Haier CA0035EAND Service Manual page 28

■ Type Selection of Auxiliary Electric Heater
According to engineering requirements, it is recommended that one set of auxiliary electric heater be used as
standby system, which is started to keep water temperature of the unit in case of defrosting or temporary fault of
such equipment.
Considerations on type selection of auxiliary electric heater mainly include the minimum average outdoor ambient
temperature in winter and the capacity of standby system. Based upon the local minimum average ambient
temperature in winter and the water outlet temperature of the unit, the unit capacity attenuation Q2 can be
obtained via comparison between the capacity Q1 from the "Performance Correction Curves" and the nominal
capacity Q of the unit.
Q2 = Q - Q1
The capacity of auxiliary electric heater generally selected, W
W = a* Q2 = a*(Q - Q1)
In which, a refers to margin coefficient, taking between 1.0 and 1.5, and it is larger in northern area, e.g.
taking 1.5 in Hubei province and its northern area.
■ In heating mode, the unit capacity may drop with the decreasing ambient temperature, thus users shall add the
auxiliary electric heater at the hot water side for the areas under the low average outdoor ambient temperature
in winter, otherwise the unit performance may be affected.
■ Electrical Connection
1. Connection diagram of the unit power cords
R
S
T
N
Breaker
■ The breaker with sufficient capacity must be arranged at the entry of power cord. Such breaker shall be
protected against short circuit and earth fault, and its contact spacing is at least 3mm.
Please install it by yourself.
CAUTION
Breaker
R S T N R S
Master unit Slave unit 1
CAUTION
Breaker
T N R
26
S T N
Slave unit 15