Chemtrol 250 User manual

CHEMTROL 250 ORP/pH Digital Controller
CH250 ORP/pH
DIGITAL CONTROLLER
Installation Operation Bid Specs Brochure
CHEMTROL 250
ORP/pH Digital CONTROLLER
A simple and inexpensive controller for:
●Residential Pools and Spas
●Commercial Pools and Spas
❍Hotels, Motels
❍Health Clubs
❍Apartments Buildings
❍Condo Associations.
●Industrial Water Treatment.
SANITIZER AND pH CONTROL MADE EASY
The CHEMTROL®250 is a microprocessor-based digital controller designed to maintain both sanitizer
ORP (oxidation-reduction potential or Redox) and water pH in high-end residential pools, small
commercial pools and spas and light industrial applications.
Designed for affordability, simplicity of installation, ease of use and long-term reliability, it includes
features normally not found on this type of controller, such as:
• adjustable setpoints,
• adjustable high and low alarms,
• adjustable overfeed safety timers and
• adjustable proportional feed control.
FEATURES
●Easy to install
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CHEMTROL 250 ORP/pH Digital Controller
●Simple to use
●All Control Functions on Front Panel
●Separate Adjustable Setpoints
●Separate Adjustable Alarms
●Acid/Base Selector
●Proportional Feed with Adjustable Bandwidth
●Separate Adjustable Overfeed Safety Timers
●Waterproof Cabinet with Clear Window Cover
●5-year Electronics Warranty
●Toll-Free Technical Support
A SOUND INVESTMENT
The CHEMTROL®250 controller is based on 20+ years of experience in pool and spa automation with
over 25,000 installations worldwide. Featuring a 5-year electronics warranty, it actually pays for itself in
1 to 2 years through cost savings in operating and maintenance expenses.
Savings continue to accrue from the more efficient use of chemicals, avoiding over- and underfeeding,
and from lower labor costs for water testing and repairs of damaged equipment. In particular,
commercial operators save on specialty chemicals, customer complaints and health department
shutdowns.
EASY TO INSTALL
Installation of the CHEMTROL 250 is as easy as 1-2-3.
1. CONTROLLER - Connect the controller to the 110 or 230V output of the Timer in parallel to
the recirculation pump. This will prevent accidental feeding of chemicals when the pump is not
running. Make sure to follow the electrical code.
2. SENSORS - Install the ORP and pH sensors on the recirculation line or on the optional bypass
line. The two sensors can be mounted directly on the main recirculation line with 2" PVC tees,
as shown on the schematic. For recirculation lines over 2" in diameter lines, the sensors should
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CHEMTROL 250 ORP/pH Digital Controller
be mounted on a 1/2" bypass line.
3. CHEMICAL FEEDERS - Connect the chemical feeders to the 110 or 230V controller outputs,
according to the manufacturer's instructions, making sure to inject the chemicals downstream of
the sensors. For a bromine or chlorine erosion feeder, install a corrosion-resistant solenoid valve
on the intake line of the feeder. The controller is compatible with most ozonators and electrolytic
generators.
Flow Cell Assembly
For best operation, it is recommended to install the sensors on a bypass line with a Flow
Cell Assembly (FCA) as shown below.
The FCA includes a see-through cell with a plastic cover that regulates the flow of water
and allows the operator to see the tip of the sensors.
The cell includes the following:
1. two 1/2" FPT fittings for the connections to the bypass line,
2. two 1/2" FPT fittings for mounting the sensors,
3. a spigot for water testing,
4. a bleed line to prevent air lock in the cell,
In addition it is also recommended to install a safety switch on the bypass line to prevent
accidental feeding of chemicals.
SIMPLE TO OPERATE
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CHEMTROL 250 ORP/pH Digital Controller
The CHEMTROL®250 ORP/pH Digital Controller automatically maintains both
sanitizer ORP (oxidation-reduction potential or Redox) and water pH in pools and spas.
All operating functions are clearly labeled and accessible from the front panel, with many
safety and easy-reset features not found on other controllers:
●pH calibration from 4 to 10,
●ORP setpoint from 400 to 900 mV,
●pH setpoint from 4 to 10,
●ORP and pH feed modes: off, manual, automatic,
●ORP and pH proportional control bandwidth from 0 to 100% of the setpoint,
●ORP high and low alarms from 400 to 900 mV,
●pH high and low alarms from 4 to 10,
●ORP overfeed safety timer from 0 to 999 minutes,
●pH overfeed safety timer from 0 to 99 minutes.
To select a function, simply press ORP or pH and then the desired function. The display
shows the current function value. Use the UP or DOWN arrows to adjust to the desired
value.
CONTROL SETPOINTS
The standard factory-set ORP control level is 700 mV, based on WORLD HEALTH
ORGANIZATION (WHO) and NATIONAL SPA AND POOL INSTITUTE (NSPI)
values for prevention of germs and bacteria.
The standard factory-set pH control level is 7.5. Below 7.4, the water causes eye irritation
and corrosion of equipment. Above 7.6, it also causes eye irritation plus water cloudiness,
scaling, stains and reduced sanitizer efficiency.
To change the control levels, the operator presses ORP or pH and then SETPOINT. Use
the UP or DOWN arrows to adjust the ORP and pH setpoints. To save the new setpoint
value and exit, press SETPOINT again.
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CHEMTROL 250 ORP/pH Digital Controller
The controller then automatically activates the chemical feeders for sanitizer and acid (or
soda) feed, as required to maintain the set ORP and pH levels - regardless of fluctuations
in bather load, contamination and weather. Like a thermostat maintaining a constant
temperature, it prevents overfeeding or underfeeding, both of which are detrimental to
good water quality.
ALARMS
When there is an alarm condition, the corresponding display flashes the alarm value:
●ORP out-of-range,
●pH out-of-range,
●ORP overfeed,
●pH overfeed.
The display stops flashing when the condition is corrected. To reset the overfeed timers,
turn the feed mode to off and then back to Manual or Auto.
RESET
The ideal values are set as default values. They can be adjusted by the operator at any
time. To reset all factory default values, press ORP and pH for 5 seconds.
SPECIFICATIONS
ORP CONTROL Adjustable from 400 to 900 mV
pH CONTROL Adjustable from 4.0 to 10.0
ORP SENSOR Platinum electrode with 10-ft (3 m) cable
pH SENSOR Glass electrode with 10-ft (3 m) cable
READOUTS ORP (3 digits) and pH (2 digits) LEDs
FEED MODES Manual, automatic, proportional
ADJUSTMENTS Setpoint, calibration, limits, feed rate
INDICATORS LEDs for feed mode, feed status, alarms
SAFETY Audio, visual and remote alarms
Out-of-range limits and overfeed safety timers
CABINET Polystyrene 9x7x4 in. (22x18x10 cm)
ELECTRICAL 110V, 230V or 24 VAC (specify)
PLUMBING PVC tees for 1-1/2" or 2" line
WARRANTY 5 years on electronic module
1 year on all other parts
SHIPPING 12x12x12-in (30x30x30 cm) carton
8 lbs (3 kg) without pumps
16 lbs (6 kg) with 2 chemical feed pumps
BROCHURE FOR PRINTING
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CHEMTROL 250 ORP/pH Digital Controller
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