43
3.32 - Checking
and adjusting the
gas pressure at
the burner
The gas pressure of the burner must
match the values given in the table in
chapter 8. The heater operates
between two power levels, and
therefore there are 2 values of burner
pressure that must be checked, one
for the maximum input rate and one
for the minimum input rate.
To check the pressure proceed as
follows:
remove the heater cover panels
remove the screw from the
pressure probe “-” (minus) on elbow
“C”, see figure 44;
remove the silicone tube from the
pressure coupling “+” (plus) on
elbow “C”, see figure 44;
connect a pressure gauge with a
resolution of at least 0.05 in.W.C.
(0.1 mbar), making a T connection
as shown in figure 43;
be sure to maintain the correct
polarities between the
connections;
turn on the heater, keeping
selector “4” in position “C” (see
figure 48) and compare the
measured value with that given in
table 8.1 under the heading
“(Natural or LP) gas maximum
burner pressure”;
with the heater at a temperature
higher than 140°F (60°C), rotate
selector “4” to position “D” (see
figure 48) and compare the
measured value with that given in
table 8.1 under the heading
“(Natural or LP) gas minimum
burner pressure”.
If the above values do not match
those given in table 8.1, it is
necessary to operate as follows to
adjust the pressure.
use regulator “A” (see figure 45) to
adjust the maximum pressure with
selector “4” in position “C” (see
figure 48);
use regulator “B” (see figure 45) to
adjust the minimum pressure; Be
sure that the heater is at a
temperature higher than 140°F
(60°C), selector “4” is in position
“D” and that “C” lamp is lit (see
figure 48)
After making any adjustments,
reassemble the unit, being careful to
seal the regulators “A” and “B” (see
figure 45) with a drop of red paint or
similar method.
3.33 - Check CO2
level
During normal operation at altitudes
below 2000 ft (659 m), the CO2
(carbon dioxide) content of the
heater flue gases is given in table
8.1 at the end of the manual. A
different value from that shown may
result in a malfunction. To check
this value it is necessary to
analyze the exaust fumes using a
combustion analyzer; proceed as
follows:
connect a combustion analyzer
to the special coupling on the
flue gas discharge fitting;
rotate selector “4” (see figure 48)
to the “B” position (sanitary hot
water);
open the hot water valve until the
temperature inside the water
heater reaches and maintains
temerature at approximately
160±10°F (70 ± 5°C)
compare the measured value
with that shown in chapter 8
“CO2 content”
3 - INSTALLATION