Chromalox PK477 Prospecto
PK477
161-506096-001
JUNE, 1995
4WT
Installation Instructions
(Supersedes PK477)
Type WT Room Thermostat
© 2010 Chromalox, Inc.
GENERAL
Note: Type WT thermostats are designed for temperature control
service only. Because they do not fail safe, they should not be used
for temperature limiting duty.
service only. Because they do not fail safe, they should not be used
for temperature limiting duty.
WARNING: Users should install adequate back-up
controls and safety devices with their electric
heating equipment. Where the consequences of
failure may be severe, back-up controls are essen-
tial. Although the safety of the installation is the
responsibility of the user, Chromalox will be glad to
make equipment recommendations.
controls and safety devices with their electric
heating equipment. Where the consequences of
failure may be severe, back-up controls are essen-
tial. Although the safety of the installation is the
responsibility of the user, Chromalox will be glad to
make equipment recommendations.
WARNING: Not for use in hazardous environments
as described in the National Electrical Code.
Failure to comply can result in explosion or fire.
as described in the National Electrical Code.
Failure to comply can result in explosion or fire.
Thermostat Location
1. Mount in any standard electrical outlet box. Use of extra deep
1. Mount in any standard electrical outlet box. Use of extra deep
box (3” x 2” x 3
1
/
2
”) makes for easier wiring.
2. Locate outlet box about 5’ above floor on inside wall.
3. Box location should be representative of the area to be con-
3. Box location should be representative of the area to be con-
trolled. Avoid locations that are subject to drafts or false exter-
nal heat (such as solar radiation, direct heat from heaters, etc.).
Insure that the wall selected is capped to prevent drafts within
the wall.
nal heat (such as solar radiation, direct heat from heaters, etc.).
Insure that the wall selected is capped to prevent drafts within
the wall.
Temp
Maximum Rating
Range
Contacts
Model
(°F)
128V AC
208V AC
240V AC
277V AC
Pilot Duty
125V AC
WT-121
45-75
SPST
22 amps
22 amps
22 amps
18 amps
(use with
or 2640
or 4575
or 5280
or 5000
AC
WT-122
45-75
DPST
total watts
total watts
total watts
total watts
contactor)
Specifications — Table A
4.72"
(110)
Front View
2.14"
(54)
Side View
2.86"
(73)