DriSteem VAPOR-LOGIC 3 User manual

Vapor-logic®3
to Vapor-logic4
Adaptor Board
Installation Manual

Page ii • DRI-STEEM Vapor-logic3 to Vapor-logic4 Adaptor Board Installation Manual
WARNING
Indicates a hazardous situation that could result in death or serious
injury if instructions are not followed.
CAUTION
Indicates a hazardous situation that could result in damage to
or destruction of property if instructions are not followed.
mc_051508_1145
WARNING
Read all warnings and instructions
This page provides important safety instructions; it is intended to supplement — not replace — the humidifier's Installation,
Operation, and Maintenance Manual (IOM). Read the IOM that was provided with the humidifier before performing service or
maintenance procedures on any part of the system. Failure to follow all warnings and instructions could produce the hazardous
situations described here and in the IOM, resulting in property damage, personal injury, or death.
If the IOM is missing, go to http://www.dristeem.com/ds_lit.jsp to download a replacement.
mc_071608_0910
Hot surfaces and hot water
Steam humidification systems have extremely hot surfaces, and water in tanks, electrode cylinders, steam pipes, and dispersion
assemblies can be as hot as 212 °F (100 °C). To avoid severe burns, allow the entire humidification system to cool.
Follow the cool-down procedure in the humidifier's IOM before performing service or maintenance procedures on any part of the
system.
mc_071608_0911
Shut down the energy source
Before performing service or maintenance procedures on any part of the humidification system, verify that all energy sources
are off. Energy sources can be electricity, gas, steam, or hot liquid. Failure to shut down the energy source could result in carbon
monoxide poisoning, fire, explosion, electrical shock, and other hazardous conditions. These hazardous conditions could cause
property damage, personal injury, or death.
Contact with energized circuits can cause property damage, severe personal injury or death as a result of electrical shock or fire.
Do not remove the shroud/cover, electrical panel cover/door, access panels, or heater terminal cover until electrical power is
disconnected.
Follow the shutdown procedure in the humidifier's IOM before performing service or maintenance procedures on any part of the
system.
mc_050808_1551
Warnings and cautions
Warnings and cautions

DRI-STEEM Vapor-logic3 to Vapor-logic4 Adaptor Board Installation Manual • Page 1
Table of contents
Warnings and cautions ................................ ii
Before beginning the upgrade........................... 2
Parts ............................................... 2
GTS humidifiers:
Board removal and replacement
Removing Vapor-logic3, installing Vapor-logic4. . . . . . . . . . . . . 3
Transferring expansion board terminal blocks ..............5
Keypad/display removal and replacement
Indoor GTS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
GTS with outdoor enclosure ..............................6
Safety circuit wiring
Leave safety circuit wired in series with one alarm ...........8
Separate safety circuit alarm signals into three alarms ........8
Electric humidifiers:
Board removal and replacement
Removing Vapor-logic3, installing Vapor-logic4. . . . . . . . . . . . 10
Transferring expansion board terminal blocks .............12
Keypad/display removal and replacement
Vaporstream and CRUV with mounted keypad/display .....13
Vaporstream and CRUV with unmounted keypad/display ...13
Vapormist and Humidi-tech .............................13
Safety circuit wiring.......................................14
STS humidifiers:
Board removal and replacement ............................16
Keypad/display removal and replacement
STS with mounted keypad/display ........................18
STS with unmounted keypad/display .....................18
Safety circuit wiring.......................................18
All Humidifiers:
Start-up and validation
Start-up ...............................................19
Test outputs ...........................................19
Test run...............................................19
Vapor-logic4 adaptor board pin descriptions ........ Back cover
Tools required:
• Needle nose pliers / wire cutter
• Wire stripper
• #2 Phillips screwdriver
• 3/16" and 1/8" flat-tip screwdrivers
• 5/8" nut driver

