Installation, Start-Up, Adjustment and Maintenance Manual
5
2. OVERVIEW AND TECHNICAL DATA
2.1 OVERVIEW
The High Efficiency Chillers ACF60-00 series are water chillers, equipped with an air-cooled condenser and
designed for outdoor installation. The absorption cooling cycle is based upon a solution of water and
ammonia for the production of chilled water (temperature of chilled water is given by Technical Tables).
The chilling system is fed by thermal energy provided by a gas burner, therefore the required electric energy
is limited to driving the fan and pump motors (the only mechanical moving components of the unit). The
evacuation of combustion gases occurs by mixing them with condenser air using an axial fan of the
appliance. The combustion fuel is Natural Gas or LPG.
The
STANDARD
and
HT
versions are designed for the commercial and industrial air-conditioning
applications in the hot climate areas.
The
TK
versions are designed for the air-conditioning and refrigeration of technological applications (for
example, in the industrial process, that could require chilled water up to 24h a day).
The
LB
versions are designed for the low temperature refrigeration applications (for example cold rooms for
food conservation).
ACF60-00 HR
, “Heat Recovery”. This is an ACF60-00 with a heat recovery system able to provide 60,500
Btu/hr of nominal cooling capacity when operating without the heat recovery system. With the heat recovery
system, it can obtain a cooling capacity of 61,234 Btu/hr, at the same time providing 86,400 Btu/hr of heating
capacity.
For further information see next paragraph, technical data.
ACF60-00 units are Natural Gas or LPG fired and supplied with 208 - 230V 60Hz single-phase electrical
power.
ACF60-00 units could be controlled by DDC - Direct Digital Controller
(available as Optional). DDC can control up to 16 single chillers.
Figure 1 -
Direct Digital Controller
CHILLER’S CONTROL AND SAFETY DEVICES
Electronic Control Board
with integrated microprocessor controls the operation of the chiller.
High Temperature Limit Switch
(manual reset) is located at the generator wall above the combustion
chamber; the switch opens if the generator's sidewall temperature exceeds 330°F; the switch is manual
reset. The switch can be reset when the generator sidewall temperature drops below 280°F.
Safety Relief Valve
on the sealed circuit.
Differential Air Pressure Switch
on the combustion circuit stops the burner ignition due to insufficient
combustion air flow.
Ignition Control Box
controls the burner ignition. Checks the differential air pressure switch and starts the
pre-mixer blower. After 30 seconds of purging, the ignition control box opens the gas valve and starts the
ignition transformer sparking at the burner for 8 seconds. If no flame is detected, the ignition control box will
close the gas valve and retry lighting after an inter-purge period of 30 seconds. The ignition control box will
try a total of three times to light. The unit will stop if no flame has been established or detected after the 3
tries.
Dual Gas Valve:
two gas valves in the same housing, electrically controlled, which positively stops gas flow
when either closes.