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. Municipal Pools

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 Set Points
	Adjustable High and Low Alarms,
	Adjustable Overfeed Safety Timers,
	Adjustable Proportional Feed Control.

We carry all aspects of the system.

	Chemical Feed Pumps
	Chemical Storage Tanks for the use of Sodium Hypochlorite
	CO2 Controllers for pH Control

FEATURES

	Easy to install
	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 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.

Simple to Operate

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 set points. To save the new setpoint value and exit, press SETPOINT again.

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

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