User Guide

HOLBY TEMPERING VALVE
APPLICATION
The HOLBY TEMPERING VALVE is a temperature regulating valve, designed to be used as a master, zone, fixture or
individual appliance regulator to control the predetermined temperature of hot water. Water delivered from hot water
generating equipment such as boilers, heat exchangers, submerged coils, or any other source is frequently too hot or
scalding. This condition can be corrected by the installation of a HOLBY TEMPERING VALVE.
The HOLBY TEMPERING VALVE is also used in regulating temperatures of engines, heating systems, compressors, cooling
towers, processing machinery and many other applications. The HOLBY TEMPERING VALVE IS NOT AN ANTI-SCALD
VALVE.
DESCRIPTION
The HOLBY TEMPERING VALVE is rugged, constructed entirely of bronze and copper and hydrostatically tested to a
pressure of 300 psig. It has the following features:
1. A long mixing chamber with vanes at an angle to the longitudinal axis of the valve which provides thorough mixing of
the hot and cold water.
2. The thermostatic element is placed inside the body of the valve where the hot and cold water mix. It is immediately
sensitive to any change in water temperature and makes proper corrections by opening or closing the hot and cold
water inlets in the valve.
3. A long thermostatic element provides fifteen to twenty times the number of corrugations found in the usual short
thermostat. Thus, the total expansion is divided over these numerous corrugations, so that the flexing of each is
reduced to mere thousandths of an inch resulting in long life of the instrument.
4. The action of the thermostatic element moves a piston over the hot and cold water openings, opening the cold as it
reduces the opening of the hot, thus uniformly blending the hot and cold water, producing an even temperature of the
delivered water without any change in volume. This action eliminates the building up of temperature in circulating
systems at times when little or no hot water is being used.
5. Large hot and cold water passages result in very low pressure drop through the valve.
6. Complies with ASSE Standard #1017-2009.
INSTALLATION
The HOLBY TEMPERING VALVE will operate satisfactorily when installed in any position. Valve installation must follow the
HOLBY basic piping diagrams. The adjusting screw end of the valve should not be placed against, nor in-line with any other
fixed object for a (minimum) space of twenty-four inches. This clearance is required for service access to the internal valve
parts. Warranty is only valid for proper installations.
SERVICE and MAINTENANCE
The HOLBY TEMPERING VALVE should be opened, inspected and cleaned within one year of initial installation. A routine
inspection and service schedule should be implemented depending on the system water quality.
TEMPERATURE RANGE
The HOLBY TEMPERING VALVE can be adjusted to deliver water within close tolerances of any temperature from 120° to
200° Fahrenheit provided that the hot water supplied to the valve is of a higher temperature than that for which the valve is
set. Higher or lower temperature ranges are available on special order. For outlet temperatures below 120° Fahrenheit,
please specify for low temperature operation.
REGULATION
The temperature of the water delivered by the HOLBY TEMPERING VALVE can be changed by turning the adjusting screw
clockwise for lower temperatures and counter-clockwise for higher temperatures. To facilitate adjustment a thermometer
should be placed in the outlet line as shown in the diagram and water should be flowing through the HOLBY TEMPERING
VALVE while adjustments are being made.
FUNCTIONS
1. To mix hot and cold water and control the mixed water temperature within close tolerances between 120° and 200°
Fahrenheit. Other temperature ranges are available upon request.
2. To prevent elevated hot water temperatures during off-peak periods. As hot water enters the HOLBY TEMPERING
VALVE the thermostat closes the hot water inlet and opens the cold water inlet allowing hot water re-circulation flow
through the HOLBY TEMPERING VALVE thus controlling the rate of re-circulation to the hot water supply line.
3. To increase the capacity of water heating systems by automatically introducing cold water to the hot water lines and
delivering a blended mixture at the desired temperature.
4. To deliver water at different temperatures to various locations from one hot water source.