Page 2 • DRI-STEEM Vapor-logic3 to Vapor-logic4 Adaptor Board Installation Manual
Parts
Make sure all parts listed below are included in the Vapor-logic3 to
Vapor-logic4 upgrade kit you received.
Table 2-1:
Vapor-logic3 (VL3) to Vapor-logic4 (VL4) adaptor board kits
Part No. 183503-001
CRUV®, GTS®04 indoor, GTS99 indoor, GTS99 outdoor, Humidi-tech®, STS®,
Vapormist®, and Vaporstream®
No. Description Qty.
1VL3 to VL4 adaptor board 1
2 Mounting stand-off* for adaptor board 6
3VL4 keypad/display 1
4 Molex®plug (installed on adaptor board) 2
5 Jumper for configuring safety alarms 1
6 Field conversion label** 1
7 Ferrite core (required for Humidi-tech humidifier) 1
Part No. 183503-002
GTS04 outdoor with 46.5" (1180 mm) enclosure door height
(before March 2007)
No. Description Qty.
1VL3 to VL4 adaptor board 1
2 Mounting stand-off* for adaptor board 6
3VL4 keypad/display, fan, and bracket 1
4 Molex®plug (installed on adaptor board) 2
5 Jumper for configuring safety alarms 1
6 Outdoor enclosure replacement door 1
7 Field conversion label** 1
Part No. 183503-003
GTS04 outdoor with 51" (1295 mm) enclosure door height
(March 2007 and later)
No. Description Qty.
1VL3 to VL4 adaptor board 1
2 Mounting stand-off* for adaptor board 6
3VL4 keypad/display, fan, and bracket 1
4 Molex®plug (installed on adaptor board) 2
5 Jumper for configuring safety alarms 1
6 Outdoor enclosure replacement door 1
7 Field conversion label** 1
* For extra stand-offs, order Part No. 409595.
** For extra labels, order Part No. 800076.
Figure 2-1:
Matching pin numbers on board and
terminal block
Before beginning the upgrade
Do not disconnect wires
Do not disconnect wires from terminal blocks.
Terminal blocks connect to pin locations with
matching pin numbers (see Figure 2-1). Match
numbers to avoid reversing terminal blocks.
Before disconnecting power
• Verify that the humidifier is operating
correctly; check the Vapor-logic3 display
for alarms and messages.
• Write down the Vapor-logic3 configuration
string. This may help during start-up
and commissioning after upgrading
to Vapor-logic4. See the Vapor-logic3
Installation and Operation manual for
details on how to obtain the configuration
string.
• If upgrading an outdoor GTS, verify that
the new enclosure door is the same height
as the old door.
Before beginning the upgrade

DRI-STEEM Vapor-logic3 to Vapor-logic4 Adaptor Board Installation Manual • Page 3
Figure 3-1:
GTS subpanel
VL3 main board* VL3 GTS expansion boards*
Top wire channelRibbon cables*
Keypad/display
cable
* Not re-used
Removing Vapor-logic3, installing Vapor-logic4
1. If upgrading an outdoor GTS®, complete Steps 1 through 3 in “GTS
with outdoor enclosure” on Page 6 before proceeding.
2. Remove GTS control access panel to access the subpanel, shown in
Figure 3-1.
3. Disconnect Vapor-logic3 keypad/display cable and ribbon cables
from Vapor-logic3 main board and expansion board(s). Ribbon
cables will not be re-used.
4. Torque all terminal block screws to 2.5 in-lb (0.28 N·m) to prevent
wires from pulling loose in Step 5.
5. Mark location of Vapor-logic3 main board on subpanel by making
corner marks on subpanel with felt-tipped marker.
6. Use pliers to pull terminal blocks from Vapor-logic3 main board.
Unscrew stand-offs, and remove board and stand-offs (they will not
be re-used).
7. Leaving adhesive backing paper on the six nylon stand-offs
packaged with Vapor-logic4 adaptor board, push stand-offs into
adaptor board mounting holes, as shown in Figure 3-2.
WARNING
Shut down humidifier
Before performing any maintenance or
service procedures, shut off all electrical
power to humidifier using field-installed
fused disconnect, lock all power
disconnect switches in OFF position, and
close the gas shut-off valve.
GTS humidifiers:
Board removal and replacement
Figure 3-2:
VL4 adaptor board stand-offs
Bottom of VL4 adaptor board shown
Stand-off

Page 4 • DRI-STEEM Vapor-logic3 to Vapor-logic4 Adaptor Board Installation Manual
GTS humidifiers:
Board removal and replacement
Figure 4-1:
Vapor-logic boards
20191817 24232221
7 8 9 101 2 3
16151411 12 13
GTS EXPANSION BOARD 1
GTS EXPANSION BOARD 2
P1P2P3P4P5P6P7P8
P19P18P17P16P15P14P13P12P11
65 87 109 1211 1413 15 1918 20 2321 22 2624 25 2927 28
GTS
31 303233
65
VLC EXPANSION
LON ProtoCessor Module
T2 T1 T1T2T2 3435
1 2 43
7 8 9 101 2 3
20191817 24232221
P21A
P21B
34
VLC
6 5 124 3
T1
1 2 43 65 87 109 1211 1413 15 1918 20 2321 22 2624 25 2927 281716
31 3034 323335
AB
EXPANSION
T2 T1 T1T2T2
VL3
keypad
LonTalk ®
network
LonTalk
®
VL3 main board
VL4 adaptor board (two stacked boards; top board shown)
8. Plug Vapor-logic4 keypad/display cable into Display connection on
Vapor-logic4 adaptor board (see Figure 4-1). If present, plug laptop
or network cable into Ethernet connection on adaptor board.
9. If upgrading to Vapor-logic4 without LonTalk® interoperability
(see Figure 4-2), skip this Step. If upgrading to Vapor-logic4 with
LonTalk interoperability, disconnect wires from Vapor-logic3
LonTalk pins and land them as instructed in Table 4-1.
Table 4-1
Landing LonTalk wires
Disconnect wire from this
Vapor-logic3 board LonTalk pin
Connect it to this pin on Vapor-logic4
adaptor board LON ProtoCessor Module
Ground Ground pin P1-2, P2-4, P4-3, P6-3, or P19-3
AP21A
BP21B
Figure 4-2:
Determining LonTalk interoperability
Corner of VL3 main board shown
VL3 board LonTalk connections
(if no wires, then no LonTalk)
Laptop or network connection
(Ethernet connection on bottom board)
VL4 keypad connection
(Display connection on bottom board)
The Vapor-logic4 adapter board pin descriptions
are listed in Table 20-1 on the back cover.

