15
16. TROUBLESHOOTING
Table 3
No.
Problem
Possible cause
Repair
1
Water pressure in the
system dropping slowly.
Installation is not
sealed.
Check whether all welded connections, threaded
connections, unions etc. are sealed.
2
Radiators are cold at
system’s maximum
height and a low sound
is heard.
Air in the system and
small pressure in the
system.
Increase system pressure and bleed the air from the
system and radiators.
3
Radiators are not heated
along their entire length.
Air in the radiators.
Bleed the air from the radiators using release valve.
4
Safety valve is not
discharging water from
the system and the
pressure is below 3
(2.5) bar.
Faulty safety valve.
Replace safety valve.
5
Pressure in the system is
over 3 (2.5) bar and
safety valve is not
discharging water from
the system.
Faulty safety valve.
Replace safety valve.
6
Sudden water
temperature rise in the
system.
Air in the system.
Bleed the air from the radiators.
Valves toward radiators
are shut.
Open all valves in the heating system and enable
normal water circulation in the system.
Circulation pump
failure.
Repair or replace the circulation pump to enable
heating system operation.
Power outage.
Open all valves that reduced the heating system and
first of all, the by-pass valve.
Stop making fire or make less fire and carefully
monitor the system so that the water temperature does
not exceed 90
°
C when the power is back on.
7
Sudden water pressure
rise in the system due to
water temperature
increase.
Reduced expansion
vessel pressure or
vessel is completely
empty. Remove the
vessel’s lid or valve
head and bleed some
air through the valve. If
the membrane is
destroyed, water will
leak from the valve and
if only half-empty, only
air will come out.
If water is leaking from the valve, replace expansion
vessel.
Of only air is coming out from the valve, remove the
vessel from the system and apply additional pumping.
Vessel pressure should be equal to or higher than the
height difference between the highest and lowest point
of the system. Example:
For a 5 m height difference, the pressure equals
Pmin
≥
0.5 bar.
Air in the system.
Release air from the system.
