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HENCO Industries NV • Toekomstlaan 27 - B-2200 Herentals • Tel. +32 14 28 56 60 • Fax +32 14 21 87 12 • www.henco.be
9. TROUBLESHOOTING
X. PROBLEM
X.XnoituloSesuacelbissoP
1. THE HEATING CIRCUITS OF THE FLOOR HEATING (FH) ARE NOT HEATED UP
1.1 The temperature limiter (TB) switches off the circulating pump of the
control unit.
Cause: TB is set to a very low value.
Set the TB by approx. 10 K higher than the required flow tempera-
ture for FH.
Take into consideration the max. admissible flow temperature!
Differential gap of the TB: approx. 6 K.
The unit restarts quicker if the TB is removed from the unit for a
short time to allow a faster cooling down to switch-on temperature.
1.2 The TB switches off the circulating pump of the control unit.
Cause: Initially, the circulating pump remains switched on even
when all of the floor heating circuits are blocked. The “idle running”
of the pump without water circulation heats up the water due to
waste heat of the pump motor. On reaching the maximum tempera-
ture, the TB switches off the circulating pump!
Remove the TB from the compact control unit and install it at the
supply line or, eventually, at the return line of the heating circuit
manifold.
Use an electrical connecting box with pump relay (pump logic).
Thanks to the relay, the circulating pump operates only if at least
one heating circuit of FH is opened (requires heat).
1.3 The circulating pump is connected to a room-temperature thermostat
or to an electrical connecting box.
If all the actuators close, the pump is switched off. If the idle period is
longer, the supply water for FH is cooled down. Therefore, the injec-
tion mixing valve opens and hot water is injected from the primary
circuit. As a result, the control unit is heated up. On reaching the
TB’s switch-off temperature, the contact opens. The pump will not
switch on again.
Remove the TB from the compact control unit and install it at the
supply line or, eventually, at the return line of the heating circuit
manifold.
Subsection 1.1 should also be taken into consideration.
2. THE SUPPLY WATER TEMPERATURE CANNOT BE SET TO THE REQUIRED VALUE OR IT FLUCTUATES WITHIN A VERY WIDE
RANGE
2.1 The compact control unit’s supply (inlet) pipe and return (outlet) pipe
are misconnected.
Check all inlets and outlets of the compact control unit for correct
connection. Supply inlets and return outlets are marked with stickers.
Please take into account Fig. 2 and 3.
2.2 The circulating pump’s pressure head/pump stage is set at a very
high value.
Increase the rotation frequency, the pump’s pressure head/pump
stage, respectively.
2.3 The heating load is too big for the control unit used, i.e., the heat
consumption exceeds the rated heat output of the compact control
unit. This state may set in temporarily, e.g., in case of heating a
“cold” floor for the first time.
Check the maximum heat consumption and compare it with the rated
heat output. If necessary, distribute the heating circuits to a second
control unit with a respective manifold.
If the cause is in the initial heating up of a given floor heating sys-
tem, the function may be normalized after the heating up phase. This
is possible chiefly in an operating mode within the top values of the
rated power.
2.4 RevitcefedsidaehcitatsomrehT eplacement of thermostatic head.