DRI-STEEM Vapor-logic3 to Vapor-logic4 Adaptor Board Installation Manual • Page 5
Figure 5-1:
Splitting interlocked terminal blocks
10. Make sure subpanel surface is clean and dry. Remove adhesive
backing paper from new stand-offs, and press adaptor board into
exact location where Vapor-logic3 board was mounted.
11. Land loose Vapor-logic3 terminal blocks on corresponding pin
locations of Vapor-logic4 adaptor board.
Notes: Some 4-pin terminal blocks are two interlocked 2-pin
blocks that will need to be split. See Figure 5-1.
Scrape away any pin hole or screw corrosion before landing
terminal blocks on Vapor-logic4 adapter board.
Not all Vapor-logic3 wire connections will be used for this
upgrade. Cap bare ends of unused wires with wire nuts,
and tuck them into wire channel.
12. Cut an 18-gauge, stranded wire long enough to reach terminals T2
and 33 on Vapor-logic4 adaptor board (Figure 5-2). Strip ends of
wire, land ends at terminals T2 and 33, and torque terminal screws
to 2.5 in-lb (0.28 N·m).
13. Configure either modulating or on-off duct high limit:
• Modulating: Move Vapor-logic3 terminal block 24/25/26 to Pins
24/25/26 on Vapor-logic4 adapter board.
• On-off: Move wire from Vapor-logic3 Pin 26 to Pin 24 of same
terminal block. Then move terminal block to Pins 24/25/26 on
Vapor-logic4 adapter board.
Transferring expansion board terminal blocks
Leave the wires in the terminals when transferring the terminal blocks
from the Vapor-logic3 expansion board(s) to the Vapor-logic4 adaptor
board.
Note: To facilitate wire re-routing and provide slack, remove top wire
channel cover. Unbundle wires as necessary in channel and in
wiring harness leading to burners.
GTS humidifiers have one or two Vapor-logic3 expansion boards.
If upgrading from Vapor-logic3 with two expansion boards, land
terminal blocks from one expansion board at a time.
Vapor-logic4 adaptor board pin locations for Vapor-logic3 expansion
board terminal blocks are labeled     and 
  , as shown in Figure 4-1.
Figure 5-2:
Jumpering terminals T2 and 33
Jumper
T2 33
Top edge of VL4
adaptor board
GTS humidifiers:
Board removal and replacement

Page 6 • DRI-STEEM Vapor-logic3 to Vapor-logic4 Adaptor Board Installation Manual
Indoor GTS
1. Remove GTS end panel (Figure 6-1) to access keypad/display
mounting screws.
2. Remove the four keypad/display mounting screws, and disconnect
cable from Vapor-logic3 keypad/display. Vapor-logic3 keypad/
display will not be re-used.
3. Plug cable into Vapor-logic4 keypad/display, position Vapor-logic4
keypad/display over opening, and tighten mounting screws.
4. Replace GTS end panel.
GTS with outdoor enclosure
Outdoor GTS humidifiers require the following hardware changes to
provide clearance for the ventilation fan:
1. Remove outdoor enclosure door that matches height of
replacement door shipped with upgrade kit. Screws will be re-used,
but not door.
2. Unplug power connection at fan, and remove fan and bracket
(Figure 7-1). Fan and bracket will not be re-used.
3. Unclip Vapor-logic3 keypad/display from bracket, unplug cable,
and remove bracket. Bracket and Vapor-logic3 keypad/display will
not be re-used.
4. Mount Vapor-logic4 keypad/display, fan, and bracket assembly on
subpanel. Use mounting screws provided and existing mounting
screw holes (see Figure 7-2).
5. Unclip Vapor-logic4 keypad/display from bracket, plug in cable,
and replace keypad/display on bracket.
6. Connect fan power using plug from Step 2, above.
7. Replace outdoor enclosure door with new door shipped with
upgrade kit. Re-use screws from Step 1.
Figure 6-1:
Keypad/display mounting screws
(indoor GTS)
Remove end
panel for access
to keypad/
display mounting
screws inside
of side panel.
OM-1222X
GTS humidifiers:
Keypad/display removal and
replacement

