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CE CES CERO SERIES |
5
possibility of dry firing. Each element circuit is individually fused.
The fuses are located in the fuse box (7).
In order to avoid latent heat buildup, the unit has an electronically
controlled delay timer that delays the activation of the heating ele-
ment slightly. This feature allows air to be purged from the system
before the element arrangement is activated to heat, and eliminates
scalding risk. Beside the electronic delay, the board has no addi-
tional safety functions.
The display monitor shows the set point temperature, the actual
outgoing water temperature, the flow rate and the heating rate. It
is possible to change the units from °F / gpm to °C /l/min.
Safety is provided by a pressure relief valve (8) with a 150 psi setting.
5. Troubleshooting
Before troubleshooting, check the following items:
f
Is the water pressure more than 3 psi (0.21 bar)?
f
Is the electric supply a:
- Wye (4 wires + ground) or
- Delta (three wires + ground)?
f
Does the electric supply match the voltage and configuration
designation shown on the unit nameplate?
f
If the heater fails to maintain the desired temperature, check
the flow rate according to the table See 15.6, “CE/CES/CERO
Temperature rise”, pg. 22.
The following items are required for testing to diagnose a possible
failure:
Continuity tester, 600 V voltage meter, amp and Ohm meter.
Use the following steps for diagnosis:
f
Turn off the power supply to the heater.
Caution
: follow all safety precautions in 2.2, “Safety precau-
tions”, pg. 3.
f
Turn off the heater on/off switch (12).
f
Open the heater enclosure.
f
Check for any loose connections, and properly operating
breakers.
f
Purge the heater to cool down the heater and to reset the elec-
tronic thermostat function.
f
Turn the main breaker back on. Turn on the heater on/off
switch (12). For resistivity test turn the breaker off and check
voltage just in case.
5.1 Fault table
Symptom
Possible cause
Action
No hot water (A)
(B)
(C)
(D)
(E)
(F)
(G)
(H)
(I)
Circuit breakers off
Turn circuit breakers on
On/off switch (12) defect
Check voltage
Pressure switch (3)
Check voltage
PCB sensor
PCB voltage supply
Check sensor NTC and flow
sensor, PCB voltage supply
Transformer
Check voltage X8 primary
Check voltage yellow-white
(secondary)
Safety cut-off
Check voltage
Fuse (7)
Check voltage
Element (1)
Check resistivity
Reduced (J)
hot water
(K)
(L)
Ball valve closed (14, 15)
Open ball valve
Filter clogged
Clean filter
Air in the system
Vent the system
Lukewarm (M)
water (N)
Fuse burned (7)
Check continuity
Triac failure
Check amperage
5.2 Solutions based on symptoms in fault table
Symptom
Analysis
Solution
(A)
(B)
(C)
(D)
(E)
(F)
(G)
(H)
(I)
(M)
(N)
No power
Activate power
No continuity
Replace on/off switch (12)
No continuity
Replace pressure switch (3)
No continuity NTC
No continuity flow sensor
Replace sensor
Replace flow sensor (4)
X8(X10) > 200 V, A1 PWR IN 1-
A1 PWR In 2 > 20 V
Replace transformer (10)
No continuity in cold status
Replace safety cut-off
No continuity
Replace fuse (7)
Resistivity nok
Replace element (1)
No continuity
Replace fuse (7), check re-
sistivity of the associated
element
No ampacity element supply
Replace triac
5.3 Cold element resistivity by heater type (in Ohms)
(kW)
208 V
240 V
400 V y 480 V y
400 V ∆ 480 V ∆ 575 V ∆
12
11.41 Ω
13.55 Ω
12.48 Ω
16.88 Ω
-
-
-
15
8.07 Ω
11.41 Ω
11.41 Ω
13.55 Ω
-
-
-
18
6.93 Ω
9.32 Ω
8.07 Ω
12.48 Ω
-
18.73 Ω
-
24
11.41 Ω
13.55 Ω
13.55 Ω
20.53 Ω
9.32 Ω
13.55 Ω
20.53 Ω
27
9.32 Ω
12.48 Ω
11.41 Ω
16.88 Ω
8.07 Ω
12.48 Ω
-
36
6.93 Ω
9.32 Ω
9.32 Ω
-
6.93 Ω
9.32 Ω
13.55 Ω
48
11.41 Ω
13.55 Ω
-
-
9.32 Ω
13.55 Ω
20.53 Ω
54
9.32 Ω
12.48 Ω
-
-
8.07 Ω
12.48 Ω
-
60
8.07 Ω
11.41 Ω
-
-
6.93 Ω
11.41 Ω
-
72
6.93 Ω
9.32 Ω
-
-
-
9.32 Ω
13.55 Ω
81
-
-
-
-
9.32 Ω
12.48 Ω
-
90
-
-
-
-
8.07 Ω
11.41 Ω
-
108
-
-
-
-
6.93 Ω
9.32 Ω
13.55 Ω
120
-
-
-
-
8.07 Ω
11.41 Ω
-
144
-
-
-
-
6.93 Ω
9.32 Ω
13.55 Ω
Depending on element type, hot resistivity may be 5% more than
cold resistivity.
EN
GL
ISH
OPERATION
TROUBLEShOOTINg