Ariston CLAS X User Manual

Training manual CLAS X
Pag. 14 di 69
The pump has 2 speeds that are operated by
the control of the heating delivery-return ΔT. It
is operated as follows:
 ΔT del-ret < ΔT – 2°C → V2 pump speed
 Δt del- ret > ΔT → V3 pump speed
where: ΔT= 20°C (default value can be
sent by parameter 239 between 10 and
30°C).
Speed switching is carried out with a 5 minute
delay (non-settable value) raising or
diminishing.
PUMP
Speed control
Performed from the flow and return NTC. If
the temperature rise 102°C a lock out occurs,
indicated on the display with 1 01.
Overheat control
NORMAL BOILER OPERATION
After flame detection the boiler is free to
modulate the power according to the required
thermal load. Modulation is carried out
between the maximum heating power values
(adjustable from the control panel with
parameter 231) and the minimum power
value (set made on the gas valve). The shut
down temperature of the burner is operated
as follows:
 1° min after flame detection:
T off = T set-point + 8°C
 2° min after flame detection:
T off = T set-point + 6°C
 starting from the 3
rd
min after flame
detection:
T off = T set-point + 4°C
This logic is used to prevent the burner from
shutting down too quickly with the system at
temperature.
Next ignition can be delayed from 0 to 7
minutes (default value = 2 min., adjustable
from the control panel with parameter 236)
FLAME
MODULATION
N.B. Starting from heating request, the “limit temperature” (88°C, not adjustable fixed
value) remains on executed by the primary exchanger outlet probe (NTC 1).
If there is a bad circulation through the heating system, the automatic by-pass can be
opened (max capacity 350 l/h).

Ariston CLAS X Specifications

General

Brand	Ariston
Model	CLAS X
Category	Boiler
Language	English