Controls
The Raypak modulating temperature control is pro-
vided to maintain the desired system water
temperature. The control has various modes of opera-
tion which are described on the following pages.
The
XTherm
is
designed
for
use
with
Primary/Secondary pumping only, utilizing integral
injector pumps to maintain proper flows and tempera-
tures in the heater.
Setpoint:
The intended system supply temperature.
Deadband:
Deadband is a band of temperature sens-
ing where no action occurs. All temperature controllers
have a deadband and the purpose is to prevent short-
cycling of the heater. The on-board temperature
controller has a deadband of 2ºF around the differen-
tial.
Differential:
A heat source must be operated with a
temperature differential in order to prevent short-
cycling. The temperature differential is divided around
the “target” temperature or set-point. The Call For Heat
(CFH) contact will close in the controller when the
water temperature is below the target temperature by
1/2 of the differential setting, and will open when the
water temperature is above the target temperature by
1/2 of the differential setting. See Fig. 34.
32
CAUTION:
Risk of electric shock: More than one
disconnect switch may be required to de-energize
the equipment before servicing.
CAUTION:
This appliance has provisions to be
connected to more than one supply source. To
reduce the risk of electric shock, disconnect all such
connections before servicing.
Fig. 32: Adapter Thimble
Crimp end to be installed into termination cap.
Fig. 33: Termination using Adapter Thimble
WARNING:
Installation, adjustment and service of
heater controls, including timing of various operating
functions, must be performed by a qualified installer,
service agency or the gas supplier. Failure to do so
may result in control damage, heater malfunction,
property damage, personal injury, or death.
WARNING:
Turn off the power to the heater before
installation, adjustment or service of any heater
controls. Failure to do so may result in board
damage, heater malfunction, property damage,
personal injury, or death.
Summary of Contents for Xtherm 1005
Page 42: ...42 WIRING DIAGRAMS Models 1005 1505 ...
Page 43: ...43 Model 2005 ...
Page 58: ...58 ...
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