DRI-STEEM Vapor-logic3 to Vapor-logic4 Adaptor Board Installation Manual • Page 7
GTS humidifiers:
Keypad/display removal and
replacement
GTS04PNLASM-50view
Figure 7-1:
VL3 keypad/display, fan, and brackets (outdoor GTS)
Remove fan and bracket
assembly
Remove VL3 keypad/display and
bracket assembly
Install VL4 keypad/display,
fan, and bracket assembly
Mounting screws (use
existing holes)
GTS04PNLASM-50_testwVL4view
Figure 7-2:
VL4 keypad/display, fan, and bracket assembly (outdoor GTS)

Page 8 • DRI-STEEM Vapor-logic3 to Vapor-logic4 Adaptor Board Installation Manual
GTS humidifiers:
Safety circuit wiring
Certain Vapor-logic3 alarm points are wired in series and register as
“Interlock Disable” when any of the following alarms is tripped: door
interlock, blocked flue, or low water.
Whether leaving alarm signals in series or separating them, you must
perform either the procedure at left or the procedure below.
Note: If needed, refer to the Vapor-logic3 wiring diagram and the
Vapor-logic4 Installation and Operation Manual for more
wiring information.
Separate safety circuit alarm signals into three alarms
• IfGTSdoesnothaveadoorinterlockswitch,performonlySteps
1 through 5 on Page 9.
• IfGTShasadoorinterlockswitch,performonlySteps1through8
below.
Note: Torque terminal block screws to 2.5 in-lb (0.28 N·m). Torque all
other terminal connections to 7 in-lb (0.79 N·m).
Door interlock switch (Figure 9-1)
1. Remove wire 414 from terminal 14 on Vapor-logic3 main board.
Remove other end of wire from position 11 on low water relay, and
keep for re-use in Step 8.
2. Remove wire 414A from position 14 on low water relay. Land this
wire at terminal 14 on Vapor-logic4 adaptor board.
3. Locate wire 415A running between door interlock switch and
blocked flue switch. Remove this wire from both termination
points, and keep for re-use in Step 5.
4. Locate wire 415 running between terminal 15 on Vapor-logic3
main board and blocked flue switch. Remove fork connector end
from blocked flue switch, and connect it to door interlock switch
where wire 415A was located.
Blocked flue switch (Figure 9-1)
5. Locate wire 415A that was removed in Step 3: Connect one fork
terminal to NC (normally closed) contact. Run wire to P3-4
connector at top of Vapor-logic4 adaptor board. Cut wire to length,
strip end, and land it at terminal P3-4.
6. Using other end of wire 415A that was removed in Step 3: Land
remaining fork terminal at the C (common) contact on blocked
flue switch. Strip other end, land it at one of the h terminals
(24Vac) on terminal strip at bottom of subpanel.
Low water circuit (Figure 9-1)
7. Locate wire 801 that runs to T1 terminal on expansion board that
was directly to the right of Vapor-logic3 main board. Remove end
of this wire, land it at position 11 on low water relay.
8. Locate wire 414 that was removed in Step 1. Land one end of this
wire at position 14 on low water relay. Land other end at terminal
P3-3 on Vapor-logic4 adaptor board.
24 VAC
801 h
T1
24 VAC
801
LW
P3
P3-3
P3-4
FPsw
h
Gray-handled
jumper provided
with upgrade kit
Figure 8-1:
Leaving safety circuit wired in series
with one alarm
DM-10097
DM-10098
Leave safety circuit wired in series with
one alarm
1. Make sure gray-handled jumper supplied
with upgrade kit is inserted into terminals
P3-3 and P3-4 on Vapor-logic4 adaptor
board (Figure 8-1).
2. Locate wire 801 that runs to expansion
board terminal T1, and land it at terminal
P3-3 on Vapor-logic4 adaptor board. If
wire 801 does not reach P3-3, use a longer
18-gauge, stranded wire. Torque terminal
block screws to 2.5 in-lb (0.28 N·m).
Proceed to “Start-up and validation” on
Page 19.
VL3 expansion board
VL4 adaptor board

