
14
15
16
17
18
19
20
21
22
To the user of PURE Humidifier Co.’s Electric Humidifiers
We at PURE Humidifier Co. thank you for choosing one of our
quality products. PURE Humidifier Co. Electric Series Humidifiers
are models of simplicity to install, operate, and maintain. However,
they must be maintained to provide maximum operating
efficiency.
PLEASE READ AND FOLLOW ALL INSTRUCTIONS
CAREFULLY. PROPER OPERATION AND HUMIDITY CONTROL
IS POSSIBLE ONLY WITH PROPER INSTALLATION AND
MAINTENANCE.
The EC Series Humidifier utilizes a Tri-Probe Sensor conductive-
type water control system, which is designed for use with standard
(hard or soft) tap water. Use of deionized, demineralized, or reverse
osmosis water will cause a failure of the water level control system
and void the warranty.
High chloride content in feed water can cause chloride stress
cracking and chloride pitting in stainless components. Chloride
stress corrosion cracking (CSCC) and chloride pitting of stainless
steel components is not covered by warranty. Do not use
hydrochloric acid descalers or bleach to clean the tank. We offer an
easy-to-use, non-toxic descaling solution to help keep your units
clean and operating with maximum efficiency. Please contact your
local PURE Humidifier representative for more information about
our PURE Clean descaling solution.
PURE Humidifier Co.’s ECDDR Series should be installed on
applications that require deionized, demineralized, or reverse
osmosis water.
To ensure proper installation of this product, it must be installed
by qualified HVAC and electrical contractors, and must be in
compliance with local, state, federal, and governing codes. If
installed improperly this product may cause damage to property,
severe personal injury, or death as a result of electric shock, burns,
and/or fire.
Do not adjust any components inside humidifier control panel
without consulting the factory.
Installation of humidifier in high humidity or salt water atmospheres
will cause accelerated corrosion, resulting in a reduction of the
normal lifespan of the unit.
For indoor use only.
Table of Contents
The PURE Humidifier Co. Warranty
PURE Humidifier Co. guarantees its products to be free from
defects in material and workmanship for a period of two years from
the date of shipment; provided the product is properly installed,
serviced, and put into the service for which it was intended.
PURE Humidifier Co. is obligated under the terms of this warranty
to the repair or replacement of the defective part(s), excluding any
labor charges, or to refund the purchase price at our option. PURE
Humidifier Co. assumes no obligation for incidental or consequential
damages. The above provisions are in lieu of all other guarantees,
obligations, liabilities or warranties, expressed or implied.
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Capacity, Weights &
Electrical Specifications
* EC-5 at 120/1 requires 3 heating elements.
† The above capacities are based on 100% efficiency. Actual humidifier capacity may vary due to the heat loss from the humidifier
reservoir. The ambient air temperature, air velocity, and injection tube system will affect the rate of heat loss from the humidifier reservoir.
Capacity & Weights
EC Series
Electrical Specification
EC Series
Standard
Water Unit
Model No.
Steam Output Capacity † Humidifer Weight
lbs/hr kg/hr Empty Full
lbs kg lbs kg
EC-5 15.0 6.8 139.0 63.1 223.0 101.2
EC-10 30.0 13.6 140.0 63.5 224.0 101.6
EC-15 45.0 20.4 141.0 64.0 225.0 102.1
EC-20 60.0 27.2 142.0 64.4 226.0 102.5
EC-25 75.0 34.0 143.0 64.9 227.0 103.0
EC-35 102.0 46.3 146.0 66.2 230.0 104.3
Standard
Water Unit
Model No.
