Slant/Fin VHG-100-CH, Installation And Service Manual

Page: 131 / 164

E93.1901EN032 Installation and Service Manual SlantFin VGH-CH / CO
131
CO
2
/ O
2
Adjustment procedures
The adjustment of the low fire screw is much more sensative than the high fire screw. Only make small
adjustments 1/8th of a turn at a time and then wait for the boiler to stabilize and give the combustion analyzer
enough time at least 20 seconds to draw in a stable sample.
Procedure 1: adjust at High Fire
Carry out the following steps:
1. From status screen, press MENU .
2. Press UP/DOWN
↑↓
to select "System Test"
3. Press ENTER to activate the system test.
→ "Test State:
Off"
4. Press ENTER to activate the test state.
→ "Test State:
Off "
5. Press UP/DOWN
↑↓
multiple times to select "High Power"
→ "Test State:
High Power ".
The boiler becomes active; after about 10 seconds the boiler burns at high fire.
If the boiler doesn’t start, first check gas pressure, second open screw 1/2 turn extra - clockwise
Note : once the test state is active, it is not necessary to press a button; selecting the desired power is sufficient.
Wait a minimum of 20 seconds for the boiler to stabilize before taking combustion readings between changes
and adjustments to the combustion.
For your information "Fan speed" and "Ionization" are displayed.
6. Measure the CO
2
percentage at the flue gas test port on the vent connection.
7. By setting screw [2], adjust the gas valve to obtain the CO
2
value of Table 17.1.
8. To return to the status screen, and stop the boiler, press ESCAPE or MENU 3 times, or RESET once.
Increase CO
2
CO
2
↑
[2]
O
2
↓
Turn screw [2] right (clockwise)
Decrease CO
2
CO
2
↓
[2]
O
2
↑
Turn screw [2] left (counterclockwise)
The system test automatically stops after 10 minutes, after this the system continues with normal demand handling.
When the system test mode is changed during an active system test, the 10-minute timer is restarted.
Procedure 2: adjust at Low Fire
Carry out the following steps:
1. Press UP/DOWN
↑↓ multiple times to select "Low Power" → "Test State:
Low Power ".
After about 10 seconds, the boiler burns at low fire.
2. Measure the CO
2
percentage at the flue gas test port on the vent connection.
3. By setting screw [1], adjust the gas valve to obtain the CO
2
value of Table 17.1.
Increase CO
2
CO
2
↑
[1]
O
2
↓
Turn screw [1] right (clockwise)
Decrease CO
2
CO
2
↓
[1]
O
2
↑
Turn screw [1] left (counterclockwise)
4. To return to the status screen, and stop the boiler, press ESCAPE or MENU 3 times, or RESET once.
The system test automatically stops after 10 minutes, after this the system continues with normal demand handling.
When the system test mode is changed during an active system test, the 10-minute timer is reloaded.
Repeat procedures 1 and 2 until measured values match the values from Table 17.1 best.
Venturi adjustement
The venturi is a fixed part and needs no adjustments.