Honeywell L4008 Manuale Utente

Pagina di 20
L4006,7,8; L6006,7,8 AQUASTAT
®
 CONTROLLERS
15
60-2104—10
Fig. 29. Operation of L6008G.
Fig. 30. Operation of L4008L.
Low Limit Controller
R-B terminals provide low limit switching function (contacts 
open at set point on temperature rise). Maintains minimum 
boiler temperature for domestic hot water. Turns on boiler at 
temperature setting, less differential.
Circulator Controller
R-W terminals provide circulation control function (contacts 
close at set point on temperature rise). Prevents circulation of 
water that is below the desired heating temperature. Breaks 
circulator circuit on temperature drop below setting less 
differential; remakes on rise to setting.
L6008G Adjustable Interstage Differential
When the temperature at the sensing element rises above the 
set point of the controller, the switch on the right makes R-W. If 
the temperature continues to rise through the preselected 
interstage differential of the controller, the switch on the left 
makes R-W.
Conversely, on a temperature fall, the switch on the left makes 
R-B, providing first step switching. If the temperature continues 
to fall, the switch on the right makes R-B to provide sequencing 
of equipment.
ADJUSTMENTS
Adjusting Differential
Set the differential to correspond with the boiler manufacturer 
recommendations. To adjust models with adjustable 
differential, rotate the wheel on the back of the snap switch, 
(See Fig. 32), until the desired reading is aligned with the 
V notch in the frame. The wheel provides an adjustment from 
5° F to 30° F (3° C to 17° C). Replace the cover on the 
Aquastat Controller.
Fig. 31. Adjusting the differential.
TEMPERATURE
RISE
SETPOINT
(ADJUSTABLE)
LEFT SWITCH
DIFFERENTIAL
RIGHT SWITCH
DIFFERENTIAL
BREAKS R-B
MAKES R-W
ON RISE
BREAKS R-B
MAKES R-W
ON RISE
BREAKS R-W
MAKES R-B
ON FALL
BREAKS R-W
MAKES R-B
ON FALL
INTERSTAGE 
DIFFERENTIAL
DIFFERENCE BETWEEN THE TEMPERATURES AT WHICH THE 
TWO SWITCHES MAKE R-W.  ADJUSTABLE FROM 3°F TO 10°F 
(1.7°C  TO 5.6°C) ON STANDARD MODELS, OR FROM 3.6°F TO 12°F 
(2.0°C  TO 6.7°C); 55°F TO 175°F (13°C TO 79°C) MODELS.
TWO SPDT SWITCHES OPERATE IN SEQUENCE.  EACH SWITCH
DIFFERENTIAL IS FIXED AT APPROXIMATELY 3°F (1.7°C) ON
STANDARD MODELS, OR AT 3.6°F (2.0°C); 55°F TO 175°F (13°C TO
79°C) MODELS.
1
2
1
2
2
M2999B
TEMPERATURE
RISE
SETPOINT
(ADJUSTABLE)
LEFT SWITCH
DIFFERENTIAL
RIGHT SWITCH
DIFFERENTIAL
BREAKS
ON RISE
BREAKS
ON RISE
MAKES
ON FALL
MAKES
ON FALL
INTERSTAGE 
DIFFERENTIAL
DIFFERENCE BETWEEN THE TEMPERATURES AT WHICH 
THE TWO SWITCHES BREAK ON TEMPERATURE RISE.
SWITCHES OPERATE IN SEQUENCE.  RIGHT SWITCH 
FIRST-ON TEMPERATURE RISE.
1
2
1
2
2
M4671A
M8969
DIFFERENTIAL
WHEEL
NOTCH IN
FRAME
SNAP
SWITCH
SELECT MODELS HAVE A SCREW TERMINAL INSTEAD 
OF TAB TERMINAL.
1
1