KW
Single Phase Amperage Three Phase Amperage CONTROL
CIRCUIT
VOLTAGE
No. of
Heaters 120V 208V 240V 480V 600V
No. of
Heaters 208V 240V 480V 600V
EC-5 5 Single 41.7* 24.0 20.8 10.4 8.3 Triple 13.9 12.0 6.0 4.8 24 vac
EC-10 10 Double 41.7 20.8 16.7 Triple 27.8 24.1 12.0 9.6 24 vac
EC-15 15 Triple 31.3 25.0 Triple 41.7 36.1 18.1 14.4 24 vac
EC-20 20 Triple 41.7 33.3 Triple 24.1 19.2 24 vac
EC-25 25 Triple 41.7 Triple 30.1 24.1 24 vac
EC-35 34 Triple Triple 40.9 32.7 24 vac
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Dimensions & Layout
*Removable access plate allows reservoir to slide out
for inspection and cleaning without disconnecting the
steam supply piping.
**See local codes for minimum clearance to
electrical compartment. The electrical access
door requires a minimum clearance of 16” to fully
open.
Key Locked Electrical
Access Door**
Removable
Access Plate*
Removable Key Locked
Reservoir Access Door Touchscreen/
Operation Status
Indicating Lights
Key Locked
Electrical Access
Door
FRONT VIEW
RIGHT SIDE VIEW
BOTTOM VIEW
Note: Dimensions are typical for all EC models.
R
Rem
o
v
ab
l
e
A
A
A
Acc
ess
Pl
a
t
e*
TOP VIEW
17.00”
(43.2)
7.75”
(19.7)
2 3/8” Steam
Outlet Access
14.75”
(37.5)
16”
(40.6)
29.50”
(74.9)
24”
(60.9)
6.50”
(16.5) 2.375”
(6.0)
Reservoir Drain Outlet
1 7/8ӯ
15.00”
(38.1)
8.4375”
(21.4)
2.00”
(5.1)
1.50”
(3.8)
Electrical Inlet 1 1/8ӯ
Water Inlet 3/8” NPT
Cabinet Overflow
1/2” NPT
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Humidifier Layout
Humidifier Features
• SCR modulating control
• Electronic water level control system
• Accumulative automatic timed drain system
• Seasonal end-of-use drain system
• High efficiency incoloy immersion water heaters
• 18-gauge steel cabinet with baked enamel paint finish
• Internal stainless steel evaporating reservoir mounted
on slides for easy removal
• Key locked doors for both reservoir and electrical
access
• Easy and simple installation options
• Dispersion methods include Insty-Pac*, Fast-Pac,
Injection Tube*, or Blower Pack assembly* for room
distribution
• Manual reset over-temperature safety switch
• INTAC®PLC control system
• VAV dual modulating control system*
* Optional features
Touchscreen/
Operating Status
Indicating Lights
Steam Outlet
Connection
Over-Temperature
Switch
Removable
Humidifier
Cover
Removable
Humidifier
Reservoir
Immersion
Heaters
Tri-Probe
Sensor
1/4”-IPS Water
Inlet & Strainer
Removable Key Locked
Reservoir Access Door
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Installation & Location
Important: Remove all shipping brackets and materials
before operating the humidi¿er. Humidi¿er Àue gases
must be vented to the outside atmosphere. Power
supply disconnect switch must be in the oႇposition while
making wiring connections to prevent electrical shock
and equipment damage. All units must be wired in strict
accordance with wiring diagram furnished with this unit.
Turn oႇall gas while installing the supply gas piping and
¿eld installed manual gas shut-oႇvalve for the humidi¿er.
Location
The location selected must provide for electrical service,
cold or hot water supply, and sanitary drain.
When selecting a location, try to keep the humidi¿er within
10 feet (305 cm) of the duct to avoid unnecessary heat
losses and condensation within the steam supply line.
Visible “fog” will saturate and condense when it contacts
objects such as turning vanes, ¿lters, fans, elbows or take-
oႇs. The warmer the air, the more easily it will dissipate
the visible steam. The most active and warmest portion of
the duct will provide better mixing of the steam and air. The
injection tube should be mounted a minimum of 2 feet (61
cm) downstream from an elbow or other turbulent air Àow
area.
