Starting The Water Heater; Introduction; Starting The Appliance; The Appliance's Heating Cycle - Lochinvar CHA 100 G CE Installation, Commissioning, User & Maintenance Instructions

gis
9
9.1

Introduction

Topics covered in this chapter, in sequence:
• Starting the appliance.
• The appliance's heating
9.2

Starting the appliance

Start the water heater as follows:
1. Fill the water heater (5
2. Open (3.5 "Installation diagram")
valve.
3. Switch on the power to the water heater using the
isolator between the water heater and the power
supply.
4. Use the ON/OFF switch on the control panel to put
the appliance in 'ON' mode (position 'I') or the
weekly program mode (position 'II'); see paragraph
6.2 'Operating modes'.
5. Set the desired water temperature using the
control thermostat (7.5 "Control
If there is a heat demand, the appliance will run
through the heating cycle (9.3 "The appliance's
heating cycle").
9.3

The appliance's heating cycle

The appliance's heating cycle is activated when the
measured water temperature (T
threshold value (T ). This threshold value depends
set
on the currently selected appliance operating mode. If
the appliance is in the 'OFF' mode (frost protection),
for example, this value is 20°C. If the appliance is in
the 'ON' mode, this threshold value can be selected,
for example, position 3 (±60°C).
The heating cycle runs successively through the
following states:
1. HEAT DEMAND;
2. WAITING TIME;
3. PRE-GLOW;
4. IGNITION;
5. RUNNING;
6. WAITING TIME.
Instruction manual CHA
Starting the water
heater
cycle.
"Filling").
the manual gas
thermostat").
) falls below the
water
The complete cycle is explained in the example set out
below.
Comment
The appliance runs through an identical cycle
when frost protection is activated.
1. The control thermostat sensor measures the water
temperature. The water temperature falls below
the set temperature of (for example) 60°C, causing
the control thermostat to close. The burner control
now detects a demand and starts the heating
cycle.
2. Following demand, the waiting time starts. This
waiting time ensures that ignition takes place
safely. The waiting time lasts about 15 seconds.
3. Once the waiting time is over (audible 'clicking' of
the relay in the burner control) the pre-glowing of
the hot surface igniter is started
4. After about 12 seconds (pre-)glowing, the gas
control is opened and ignition can take place.
5. After ignition, the flame is detected and the
appliance will be running. This means that actual
heating has started.
6. When the water reaches the set temperature, the
demand ceases. The gas control closes, and the
burner tray is extinguished. A new waiting time
begins, of about 10 seconds.
7. After this waiting time, the appliance enters an idle
state, and waits until the water temperature again
falls below the set temperature.
With any subsequent heat demand, the heating cycle
will resume from step 1.
49