Vaillant uniSTOR, Руководство по эксплуатации

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Installation and maintenance instructions for uniSTOR 0020111105_00
Fault Cause Remedy
The cylinder cools down at night. One-pipe circulation in the case of
short tube networks with low pressure
loss. Install a non-return valve
(as close as possible to the cylinder).
Primary heating is not working. The gas-
fired wall-hung boiler runs for a short
time, goes off, and then comes back on
again. This is repeated until the cylinder
is at its target temperature. 1. Air in the reheating heat exchanger. Vent the reheating heat exchanger.
2. Heat exchanger surface area too
small. Compare the data provided by the boiler manufac-
turer with the data for the cylinder. It may be possi-
ble to solve the problem by setting a higher flow
temperature on the gas-fired wall-hung boiler.
Only cold or lukewarm water comes out
of the draw-off points. 1. The cold and hot water draw offs on
the cylinder have been mixed up.
Turn off the cold water supply, then let water flow out
via the hot water draw off. Only a few litres of water
flow out if the connection is set up correctly. The hot
water withdrawal pipe intake is then in the air space
and further draining is not possible. If it is possible to
empty the entire cylinder via the hot water draw off,
the connections have been laid incorrectly. Change
the connections!
2. Hot water thermostat mixer set too
low.
Increase the setting.
3. Heating insufficient; gas-fired wall-
hung boiler does not reheat.
External control device faulty.
Air in the reheating
heat exchanger.
Cylinder sensor faulty.
Check whether the gas-fired wall-hung boiler
is working.
Check whether the external control device is working.
Check that the two port valve is in the DHW position.
Replace the two port valve.
Vent the reheating heat exchanger.
Check the thermal cut-out and repair the fault.
Replace the cylinder thermostat.
Water flows out of the expansion relief
valve (only when heating up). Dirt on the valve seat of the expansion
relief valve. Check the seat of the expansion relief valve and
repair the fault.
Pressure reducing valve faulty. Check whether the pressure behind the pressure
reducing valve is lower than 3.0 bar. If so, replace the
pressure reducing valve.
Expansion vessel faulty. Check the pressure in the expansion vessel. If the
pressure is insufficient, re-establish the pressure and
check whether the expansion vessel maintains it.
Expansion relief valve faulty. If the pressure is normal, replace the expansion relief
valve.
Water flows out of the temperature and
pressure relief valve (only when heating
up). Dirt on the valve seat of the tempera-
ture and pressure relief valve. Check the seat of the temperature and pressure relief
valve and repair the fault.
The temperature control system for
the gas-fired wall-hung boiler is faulty. If water is only escaping when being heated up by the
gas-fired wall-hung boiler, check the temperature
control system of the gas-fired wall-hung boiler.
Check whether the two port valve switches to the
heating position when the cylinder temperature is
reached.
Cylinder sensor faulty. Check the cylinder sensor and corresponding thermal
cut-out, replace the cylinder sensor if necessary, and
repair the thermal cut-out fault.
Temperature and pressure relief valve
faulty. If water is only escaping when being heated up by the
electric immersion heater, replace the temperature
and pressure relief valve.
Electric immersion heater faulty. Check the temperature sensor of the electric immer-
sion heater and the corresponding thermal cut-out
and replace the electric immersion heater if neces-
sary.
Table 8.1 Troubleshooting
8 Fault finding