DRI-STEEM Vapor-logic3 to Vapor-logic4 Adaptor Board Installation Manual • Page 9
Figure 9-1:
Separating safety circuit alarm signals (GTS with door interlock switch)
VL3 with door interlock
Low water relay
Blocked flue switch 415A
414A
415
414
24 VAC
801
Door interlock
Main board
Expansion board
11 14
NC
C
14
15
T1 h
VL4 adaptor board with door interlock
Low water relay
Blocked flue switch
24 VAC 801 414 LW
P3
P3-3
P3-4
FPsw
415A415A
Door interlock
414A
415
NC
C
14
15
h
11 14
h
DM-10099 DM-10101
GTS humidifiers:
Safety circuit wiring
The following steps are for GTS without door interlock switch:
Note: Torque terminal block screws to 2.5 in-lb (0.28 N·m). Torque all
other terminal connections to 7 in-lb (0.79 N·m).
Blocked flue switch (Figure 9-2)
1. Remove wire 414A from position 14 on low water relay. Land this
wire at terminal P3-4 at top of the Vapor-logic4 adaptor board.
2. Remove wire 415 from terminal 15 on Vapor-logic3 main board.
Land wire at one of the h terminals (24 Vac) on terminal strip at
bottom of subpanel.
Low water circuit (Figure 9-2)
3. Remove wire 414 from terminal 14 on Vapor-logic3 main board.
Remove other end of this wire from position 11 on low water
relay. Land one end of this wire at position 14 on low water relay.
Land other end of this wire at terminal P3-3 at top of Vapor-logic4
adaptor board.
4. Locate wire 801 that runs to T1 terminal on expansion board that
was directly to the right of Vapor-logic3 main board. Remove end
of this wire, and land it at position 11 on low water relay.
5. Insert gray-handled jumper supplied with this upgrade kit into
terminals 14 and 15 on Vapor-logic4 adaptor board.
Proceed to “Start-up and validation” on Page 19.
Figure 9-2:
Separating safety circuit alarm signals
(GTS without door interlock switch)
VL3 without door interlock
Low water relay
Blocked flue switch
24 VAC
801
Main board
Expansion board
415
414
414A
11 14
C NC
14
15
T1 h
VL4 adaptor board without door interlock
Low water relay
Blocked flue switch
24 VAC
801 414
414A415
11 14
C NC
LW
P3
P3-3
P3-4
FPsw
14
15
h
h
Gray-handled
jumper provided
with upgrade kit
DM-10100
DM-10102
VL3 with door interlock VL4 adaptor board with door interlock
VL3 without door interlock
VL4 adaptor board without door interlock

Page 10 • DRI-STEEM Vapor-logic3 to Vapor-logic4 Adaptor Board Installation Manual
Removing Vapor-logic3, installing Vapor-logic4
1. Access humidifier subpanel as follows:
• Vaporstream and CRUV: Open control cabinet door by
loosening the screws on the two door latches.
• Vapormist and Humidi-tech: Remove plastic shroud by
unscrewing four Phillips screws (Figure 10-1) securing shroud
to frame (save and re-use screws). Remove galvanized subpanel
cover by unscrewing two Phillips screws securing cover to
subpanel (save and re-use screws).
2. Disconnect Vapor-logic3 keypad/display cable and ribbon cables
from Vapor-logic3 main board and expansion boards, if any.
Ribbon cables will not be re-used.
3. Torque all terminal block screws to 2.5 in-lb (0.28 N·m) to prevent
wires from pulling loose in Step 5.
4. Mark location of Vapor-logic3 main board on subpanel by making
corner marks on subpanel with felt-tipped marker.
5. Use pliers to pull terminal blocks from Vapor-logic3 main board.
Unscrew stand-offs, and remove board and stand-offs (they will not
be re-used).
6. Leaving adhesive backing paper on the six nylon stand-offs
packaged with Vapor-logic4 adaptor board, push stand-offs into
adaptor board mounting holes, as shown in Figure 10-2.
7. Plug Vapor-logic4 keypad/display cable into Display connection
on Vapor-logic4 adaptor board (see Figure 11-1). If present,
plug laptop or network cable into Ethernet connection on adaptor
board.
8. If upgrading to Vapor-logic4 without LonTalk® interoperability
(see Figure 11-2), skip this Step. If upgrading to Vapor-logic4
with LonTalk interoperability, disconnect wires from Vapor-logic3
LonTalk pins and land them as instructed in Table 10-1.
WARNING
Shut down humidifier
Before performing any maintenance or
service procedures, shut off all electrical
power to humidifier using field-installed
fused disconnect, and lock all power
disconnect switches in OFF position.
Electric humidifiers:
Board removal and replacement
Figure 10-2:
VL4 adaptor board stand-offs
Bottom of VL4 adaptor board shown
Stand-off
Table 10-1
Landing LonTalk wires
Disconnect wire from this
Vapor-logic3 board LonTalk pin
Connect it to this pin on Vapor-logic4
adaptor board LON ProtoCessor Module
Ground Ground pin P1-2, P2-4, P4-3, P6-3, or P19-3
AP21A
BP21B
Figure 10-1:
Vapormist / Humidi-tech cover
enclosure screw cap detail
OM-778-3

