Install Instructions

H7625, H7726, H7735, H7736 HUMIDITY/TEMPERATURE SENSORS
3 31-00444M—01
TROUBLESHOOTING
Table 1. Troubleshooting.
CALIBRATION
Honeywell RH sensors are factory calibrated to NIST
traceable standards. No field calibration is necessary or
recommended. However, to facilitate compliance with
commissioning requirements field calibration offsets are
allowed.
1. Locate calibration instrument and sensor in close
proximity to each other in a controlled environment
free of drafts, people, and equipment to reduce influ-
ence on RH and temperature.
2. Allow both readings to stabilize (10-30 minutes).
Compare reading of sensor to calibration instru-
ment, and calculate difference.
3. Refer to OPERATION section to change offsets as
needed. Setting an offset of zero restores factory cal-
ibration.
RECYCLING
Product should not be thrown away in regular trash.
Instead, it should be recycled according to local
municipality.
SPECIFICATIONS
Table 2. Models.
Table 3. Specifications.
1
One side of transformer secondary is connected to signal
common. Dedicated transformer is recommended.
2
Time for reaching 63% of reading at 25oC and 1 m/s air-
flow.
3
Long term exposures to conditions outside normal range
or high humidity may temporarily offset the RH reading
(+3%RH after 60 hours).
4
15-30VDC/24VAC power supply voltage required for 10
volt output.
Symptom Solution
No output
Check wiring. Ensure power supply
meets requirements.
Temp or RH
reading error
Verify control panel software is
configured for correct output scaling.
Verify accuracy of test instrument.
Observe installation and calibration
guidelines.
Verify unit is securely installed on duct
without excessive air leakage.
Offset calibration only if necessary.
Sensor damage,
contamination,
or long-term
drift
Replace sensor element. Consult
factory for ordering information.
Model
Humidity
Accuracy Thermistor Enclosure
H7725B2006 2% 20 kOhm Duct
H7725B2006-C 2% NIST
Certified
20 kOhm Duct
H7726B2024 2% 1097 Ohm Duct
H7735B2018 3% 20 kOhm Duct
H7736B2026 3% 1097 Ohm Duct
H7735C2015 3% 20 kOhm Outdoor
Power supply
AC Supply/
DC Supply
24VAC, 100mA max.
12-30VDC, 50mA max.
Outputs RH
3-wire 0-5V/10V
4
,
3-wire or 2-wire 4-20mA (Selectable)
Output scaling RH 0-100%RH
Thermistor/
RTD
Nominal
resistance @ 25 °C
20 kOhm
1097 kOhm
Media filter
PBT with water vapor-permeable
membrane
Relative
Humidity
Accuracy
2% models: ±2% max 0 to 100% RH,
±1.5% typ 0 to 80% RH @25°C
3% models: ±3% max 0 to 100% RH,
±2% typ 0 to 100% RH @25°C
Resolution 0.01% RH
Hysteresis ±0.8% RH
Repeatability 0.08% RH
Non-linearity Factory linearized <1%RH
Temperature
coefficient
Fully compensated by on-board
sensor
Response time
2
8s
Output update 0.5s
Operating range 0 to 100% RH (non-condensing)
Long term drift <0.25% RH per year
Operating
conditions
3
41 to 140°F
(5 to 60°C)
@ 20-80% RH
Enclosure
Materials ABS/Polycarbonate
Dimensions
4.0”h x 4.4”w x 2.1”d
Duct: (+6.8” probe)
Outdoor: (+2.8” Solar Shield)
Enclosure Rating
Duct: IP20/NEMA 1
Outdoor: IP20/NEMA 1 *Vent bottom
of enclosure to achieve NEMA 3R
Rating
Unit Temp Rating -40°F to 158°F (-40 to 70°C)