HISEER AS10S/L, Operation Installation Maintenance Manual

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16
Multiple Units in Series Connection
(1)
Heating working principle
To set two or more units in parallel operation, set the primary unit to the required
parameters, other units could have 2~5°C difference of ST01,ST02 and ST05 to allow
for energy stage control.
1. When SF04:ENABLE COMPENSATION=NO:
a). if there is a heating demand, then the unit will start to heat. The unit with the
lower ST02 will stop first, the others will stop if their outlet water temp. B2
continue to rise and reach its pre-set ST02.
b). Inlet water temperature B1 will drop when units stop. The unit with the higher
RTc-ST04 will start first again to heat . If this unit can meet the heating capacity
then its Outlet water temperature B2 will not drop any further, only this unit will
run as required. If the heating load is bigger than the capacity of one unit then the
inlet water temperature B1 will continue to drop to below the second unit
RTc-ST04 , the second unit will be switched on and start increasing the heating
capacity.
2. When SF04:ENABLE COMPENSATION=YES:
ST02 is replaced by “Set temperature at heating” =ST05+ST06 *(ST05-OT).
Refer to chapter “Heating compensation curve setting” .
(2) Hot water production working principle:
On hot water mode, Three way valve (VXV) will open AB-B.
When domestic hot water requirement calls, the three way revert valve ( VXV) will
have the priority to revert to the hot water tank (VVB ). After the domestic hot water
reach its set temperature ST09, the three way revert valve ( VXV) return to heating
circuit position. After hot water temp. B4<ST09 – ST10, three way revert valve (VXV)
will revert to hot water circuit again.
Systems Overview