Page 31
ENGLISH
Zodiac
®
JXi
™
Gas-Fired Pool & Spa Heater
|
Installation & Operation Manual
Section 9. Maintenance
If the heater is not going to be used for an extended
period of time and in colder climates, shut it down
completely. See
Section 8.7 and Figure 16
.
IMPORTANT MAINTENANCE NOTE
We recommend that before each pool season, the Thermal
Regulator Valve (TRV) be inspected for proper operation
and replaced if there are signs of scaling or corrosion.
Corrosion and scaling are the result of improperly
balanced water please see
Section
9.1.1
for complete
details on managing your water chemistry.
The TRV ensures the heater operates at it’s optimal
efficiency and if properly maintained will extend the life
of the heater.
WARNING
Do not operate the heater if the water temperature is below 4°C (40 °F).
9.1
Water Chemistry
Proper Water Balance is the key to the enjoyment of your
pool or spa experience and to the long life of your heater.
The pH of your pool or spa’s water is one of the factors
that has the most impact on indicating how properly
balanced the water is. The other factors are: temperature,
total alkalinity, calcium hardness and total dissolved
solids. Cold water is typically more acidic (corrosive),
while hot water tends to lead to a scale forming (basic)
condition. While the heater is in operation, if the PH is
allowed to rise above 7.8 and the calcium hardness and
total alkalinity are not properly maintained; calcium in
the water could lose solubility, coating the copper tubes
inside the heat exchanger. This will restrict the flow of
water resulting in reduced efficiency and possible damage
to the heater.
If the pH is allowed to drop below 7.2, and the alkalinity
is not properly maintained, the water will become more
acidic. Acidic water has a tendency to dissolve metal
components in the pool plumbing such as copper tubing
in the heat exchanger.
9.1.1
Saturation Index
PH, Total Alkalinity (TA), temperature, Calcium
Hardness and Total Dissolved Solids (TDS) play a role in
whether the water is either corrosive or scale forming.
These factors are combined in the Langelier Saturation
Index, which is a method for determining whether or not
water is properly balanced. See
Table 5
below.
Saturation Index = pH + AF + CF + TF -12.1*
A-Factor=(AF), C-Factor=(CF), T-Factor=(TF)
Total Alkalinity Calcium Hardness Temperature
A-Factor
C-Factor
T-Factor
PPM
Factor
Value
PPM
Factor
Value
°C
Factor
Value
5
=
0.7
5
=
0.9
0
=
0.0
25
=
1.4
25
=
1.0
3
=
0.1
50
=
1.7
50
=
1.3
8
=
0.2
75
=
1.9
75
=
1.5
12
=
0.3
100
=
2.0
100
=
1.6
16
=
0.4
150
=
2.2
150
=
1.8
19
=
0.5
200
=
2.3
200
=
1.9
24
=
0.6
300
=
2.5
300
=
2.1
29
=
0.7
400
=
2.6
400
=
2.2
34
=
0.8
800
=
2.9
800
=
2.5
41
=
0.9
A saturation index of 0 is perfectly balanced
A negative saturation index has corrosive tendencies
A positive saturation index has scaling tendencies
A saturation index of +0.3 or -0.3 is ideal
*-12.1 should be changed to -12.2 if Total Dissolved Solids (TDS)
measure at 1,000 ppm or greater
Table 5.
Water Saturation Index
The practice of putting tablet-based sanitizer in the
skimmer basket can produce heavily chlorinated water
with very low pH. If this comes in contact with metal
parts of the heater it can cause serious damage. Practices
like this should be discontinued.
If acidic conditions are present, there could be signs of
metal in the pool water that could cause staining on the
floor of your pool. This might manifest itself in the form
of brown stains on the finish of your pool bottom or pool
water discoloration. Your local pool dealer can test for
metals in your water or can provide you with a test kit.
Every effort should be made to maintain the water
balance of your pool or spa in the proper range. Ignoring
this very important component of your pool’s water
chemistry can make the water less enjoyable to bathe in
and result in permanent damage to your heater and/or
complete failure of individual components.
Zodiac Group Australia Pty, Ltd. does not warrant heat
exchangers damaged by corrosive water issues or from
the build-up of calcium in the heater’s heat exchanger.
Any questions regarding proper water balance can be
directed to our product support line at Zodiac
®
or to your
local pool dealer.
NOTE:
The Thermal Regulator Valve (TRV) is an indicator of how
well the water balance is being maintained. The TRV should be in-
spected before each pool season to ensure it is clean and operating
properly. If you see signs of calcium buildup (scale-forming or base
water) or corrosion (acidic water) the TRV should be replaced and
your water balanced.