Avoid mounting single style injection tube(s) closer than
8-10 feet (244-305 cm) upstream of objects that could
become saturated and condense the steam (reference
the paragraph above). If the duct layout does not provide
a straight unobstructed run of 8-10 feet (244-305 cm), a
multiple injection tube system should be considered to
reduce the visible steam travel distance.
For Fast-Pac and Insty-Pac multiple tube assemblies
please consult factory for job speci¿c non-wetting
distances.
Reference Fast-Pac or Insty-Pac O&Ms for full installation
details.
CAUTION: Do not humidify upstream of ¿lters. Consult
factory.
CAUTION: Smoke detectors should not be located
downstream of injection tube assemblies.
Location of Controls
It is important to avoid mounting any controls within the
visible steam. The controls should be mounted a minimum
of 8-10 feet (244-305 cm) downstream from the humidi¿er
injection tube. Due to the temperature rise that exists
within the visible steam dissipation area, thermostats
should not be mounted near the injection tube.
High-limit humidistats should be installed before any duct
obstruction to make sure the humidi¿er is interrupted
before saturation can occur on the object. The high-limit
should be mounted a minimum of 8-10 feet (244-305 cm)
downstream from the injection tube. Installing the high-limit
closer than 8 feet (244 cm) from the humidi¿er may cause
erratic control.
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Mounting
The humidifier should be mounted dead level in both directions. PURE Humidifier Co. supplies a wall mounting bracket.
Bracket is mounted to wall studs first. The bracket must be mounted to wall studs or additional support must be provided in
the field. EC cabinet is then hung on slip-fit bracket.
Wall Mounting Detail
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Injection Tube and Flexible Hose Kit
Allows remote mounting of the humidifier reservoir
from the duct. Also allows the humidifier to be located
below a wall-mounted duct. See page 8 for details.
Dispersion Methods
Insty-Pac and Fast-Pac
Multiple Injection Tube Assemblies
For applications where you need a short dissipation
distance. Allows remote mounting of the humidifier
reservoir from the duct. Also allows the humidifier to
be located below a wall-mounted duct. See page 9
for details.
Blower Pack for Direct Room Humidification
Allows humidifier to be mounted directly on the wall
within the space to be humidified. See page 11 and
12 for details.
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Flexible Hose Kit Installation
Hose kits should have the injection tube installed
in the center of the duct. Hose and injection tube
should be pitched back to the humidifier two
inches (5 cm) per foot (31 cm). If proper pitch
cannot be maintained, or the injection tube is
mounted lower than the humidifier, a drain “tee”
will be required (reference drain “tee” illustration).
Install the tube with the steam ports injecting
steam up. NOTE: If narrow ducts (6”/15 cm or
less, in height) are utilized, install the tube with
the steam ports injecting slightly with the air flow
(2 o’clock position).
The hose connects to the injection tube and
humidifier with stainless steel hose clamps (by
PURE Humidifier Co.).
Galvanized steel duct plates are provided to seal
the opening where the tube enters the duct.
Injection Tube & Flexible Hose
Installation
The water seal height may have to
be increased if excessive duct static
pressure exists.
Δ
Typical EC Series
Electric Humidifier
3/4” SW Condensate
Drain Line (by others)
Stainless Steel
Drain Tee
(optional)
Duct (beneath
humidifier)
Open Sanitary
Drain
“H”
Water
Seal
Height
Total KW
5 thru 20
21 thru 34
“H”
6” (15 cm)
8” (20 cm)
Water Seal Height Δ
Flexible Hose
Typical EC Series
Electric Humidifier
Flexible Hose
Pitch 2” (5 cm) per foor (31 cm)
back to the humidifier.
Duct Plate
Duct
Injection Tube
Pitch 2” (5 cm) per foor (31 cm)
back towards the humidifier.
