6 720 816 815 (2016/10)
Greentherm 9800 SE 160/199 | SEC 199
Troubleshooting | 51
8.9
Adjusting Gas/Air flow
The CO2 can only be adjusted by a certified gas technician
with a calibrated CO2 analyzer.
The P1 minimum operating gas pressure is 3.5" WC for Natural
Gas and 8" WC for Propane. Do not proceed in adjusting CO
2
until pressure is at or above these levels, but not to exceed
10.5" WC for Natural Gas and 13" WC for Propane.
8.9.1 Access to CO
2
measuring port
▶ Open a hot water tap and let the appliance work for 2 or 5
minutes.
▶ Remove the screw from the flue adaptor on the left side of
the appliance, as seen in fig. 48.
▶ Insert CO
2
analyzer probe into the measuring port. The tip
of the probe should be in the center of the flue pipe (approx
1.5" inserted). Avoid air gaps between probe and
measuring port as they can alter readings.
Fig. 48
C0
2
measuring port
8.9.2 Adjusting the maximum flow (Parameter P1)
▶ Access to menu
P1
.
▶ Open all hot water taps to achieve a flow rate of at least 6
gallons per minute. (1 tub and 2 sinks should be sufficient).
If heater goes back to P2, open more hot water fixtures to
allow sufficient flow and access to P1 menu.
▶ Touch symbols
or
to select
U1 - L1 Auto Adjust
.
NOTICE:
▶ Before adjusting Gas/Air flow, turn off
any backup appliance (example; solar)
to avoid high inlet water temperature.
Appliance is pre-adjusted by default with
factory parameters, gas/air adjustment is
required in Natural Gas installations where
energy content is less than 900 BTU/cu ft,
and in installations with repeated
unresolved errors (ref. to chapter 9).
Adjustment may be required when
converting to LP. In these situations, a CO
2
analyzer can be used to assure a more
accurate air adjustment.
CAUTION:
▶ One factor that may affect CO
2
levels is
improper gas pressure. Please see
Chapter 4.13 for the procedure to
measure gas pressure and record your
findings.
Only possible after access
Authentication
menu (
section 6.6).
Always start the adjustments by
U1 (L1)
and
P1 (A1)
followed by
U2 (L2)
and
P2 (A2)
.
Allow the appliance to stabilize before
performing CO2 and CO readings.
Let appliance warm up and wait for 2 or 5
minutes for each CO2 and CO readings.
This will avoid wrong CO2 and CO read-
ings.
It’s recommended to use CO
2
analyzer to
perform appliance adjustment in case of gas
conversion or abnormal combustion noise.