DRI-STEEM Vapor-logic3 to Vapor-logic4 Adaptor Board Installation Manual • Page 11
Electric humidifiers:
Board removal and replacement
Figure 11-2:
Determining LonTalk interoperability
Corner of VL3 main board shown
VL3 board LonTalk connections (if no wires, then no LonTalk)
Figure 11-1:
Vapor-logic boards
20191817 24232221
7 8 9 101 2 3
16151411 12 13
GTS EXPANSION BOARD 1
GTS EXPANSION BOARD 2
P1P2P3P4P5P6P7P8
P19P18P17P16P15P14P13P12P11
65 87 109 1211 1413 15 1918 20 2321 22 2624 25 2927 28
GTS
31 303233
65
VLC EXPANSION
LON ProtoCessor Module
T2 T1 T1T2T2 3435
1 2 43
7 8 9 101 2 3
20191817 24232221
P21A
P21B
34
VLC
6 5 124 3
T1
1 2 43 65 87 109 1211 1413 15 1918 20 2321 22 2624 25 2927 281716
31 3034 323335
AB
EXPANSION
T2 T1 T1T2T2
VL3
keypad
LonTalk ®
network
LonTalk
®
VL3 main board
VL4 adaptor board (two stacked boards; top board shown)
Laptop or network connection
(Ethernet connection on bottom board)
VL4 keypad connection
(Display connection on bottom board)
The Vapor-logic4 adapter board pin descriptions
are listed in Table 20-1 on the back cover.

Page 12 • DRI-STEEM Vapor-logic3 to Vapor-logic4 Adaptor Board Installation Manual
Figure 12-1:
Splitting interlocked terminal blocks
9. Make sure subpanel surface is clean and dry. Remove adhesive
backing paper from new stand-offs, and press adaptor board into
exact location where Vapor-logic3 board was mounted.
10. Land loose Vapor-logic3 terminal blocks on corresponding pin
locations of Vapor-logic4 adaptor board.
Notes: Some 4-pin terminal blocks are two interlocked 2-pin
blocks that will need to be split. See Figure 12-1.
Scrape away any pin hole or screw corrosion before landing
terminal blocks on Vapor-logic4 adapter board.
Not all Vapor-logic3 wire connections will be used for this
upgrade. Cap bare ends of unused wires with wire nuts,
and tuck them into wire channel.
11. Cut an 18-gauge, stranded wire long enough to reach terminals T2
and 33 on Vapor-logic4 adaptor board (Figure 12-2). Strip ends of
wire, land ends at terminals T2 and 33, and torque terminal screws
to 2.5 in-lb (0.28 N·m).
12. Configure either modulating or on-off duct high limit:
• Modulating: Move Vapor-logic3 terminal block 24/25/26 to Pins
24/25/26 on Vapor-logic4 adapter board.
• On-off: Move wire from Vapor-logic3 Pin 26 to Pin 24 of same
terminal block. Then move terminal block to Pins 24/25/26 on
Vapor-logic4 adapter board.
Transferring expansion board terminal blocks
(Vaporstream only)
Some Vaporstream humidifiers have a Vapor-logic3 expansion board.
Vapor-logic4 adaptor board pin locations for Vapor-logic3 expansion
board terminal blocks are labeled  , as shown in
Figure 11-1.
Leave the wires in the terminals when transferring the terminal blocks
from the Vapor-logic3 expansion board to the Vapor-logic4 adaptor
board.
Note: To facilitate wire re-routing and provide slack, unbundle wires
as necessary.
Figure 12-2:
Jumpering terminals T2 and 33
Jumper
T2 33
Top edge of VL4
adaptor board
Electric humidifiers:
Board removal and replacement

DRI-STEEM Vapor-logic3 to Vapor-logic4 Adaptor Board Installation Manual • Page 13
Electric humidifiers:
Keypad/display removal and
replacement
The Vapor-logic3 keypad/display will not be re-used after this upgrade.
Vaporstream and CRUV with mounted keypad/display
1. Push keypad/display straight up to disengage its mounting keyhole
slots, and pull it off of mounting plate.
2. Disconnect cable from the Vapor-logic3 keypad/display.
3. Plug cable into new Vapor-logic4 keypad/display, and mount new
keypad/display.
4. Close and tightly secure control cabinet door.
Vaporstream and CRUV with unmounted keypad/display
1. Disconnect cable from Vapor-logic3 keypad/display.
2. Plug the cable into new Vapor-logic4 keypad/display.
Vapormist and Humidi-tech
1. On backside of subpanel keypad/display mounting location,
disconnect cable from Vapor-logic3 keypad/display.
2. Remove the four Phillips screws securing Vapor-logic3
keypad/display to sub-panel (save screws and re-use), and remove
keypad/display from subpanel.
3. Position new Vapor-logic4 keypad/display on subpanel, and plug
cable through subpanel and into back of keypad/display.
4. Secure keypad/display to subpanel using screws from Step 2.