8”
4” Insertion Length/
Duct Width
1 1/2” Ø
Tube Detail
8

Pitched Towards Steam Generator
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Steam Supply Piping Examples
Notes:
1. Pitch hard piping or Àexible hose 2” per foot if steam is Àowing uphill, ¹»๞” per foot if the steam is Àowing
downhill. Reference piping examples shown.
2. When feasible to do so, install a minimum one-foot riser from the top of the tank to reduce condensate carryover.
3. Use Àex connectors or unions to allow for easy removal of cover.
4. Support Àexible hose every 18” to avoid sagging.
5. Hard piping or Àexible hose must match reservoir outlet size. Do not use supply piping with a smaller inside diameter
than the reservoir outlet.
6. Failure to follow the piping recommendation on this page may result in blown water seals, leaking cover gasket, or
dispersion tubes spitting.
7. Install a Drain Tee at any low spots in supply piping run where condensate will accumulate. All horizontal to vertical
up transitions require a water-sealed drip leg.
8. Reference job speci¿c tube assembly O&M included with your order for complete details.
Pitched Towards Tube Assembly
Pitched Towards Steam Generator
and Tube Assembly
Pitched Towards Drain Tee
Pitch
(see Note 1)
Use two 45° elbows for
hard piping or wide 90°
for Àexible steam hose
Supply piping
connectors
(see Note 4)
Drain Tee
(see Note 7)
Typical
Humidi¿er
Reservoir
see Note 2
see Note 2
see Note 2 see Note 2
2”/1’
2”/1’ 2”/1’
¹»๞”/1’
¹»๞”/1’
¹»๞”/1’
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Piping
Water Supply Piping
This style of humidifier utilizes a Tri-Probe conductive
type water control system which is designed for use with
standard (hard or softened) tap water. Use of demineralized,
deionized or reverse osmosis water will cause failure of the
water level control system and void the humidifier warranty.
Cold or hot standard tap water can be supplied to the
humidifier. A minimum water pressure of 35 p.s.i. (2.4 Bar)
should be maintained to provide the proper water level within
the humidifier. DO NOT exceed the maximum acceptable
water pressure of 95 psi (6.6 Bar). If the water pressure is
above 95 psi (6.6 Bar) a pressure reducing valve should be
installed. Failure to do so will cause the supply water hose to
burst due to excessive heat and pressure.
The humidifier has a factory built-in 1.5” (4 cm) air gap
between the water inlet and the overflow. Local codes should
be checked to see if the addition of a vacuum-breaking
device is required. Water connection is made at the bottom
of the humidifier with 3/8” NPT piping.
Drain Piping
The EC style humidifier requires two copper drain piping
connections run to an open drain.
The drain piping should be copper or stainless steel. The
use of PVC piping is not recommended; the humidifier water
temperature may cause the PVC to soften and fail. Use a
drain tempering kit before transition to PVC.
The EC humidifier has a factory-piped internal water seal/
overflow. The water seal must be filled (primed) prior to
operation. Remove the Tri-Probe sensor from the tank until
the water overflows into and primes the water seal. Once
this is done replace the Tri-Probe sensor.
If gravity drain is not possible please use a condensate
pump rated for 212°F water or contact a PURE Humidifier
Co. representative to purchase one.
Open Sanitary
Drain
3/8” NPT Water Inlet
Cabinet Overflow
Drain
3/4” Drain
Typical EC Series
Humidifier (Right
Side View)
WARNING:
Humidifier Reservoir Drain and Cabinet Overflow
Drain (see page 3) MUST be run separately.
These lines CANNOT be tied together into a
common drain line. Draining malfunction will occur
causing damage to the humidifier system.
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Optional Blower Pack
In applications where a ducted air system is not available,
PURE offers the optional Blower Pack. The Blower Pack
contains a two-speed adjustable blower that moves the air
over the steam discharge outlet and disperses the steam
directly into the space (see Fig. 1). The Blower Pack mounts
directly on top of the EC humidifier or can be remote mounted
(see Fig. 2).
