TJERNLUND WHK2 MILLIVOLT APPLIANCE INTERLOCK INST. (NOT COMPATIBLE WITH UC1) 8504026 REV A 0600 Manual

TJERNLUND PRODUCTS, INC.
1601 Ninth Street • White Bear Lake, MN 55110-6794
PHONE (800) 255-4208 • (651) 426-2993 • FAX (651) 426-9547
Visit our web site • www.tjernlund.com
IMPORTANT: This gas pressure switch is an updated version with only one 1/4" aluminum
tubing connection to the pressure tap port of gas valve. The atmospheric vent connection
is no longer required, as on the Old-Style Switch. Disregard the "Gas Pressure Switch"
installation section of your VP-2/3, WHK-2, WHKE instruction manual if the old style switch
is referenced, (See Discontinued Old-Style Switch Diagram). If you are replacing an Old-
Style gas pressure switch with the new style gas pressure switch follow the instructions
below. The new style switch is compatible with any previous Old-Style Switch installations.
Qty (1) gas pressure switch
Qty (1) 1/8-NPT black pipe tee
Qty (2) #10 x ½" self-tapping screws
The gas pressure switch is mounted on the casing of the water heater adjacent to the heater's thermostat/gas control valve. It
should be mounted close enough so that the supplied 1/4" tubing will reach from the gas pressure switch fitting to the thermo-
stat/gas valve pressure tap port. The two provided screws are self-tapping and drilling. The screws do not require the use of a
drill and their 1/2" length assures that the inner tank will not be penetrated.
1. Mount the gas pressure switch by securing it to the heater casing with a screw in each of the two mounting holes.
IMPORTANT: Mount gas pressure switch so that diaphragm is in a VERTICAL position, (See New Switch Diagram).
2. Install the supplied 1/8"-NPT pipe plug to the 90
thread sealant, do not over tighten.
3. Install the 1/8-NPT black pipe tee to the gas pressure switch, (See New Switch Diagram). Use thread sealant, do not over
tighten. CAUTION: Utilize the hex nut on the gas pressure switch when attaching the black pipe tee.
4. Install the supplied Brass 1/8-NPT male x ¼" compression fitting to the 1/8-NPT black pipe tee, (See New Switch Diagram ).
Use thread sealant, do not over tighten.
5. Remove the PRESSURE TAP plug from the underside of the thermostat/gas control valve and install the supplied Brass
1/8-NPT male x ¼" compression fitting, (See New Switch Diagram). Use thread sealant, do not over tighten.
IMPORTANT: DO NOT alter the heater's PILOT GAS LINE, (See New Switch Diagram).
6. Using a tube cutter, cut the appropriate length of the supplied 1/4" tubing to reach from the gas pressure switch fitting to the
PRESSURE TAP PORT fitting of the thermostat/gas control valve. Make sure each end of the tubing is not pinched closed.
7. Use the 1/4" tubing to connect gas pressure switch fitting to the PRESSURE TAP PORT fitting on the thermostat/gas control valve.
8. Conduct a gas leakage test of all connections as outlined in the latest edition of NFPA 54, ANSI Z223.1, part 4. or local codes.
NOTE: A "gauge port" can be accessed by removing the 1/8-NPT pipe plug that is on the 1/8-NPT black pipe tee (attached to
the gas pressure switch).
GAS PRESSURE SWITCH
COMMON
NORMALLY OPEN
Qty (1) 1/8-NPT pipe plug
Qty (2) brass 1/8-NPT male x ¼" compression fitting (Only (1) included in 950-2080 kit)
Qty (1) section of ¼" outside diam. aluminum tubing (Not included in 950-2080 kit)
NEW STYLE GAS PRESSURE SWITCH INSTALLATION
port of the supplied 1/8-NPT black pipe tee, (See New Switch Diagram). Use
o
New-Style Gas Pressure
Switch Installation
MOUNTING HOLES
1/4" OUTSIDE DIAMETER
ALUMINUM TUBING - CONNECT
TO PRESSURE TAP FITTING OF
THERMOSTAT / GAS CONTROL
VALVE.
©2004 TJERNLUND PRODUCTS, INC. ALL RIGHTS RESERVED
THERMOSTAT/
GAS CONTROL VALVE
GAS SUPPLY
THERMOCOUPLE
BURNER GAS LINE
Discontinued Old-Style Switch
IMPORTANT:
DO NOT ALTER
PILOT GAS LINE
INSTALL BRASS 1/8-NPT MALE
x 1/4" COMPRESSION FITTING
INTO PRESSURE TAP PORT.
FIGURE 700S107
P/N: 8505022
2/13/04