Page 14 • DRI-STEEM Vapor-logic3 to Vapor-logic4 Adaptor Board Installation Manual
Electric humidifiers:
Safety circuit wiring
Figure 14-1:
Leaving safety circuit wired in series with one alarm
• CRUV without door interlock,
• Vapormist
• Humidi-tech
The following procedure leaves the safety circuit (door interlock and
low water) wired in series with one alarm:
1. Verify that jumpers shown in Figure 14-1 are in place.
2. Land wire 802 at terminal P3-3 on Vapor-logic4 adaptor board (see
Figure 14-1).
3. Humidi-tech only: Clamp ferrite core around drain valve wiring.
Proceed to “Start-up and validation” on Page 19.
Gray-handled jumper provided with
upgrade kit
DM-11260
DM-11261
Gray-handled jumper provided with
upgrade kit
VL3 main board
VL4 adaptor board
VL4 adaptor board

DRI-STEEM Vapor-logic3 to Vapor-logic4 Adaptor Board Installation Manual • Page 15
Electric humidifiers:
Safety circuit wiring
Figure 15-2:
Vaporstream or CRUV with door interlock; Vaporstream with door interlock and/or cover interlock
• CRUV with door interlock
• Vaporstream with door interlock
• Vaporstream with door interlock and/or cover interlock
The following procedure leaves the safety circuit (door interlock and
low water) wired in series with one alarm:
1. Make sure gray-handled jumper supplied with upgrade kit is
inserted into terminals P3-3 and P3-4 on Vapor-logic4 adaptor
board (Figure 15-1).
2. Vaporstream only: Locate wire 801 that runs to expansion board
terminal T1 (Figure 15-2), and land it at terminal P3-3 on
Vapor-logic4 adaptor board. If wire 801 does not reach P3-3, use
a longer 18-gauge, stranded wire. Torque terminal block screws to
2.5 in-lb (0.28 N·m)
Proceed to “Start-up and validation” on Page 19.
VL3 main board VL3 expansion board (Vaporstream only)
VL4 adaptor board VL4 adaptor board
DM-11262
DM-11259
24 VAC
801 h
T1
24 VAC
801
LW
P3
P3-3
P3-4
FPsw
h
Gray-handled
jumper provided
with upgrade kit
Figure 15-1:
Leaving safety circuit wired in series
with one alarm
DM-10097
DM-10098
VL3 expansion board (Vaporstream only)
VL4 adaptor board

Page 16 • DRI-STEEM Vapor-logic3 to Vapor-logic4 Adaptor Board Installation Manual
1. Access Vapor-logic3 board by loosening screws on the two door
latches removing control cabinet door.
2. Disconnect Vapor-logic3 keypad/display cable from Vapor-logic3
main board.
3. Torque all terminal block screws to 2.5 in-lb (0.28 N·m) to prevent
wires from pulling loose in Step 5.
4. Mark location of Vapor-logic3 main board on subpanel by making
corner marks on subpanel with felt-tipped marker.
5. Use pliers to pull terminal blocks from Vapor-logic3 main board.
Unscrew stand-offs, and remove board and stand-offs (they will not
be re-used).
6. Leaving adhesive backing paper on the six nylon stand-offs
packaged with Vapor-logic4 adaptor board, push stand-offs into
adaptor board mounting holes, as shown in Figure 16-1.
7. Plug Vapor-logic4 keypad/display cable into Display connection
on Vapor-logic4 adaptor board (see Figure 17-1). If present,
plug laptop or network cable into Ethernet connection on adaptor
board.
8. If upgrading to Vapor-logic4 without LonTalk® interoperability
(see Figure 16-2), skip this Step. If upgrading to Vapor-logic4
with LonTalk interoperability, disconnect wires from Vapor-logic3
LonTalk pins and land them as instructed in Table 16-1.
9. Make sure subpanel surface is clean and dry. Remove adhesive
backing paper from new stand-offs, and press adaptor board into
exact location where Vapor-logic3 board was mounted.
10. Land loose Vapor-logic3 terminal blocks on corresponding pin
locations of Vapor-logic4 adaptor board.
Notes: Some 4-pin terminal blocks are two interlocked 2-pin
blocks that will need to be split. See Figure 16-3.
Scrape away any pin hole or screw corrosion before landing
terminal blocks on Vapor-logic4 adapter board.
Not all Vapor-logic3 wire connections will be used for this
upgrade. Cap bare ends of unused wires with wire nuts,
and tuck them into wire channel.
WARNING
Shut down humidifier
Before performing any maintenance or
service procedures, shut off all electrical
power to humidifier using field-installed
fused disconnect, lock all power
disconnect switches in OFF position.
STS humidifiers:
Board removal and replacement
Figure 16-1:
VL4 adaptor board stand-offs
Bottom of VL4 adaptor board shown
Stand-off
Table 16-1
Landing LonTalk wires
Disconnect wire from this
Vapor-logic3 board LonTalk pin
Connect it to this pin on Vapor-logic4
adaptor board LON ProtoCessor Module
Ground Ground pin P1-2, P2-4, P4-3, P6-3, or P19-3
AP21A
BP21B
Figure 16-2:
Determining LonTalk interoperability
Corner of VL3 main board shown
VL3 board LonTalk connections
(if no wires, then no LonTalk)
Figure 16-3:
Splitting interlocked terminal blocks