Blower Pack
Locating Blower Pack
The distance that visible steam will travel after leaving the
Blower Pack is dependent upon the relative humidity in
the room and the capacity of the humidifier. If this visible
steam comes in contact with any solid object (walls, beams,
machinery, etc.), it may form condensate and drip. Refer to
Fig. 3 and Table 4 (Table 4 is located on page 12) for data on
visible steam travel. This will aid you in planning the location
of the Blower Pack.
Remote Mounting
The Blower Pack may be remote-mounted up to ten feet
away from the EC wall mount humidifier (see Fig. 2).
Blower Pack Air is drawn into
the Blower Pack
Steam is discharged
directly into space
EC Wall Mount Humidifier
Remote Blower Pack
6” Water Seal
EC Humidifier
Throw
Rise
EC w/Optional Blower Pack
Fig. 1
Visible Rise and Throw
Fig. 3
Remote-Mounted Blower Pack
Fig. 2
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Locating Blower Pack
The distance that visible steam will travel after leaving the Blower Pack is dependent upon the relative humidity in the room
and the capacity of the humidifier. If this visible steam comes in contact with any solid object (walls, beams, machinery, etc.)
it may form condensate and drip. Refer to Fig. 3 (Fig. 3 is located on page 11) and Table 4 for data on visible steam travel.
This will aid you in planning the location of the Blower Pack.
Blower Pack
Visible Steam
Rise & Throw
Humidifier Model
EC-5 EC-10 EC-15 EC-20 EC-25 EC-35
50%
RH
Rise (ft) 1’ 2’ 3’ 4’ 5.5’ 8’
Throw (ft) 8’ 10’ 13’ 16’ 18’ 23’
60%
RH
Rise (ft) 2’ 3’ 4’ 5’ 6’ 8’
Throw (ft) 13’ 14’ 16’ 18’ 20’ 25’
Throw is the horizontal distance the visible steam travels from the steam discharge.
Rise is the vertical distance the visible steam travels from the steam discharge.
Objects in the direct line of the visible steam or objects that are cooler than the ambient
temperature may accumulate condensation.
NOTE: Data above based on 70°F room temperature.
Optional Blower Pack Dimensions
Fig. 5
Blower Pack weight is 60 lbs (27.2 kg)
* Blower requires a separate 120/1 circuit (by others)
296/435 CFM Fan
120/1/60*, 2.17 amps
1/15 HP
7.75”
(19.6)
17”
(43.18)
29.50”
(74.93)
15”
(38.1)
14.75”
(37.47)
Steam
Discharge
1/4” NPT Drain Connection
Steam Inlet
Front ViewLeft Side View
Table 4
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EC Pre-Startup Procedure
Pre-Startup Checklist
Before starting the EC PURE Humidifier Co. Electric
Humidifier, check the following installation items:
_____ 1. MOUNTING - Verify that the humidifier
evaporating chamber is securely supported and that the
evaporating chamber is level in both directions. If humidifier
is installed above equipment or not located near a floor drain
than a drain pan should be installed below the humidifier
steam generator.
_____ 2. INJECTION TUBE - Verify that the humidifier
injection tube is mounted within the duct with the proper pitch
back to the humidifier (2”/5 cm per foot / 31 cm). NOTE:
If the humidifier evaporating chamber or the flexible hose
(optional) is mounted higher than the injection tube, a drain
“tee” is required to drain the condensate out of the injection
tube steam line. If it is an Insty-Pac or Fast Pac refer to the
respective O&M to determine if they are mounted properly
and have the proper p-trap size.
_____ 3. ELECTRICAL - Verify that all wiring connections
have been connected in accordance with the wiring diagram.
CAUTION: Live power may exist in the control cabinet.
Turn offthe main power at the disconnect switch before
verifying the electrical connections!
