Thermostatic Head And Modulating Valve; Bypass Orifice (Individual Control) - L.B.White I-17 Manual Del Usuario E Instrucciones

22
I-17 / I-40 Manual and Spark Ignition
THERMOSTATIC HEAD AND
MODULATING VALVE
Individual Control Heaters and
Modulating Zone Panels
■ The head assembly includes the adjustable
thermostatic head, capillary and sensor. The part
numbers for the thermostatic heads are:
-- Zone panel head: Part No. - 09416 w/ 26 ft.
capillary
-- Individual control head: Part No. - 509415 w/ 6 ½
ft. capillary
During normal operation, the thermostatic head
gradually increases or decreases force against the
modulating valve pin to allow more or less gas pres-
sure to the combustion cones.
If the thermostatic head is set to a lower tempera-
ture but the heat output from the combustion cones
does not decrease, refer to the following.:
-- Loosen the attachment knob located at the ther-
mostatic head and valve body so the valve pin is
exposed. See Fig. 16.
-- Using a tool such as the flat of a standard screw-
driver, firmly but gradually push down on the pin
of the modulating valve.
-- If the heat does not decrease or you must use
significant pressure to force the pin, the valve
is sticking and needs replacement. Ensure flow
arrow on valve follows gas flow.
-- If the heat does decrease when the pin is pushed,
the thermostatic head is defective. The head is
available only with capillary with sensor.
FIG. 16
Owner's Manual • I-17 / I-40
The attachment knob at the head must be securely
threaded onto the valve body, otherwise tempera-
ture sensing will be affected.
The head's sensor and capillary must be positioned
above animal height to avoid contact and subse-
quent damage by livestock.
BYPASS ORIFICE
Individual Control Heaters
The bypass orifice is located in the valve body of
the individual controlled heaters. Its purpose is to
supply low pressure gas to the inner combustion
cone when heat demand is satisfied.
The orifice may become plugged with dirt after
significant heater use. A typical symptom of a
plugged orifice are:
-- Inner cone goes out when thermostatic head
cycles heater back to low heat.
Refer to the following instructions:
1. Apply wrenches to the flats of the valve body and
the adapter nut. See Fig. 17.
2. Loosen the adapter nut at the outlet of the valve
body. See Fig. 17.
3. Pull the control assembly with adapter and
adapter nut from the valve body.
4. Using a 3/16 in. nut driver, remove the orifice
from valve body. See Fig. 18. Clean or replace if
necessary. At reinstallation, do not overtighten as
thread damage may occur.
FIG. 17
HOSE
ADAPTER
Thermostatic Head
Attachment Knob
FIG. 18
Valve Pin
Modulating Valve
ADAPTER NUT
VALVE BODY
ADAPTER
FLATS
THERMOSTATIC HEAD
LOW FIRE ORIFICE
THERMOSTATIC
HEAD