Glow-worm Clearly Solar System Hydraulics - Manual (Page 23)

23
8 Fault Finding
Malfunction Cause Remedy
The pressure gauge indicates a drop in
pressure.
A drop in pressure is normal shortly
after filling the system, since air still
escapes from the system. If a pressure
drop occurs again later on, the cause
may be an air bubble, which has been
subsequently released.Furthermore there
are fluctuations to the pressure in normal
operation mode between 0.2 to 0.3 bar,
depending on the system temperature. If
the pressure drops continuously, there is
a leak in the solar circuit, in particular in
the collector array.
First check all screw connections, stuffing
boxes at gate valves and threaded
connections, then the soldering points.
Check the collector array and replace a
tube or the collector if necessary.
The water pressure and amount of
discharged water decreases at hot water
taps.
Pressure in the main cold water supply
too low.
Inform the user and notify the water
supply company.
Line strainer in the pressure limiting valve
dirty.
Clean the line strainer in the pressure
limiting valve and replace it if necessary.
Pressure limiting valve defective. Replace the pressure limiting valve.
Blockage in the system. Unblock the blockage and replace any
blocked parts.
Check the system for water leaks at the
expansion relief valve and temperature /
pressure limiting valve.
The system is making noises. Normal in
the first few days after filling the system.
If it occurs later, there are two possible
causes:
1. The system pressure is too low. The
pump is drawing air via the bleeder.
Increase the system pressure.
2. Pump power set too high. Switch to a lower speed.
The solar gain is unusually low. The pipe insulation is too thin or incorrect.
The system may have been designed
incorrectly.
Check the insulation. Check the layout
of the system (collector size, shading,
pipe lengths) and modify the system if
necessary.
Solar control
Display example “NTCA Err“ or similar
(reference system wiring instructions
including Fluropro solar controller)
Defective sensor (short circuit or
interruption).
1. Check the cable connection.
2. Measure the resistance values of
the disconnected sensor at known
temperatures, and compare these with
the manufacturer's specifications.
3. Inspect the piping for damage.
Solar cylinder
The cylinder cools down at night. The
flow and return temperatures vary after
switching off the pump. The collector
temperature is higher than the air
temperature at night.
1. The gravity brake is blocked. 1. Check the position of the blue handle.
2. Check the gravity brake for tightness
(jammed cuttings, particles of dirt in the
sealing face).
3. Do not connect the solar heat
exchanger directly, rather pull the supply
pipes downwards and then upwards to
the collector (syphon supports the gravity
brake) or install a 2-port valve, which
is switched on at the same time as the
pump.
2. One-pipe circulation in the event of
short pipe networks with low pressure
loss.
Install a gravity brake (as close as
possible to the cylinder).
Reheating is not working. The boiler
runs for a short time, goes off and then
back on again. This is repeated until the
cylinder is at its target temperature.
1. Air in the reheating heat exchanger. Bleed the reheating heat exchanger.
2. Heat exchanger surface area too small. Compare the specifications of the boiler
manufacturer with those of the cylinder
manufacturer. The problem may be able
to be solved by a higher setting of the
flow temperature at the boiler.
Table 8.1 Fault Finding (continued)