_____ 4. SAFETY CONTROLS – The supply air duct RH
high-limit should be installed at least 10 feet downstream
from the humidifier tube(s). Any other control sensors should
be at least 10 feet downstream from the humidifier tube(s).
Smoke detectors should not be installed downstream of the
humidifier tube(s). If a smoke detector absolutely has to
be installed downstream from the humidifier tubes then it
should be installed as far from the tubes as possible.
_____ 5. PIPING: Water Supply - Verify that all piping
connections have been completed as recommended and
that water pressure is available to the humidifier. Verify that
the supply water pressure is 35-95 psi. There should be at
least 5 feet of metal pipe and check valve between the tank
and any plastic pipe.
_____ 6. PIPING: Drain - Make sure a water seal of the
proper height (refer to steam generator O&M for height) is
provided in the drain line.
_____ 7. PIPING: Steam Outlet - Refer to attachment for
proper outlet steam piping from the generator to the tube(s).
Any horizontal to vertical up transition in the outlet
steam pipe requires a water-sealed drip leg! Improper
outlet steam piping will cause steam to leak from the steam
generator. Runs over 20 feet long may require upsizing of
the steam pipe.
Signature:_______________________ Date:_________
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Non-INTAC®PLC Startup Procedure
Start-Up Procedure
_____ 1. With the power “off”, set the switch on the control
board to the “Stand-by” position (the control board
is located within the humidifier control panel door).
_____ 2. Make sure the manual drain valve lever (located
on the front of the drain valve) is in the “automatic”
position.
_____ 3. Turn the controlling humidistat to the lowest
setting (no call for humidity).
_____ 4. Turn the electric power “on” to the humidifier.
The “Power” LED light on the controller should be
illuminated.
_____ 5. Set the switch on the control board to the
“Normal” position.
_____ 6. Open the water supply on/offcontrol valve (by
others) and allow the humidifier evaporating
chamber to fill to the proper level.
_____ 7. After the humidifier is full of water, the “Water
Level Full” LED will illuminate. Turn the humidistat
up to call for humidifier demand.
_____ 8. Make sure all the optional safety switches are
satisfied (airflow proving switch, high-limit
humidistat, etc).
_____ 9. The heater(s) should energize on a call from the
humidistat.
_____ 10. Verify the low water safety circuit by closing the
water supply and opening the manual drain
lever on the drain valve. As the humidifier tank is
draining, the “Water Level Full” and “Heater
Energized” lights should go out and you should
hear the contactor drop out when the low water
level is reached; this indicates the low water
safety circuit is operational. This should only take a
couple of minutes maximum.
_____ 11. Close the drain valve and allow the humidifier
to fill to the proper level.
_____ 12. Check operation of optional field-installed
safety switches (airflow proving switch, high-limit
humidistat, etc.) to make sure that they turn the
power offto the control circuit power. The safety
switches should shut offthe humidifier heaters
whenever one or more of the optional safety
switches create an “open circuit”.
_____ 13. Check heater amperage draw by testing and
recording voltage and amperage in each phase.
Readings should match the factory heater
nameplate.
Amps A:_______ Amps B:______ Amps C:______
_____ 14. Inspect installation for leaks by operating
humidifier at a full rolling boi. This may take up to
15 minutes from a cold start. Any leaks should
be sealed. Just tightening a pressure clamp
will not work if the gasket is not properly positioned
between the sealing surfaces. If necessary, remove
the cover, reseat gasket, and replace the cover.
A small amount of adhesive (super glue,
gorilla glue, spray adjesive, etc) to hold the gasket
in place while repositioning the cover will aid in this
process.
_____ 15. After the unit is producing steam, check and
retighten all hose clamp connections in the system
and make sure they are torqued to 35-40 in-lbs.
There are 6 clamps total inside the cabinet.