DRI-STEEM Vapor-logic3 to Vapor-logic4 Adaptor Board Installation Manual • Page 17
STS humidifiers:
Board removal and replacement
Figure 17-1:
Vapor-logic boards
20191817 24232221
7 8 9 101 2 3
16151411 12 13
GTS EXPANSION BOARD 1
GTS EXPANSION BOARD 2
P1P2P3P4P5P6P7P8
P19P18P17P16P15P14P13P12P11
65 87 109 1211 1413 15 1918 20 2321 22 2624 25 2927 28
GTS
31 303233
65
VLC EXPANSION
LON ProtoCessor Module
T2 T1 T1T2T2 3435
1 2 43
7 8 9 101 2 3
20191817 24232221
P21A
P21B
34
VLC
6 5 124 3
T1
1 2 43 65 87 109 1211 1413 15 1918 20 2321 22 2624 25 2927 281716
31 3034 323335
AB
EXPANSION
T2 T1 T1T2T2
VL3
keypad
LonTalk ®
network
LonTalk
®
VL3 main board
VL4 adaptor board (two stacked boards; top board shown)
11. Cut an 18-gauge, stranded wire long enough to reach terminals
T2 and 33 on Vapor-logic4 adaptor board (Figure 17-2). Strip
ends of wire, land ends at terminals T2 and 33, and torque terminal
screws to 2.5 in-lb (0.28 N·m).
12. Configure either modulating or on-off duct high limit:
• Modulating: Move Vapor-logic3 terminal block 24/25/26 to Pins
24/25/26 on Vapor-logic4 adapter board.
• On-off: Move wire from Vapor-logic3 Pin 26 to Pin 24 of same
terminal block. Then move terminal block to Pins 24/25/26 on
Vapor-logic4 adapter board.
Laptop or network connection
(Ethernet connection on bottom board)
VL4 keypad connection
(Display connection on bottom board)
The Vapor-logic4 adapter board pin descriptions
are listed in Table 20-1 on the back cover.
Figure 17-2:
Jumpering terminals T2 and 33
Jumper
T2 33
Top edge of VL4
adaptor board

Page 18 • DRI-STEEM Vapor-logic3 to Vapor-logic4 Adaptor Board Installation Manual
STS humidifiers
Keypad/display removal and replacement
The Vapor-logic3 keypad/display will not be re-used after this upgrade.
STS with mounted keypad/display
1. Push keypad/display straight up to disengage its mounting keyhole
slots, and pull it off of mounting plate.
2. Disconnect cable from the Vapor-logic3 keypad/display.
3. Plug cable into new Vapor-logic4 keypad/display, and mount new
keypad/display.
4. Close and tightly secure control cabinet door.
STS with unmounted keypad/display
1. Disconnect cable from Vapor-logic3 keypad/display.
2. Plug the cable into new Vapor-logic4 keypad/display.
Safety circuit wiring
The following procedure leaves the safety circuit (door interlock) wired
in series with one alarm See Figure 18-1.
1. Locate wire 801, and land it at terminal P4-1 on Vapor-logic4
adaptor board. If wire 801 does not reach P4-1, use a longer
18-gauge, stranded wire.
2. Torque terminal block screws to 2.5 in-lb (0.28 N·m).
Proceed to “Start-up and validation” on Page 19.
801
P4
1
24 VAC
h
l s w
4 3 2
TTA12
Figure 18-1:
Leaving safety circuit wired in series
with one alarm
P4-1
VL4 adaptor board