Installation Manual
Floor standing storage boiler – Cod. 99949NA – November 2002
16
BOILER MAINTENANCE
(carried out by qualified heating engineers)
Every 12 months, or more frequently if the quality and consumption of water demand it, check
the condition of the magnesium anode and replace it if signs of wear are evident. To check the
condition of the anode 3 (see fig.1), open valve 4 on the top of the boiler, undoing the red knob
in a clockwise direction. If water seeps out of the valve this means the anode is worn and must
be replaced. If on the other hand there is no evidence of water leaking out, the anode can still
be used. After carrying out the operation described here, remember to tighten the valve once
more.
If the water pressure exceeds 6 bar, fit a 2 lt expansion tank to the boiler, proceeding as
follows (see fig.1)
If the water pressure exceeds 6 bar, fit (for the 45 lt. cylinder model)
a 2 lt. expansion tank to the cylinder proceeding as follows (see fig.
2)
a. close the water supply
b. fit the ½” tee (no.1) onto the hot water outlet connection with a
½” flexible pipe, connect the “tee” to the d.h.w. circuit expansion
tank (no.3)
c. open the water supply
LIMITER
The boiler is equipped with a variable flow limiter at the cold water
inlet. The flow limiter can be adjusted by turning the screw (see fig.3
pos.C) in order to obtain the correct flow rate of domestic hot water
for the specific boiler output.
FLOWSWITCH
This device gives precedence to domestic hot water and is fitted to
boilers which supply instantaneous hot water (see fig. 2, item B fig.
3). It allows conversion to hot water even with a minimum hot water
demand (2 litres/min.), using an electromagnetic principle with
electrical switching by means of a relay. The device is made of non-
toxic, corrosion-proof ZYTEL 101 L plastic material which has type
approval with non-toxic characteristics and is unaffected by hard
water. In addition, a filter is fitted before the flowswitch and at the cold water inlet which
eliminates any water impurities. These features guarantee that the flowswitch operation is
highly efficient.
BY-PASS
All boilers are fitted with a by-pass. This element is essential in the following
cases:
if a two-way zone valve is installed
if thermostat valves are installed in the radiators.
To adjust the by-pass proceed as follows (see fig. 3 pos.A): fit the screwdriver
to the plastic screw of the by-pass, bearing in mind that when the slot of the
screw is horizontal the by-pass is totally open, allowing all the water to pass,
while when it is vertical the by-pass is totally closed. For partial by-pass flows,
use the adjuster screw.
D.H.W. CIRCULATING LOOP
It is possible to make a d.h.water circulating loop by fitting the circulating loop
pipe to the loop connection at the top of the 45 lt. cylinder or on the back side
for the 100 lt. cylinder.
Fig. 4
Flussostato
Fig. 3
FREDDA
CALDA
CALDA
VISTA LATERALE
VISTA DALL'ALTO
3
2
1
GAS
ANDATA
RITORNO
ALL'IMPIANTO
1
3
2
Fig. 2
Fig. 1