Signature:_______________________ Date:_________
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INTAC®PLC Startup Procedure
Startup Procedure
_____ 1. Turn the electric power “on” to the humidifier.
_____ 2. RH Setpoint on the touchscreen should be set to
0.0% RH (no call for humidity). If there is no display
of actual humidity on the touchscreen the procedure
must be done through the Building Management
System.
_____ 3. Open the water supply on/offcontrol valve (by
others) and allow the humidifier evaporating
chamber to fill to the proper level.
_____ 4. Make sure all the optional safety switches are
satisfied (airflow proving switch, high-limit
humidistat, etc).
_____ 5. After the humidifier is full of water the touch screen
will read “Water Level FULL”.
_____ 6. Verify the low water safety circuit by closing the
water supply and opening the manual drain lever on
the drain valve. As the humidifier tank is draining,
the “Filling” status message on the touchscreen will
be displayed. The humidifier should drain to a level
where the touch screen will read “Water Level Low”;
this indicates that the low water safety circuit is
operational. Verify that the Pilot Relay and Contactor
both de-energized.
_____ 7. Close the drain valve and allow the humidifier to
fill to the proper level.
_____ 8. The RH Setpoint on the touchscreen should be
set above the actual reading to get a call for humidity.
If a Building Automation System is controlling the
humidifier, set it to call for 100% demand. For
Building Automation System verify 0% and 100%
demands are displayed as 0% and 100% on the
touchscreen or adjust the input high and low values
to match accordingly.
_____ 9. The heater(s) should energize.
_____ 10. Check operation of optional field-installed safety
switches (airflow proving switch, high-limit
humidistat, etc) to make sure that they turn the
power offto the control circuit power. The safety
switches should shut offthe humidifier heaters
whenever one or more of the optional safety
switches create an “open circuit”.
_____ 11. Check heater amperage draw by testing and
recording voltage and amperage in each phase.
Readings should match the factory heater
nameplate.
Amps A:_______ Amps B:______ Amps C:______
_____ 12. Inspect installation for leaks by operating
humidifier at a full rolling boil. This may take up to
50 minutes from a cold start. Any leaks should be
sealed. Just tightening a pressure clamp will not
work if the gasket is not properly positioned between
the sealing surfaces. If necessary, remove the cover,
reseat gasket and replace the cover.
_____ 13. After the unit is producing steam, check and
retighten all hose clamp connections in the system
and make sure they are torqued to 35-40 in-lbs.
There are 6 clamps total inside the cabinet.
_____ 14. Adjust the RH setpoint back to the desired value.
Signature:_______________________ Date:_________
15

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PURE Humidifier Co. EC Maintenance Instructions
The EC Series Electric Humidifier is designed to provide the best possible operation with minimum maintenance. However,
the humidifier should be inspected and place on a dedicated maintenance schedule to ensure continued operation of the
humidifier and its accessories. PURE Humidifier Co. recommends that the following items be inspected, and/or,
cleaned on a minimum basis of twice a year. If excessive mineral build-up occurs, the maintenance schedule should be
increased.
Maintenance & Cleaning Instructions
Inspect/Maintenance Item
Water Fill Valve
Safety Interlocks
(air flow, high-limit)
Immersion Heaters
Humidifier Cover/Tank
Tri-Probe Sensor
Drain Valve & Drain Piping
Flexible Hose
Procedure to Follow
Check to make sure the fill valve is operating properly. If the valve appears
to continually fill, check the valve seat and seal (see trouble shooting
instructions).
Check to make sure the safety interlocks (air flow, high-limit, etc) will shut
down the humidifier.
Verify the correct amperage is being drawn by the heating element. Reference
the wiring diagram for correct amperage.
Inspect for any leaks. Repair as required. Remove the mineral deposits from
floor of the humidifier reservoir. If excessive build-up is found, the cover may
need to be removed to facilitate complete cleaning of the humidifier.
Remove Tri-Probe Sensor from humidifier (set-screw and o-ring seal) and
inspect for excessive mineral build-up. Inspect plastic housing for cracks.
Probe ends should be cleaned and the probe assembly re-installed.
The drain valve seat and seal should be inspected and cleaned as required.
The drain line and water seal should be inspected and cleaned to ensure free
flow of the overflow and drain line.
Inspect for cracks or leaks. It is normal for the hose to become hard and
develop a “set”.
Cleaning Instructions
Hard Make-up Water
If utilizing hard make-up water, humidifier tanks will likely need to be cleaned manually. This can be done from the side-
entry plate or cover. Remove all loose solids from tank and/or exchanger with a wet vacuum or putty knife and bucket. After
removal of solids, replace the side-entry plate/cover. At this point you may wish to add a descaling solution. Contact your
local representative for our easy to use, non-toxic PURE Clean descaling solution.
Softened Make-up Water
If utilizing softened make-up water, help eliminate build-up in the tank simply by adding a descaling solution. Contact your
local representative for our easy to use, non-toxic PURE Clean descaling solution.
DO NOT use Hydrochloric acid-based descalers; this will corrode stainless steel.
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Cover Gasket Replacement Instructions
Remove the reservoir cover. While looking at the top of the unit, reference Figure A and B to determine which humidi¿er
tank style you have.
Figure A Installation
Fit the gasket around the entire lip of the tank opening. Cut the gasket ¹»๢” longer than required, this will ensure proper
¿t when the cover is clamped back on. Slide the gasket onto lip of tank around the entire perimeter, and seal the ends
together with a small amount of silicone.
Figure B Installation
Fit the gasket around the entire lip of the tank opening. Cut the gasket ¹»๢” longer than required, this will ensure proper ¿t
when the cover is clamped back on. Slide the gasket onto lip of tank around the entire perimeter. Notch only the bottom
Àap of the gasket (reference Fig. C) in the corners of the tank. Seal the ends together with a small amount of silicone.
Fig. A
Plan View of Humidi¿er
Fig. B
Plan View of Humidi¿er
Gasket Top
DO NOT NOTCH
Gasket Bottom
NOTCH HERE
Bottom View of Gasket
Section View of Gasket
Notch gasket Bottom Only
Fig. C
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TM
Problem
Humidifier will not heat
Humidifier will not fill
Humidifier will not stop
filling or is short cycling
Troubleshooting
Possible Cause
Blown heater fuse(s)
Control transformer not
producing 24 vac control
voltage
Safety controls open (air flow
switch, high-limit, etc.)
Over-temp switch
Faulty humidity sensor
Faulty immersion heater
No water pressure
Drain valve open
No power to the fill valve
Fill valve stuck open
Drain valve open
Probes need cleaning
Check probe wiring
Line noise or radio frequency
Recommended Action
Check and replace.
Check transformer output.
Verify voltage across terminals #9 (hot) and #10 (comm).
Verify that all safety controls are completing the safety
circuit.
The level control circuit has interference or is damaged.
Tri-probe Sensor wires should be run separate from
power wiring. Do not reset the switch until the source of
the problem is identified and corrected. Consult factory
if you are unsure of the source of the problem.
Verify voltage to and from humidity sensor.
Check and verify heater voltage and amperage.
Compare to diagram or nameplate label ratings.
Check water supply.
If auto drain system is utilized, verify that the manual
drain lever on the front of the drain valve is closed.
Check for 24 vac across solenoid valve.
Check for 24 vac across solenoid valve. If no voltage,
check for dirt under valve seat.
Close drain ball valve.
If auto drain system is utilized, verify that the manual
drain lever on the front of the drain valve is closed.
Remove Tri-Probe Sensor and clean probe ends.
Grey wire to probe #1 (shortest probe)
Violet wire to probe #2 (middle probe)
Blue wire to probe #3 (longest probe)
Shielded cable may be necessary.
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Tool Requirements & Torque List
Recommended Maintenance Tool List
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