Operation; Overview: Operation; Heating; Domestic Hot Water - Daikin CHYHBH05AA Installer's Reference Manual

9 Operation

7 Put the front panel back in its place.
9 Operation
9.1

Overview: Operation

The gas boiler is a modulating, high-efficiency boiler. This means
that the power is adjusted in line with the desired heat requirement.
The aluminium heat exchanger has 2 separate copper circuits. As a
result of the separately constructed circuits for space heating and
domestic hot water, the heating and the hot water supply can
operate independently, but not simultaneously.
The gas boiler has an electronic boiler controller which does the
following when heating or hot water supply is required:
▪ starting the fan,
▪ opening the gas valve,
▪ igniting the burner,
▪ constantly monitoring and controlling the flame.
It is possible to use the boiler's domestic hot water circuit without
connecting and filling the central heating system.
9.2

Heating

Heating is controlled by the indoor unit. The boiler will start-up the
heating process when there is a request from the indoor unit.
9.3

Domestic hot water

Not applicable for Switzerland
Instant domestic hot water is supplied by the boiler. Because
supplying domestic hot water has priority over space heating, the
boiler will switch to domestic hot water mode whenever there is a hot
water demand. When a simultaneous space heating and domestic
hot water demand occurs:
▪ during heat pump only operation (space heating mode), the heat
pump will provide heat while the boiler is bypassed and switches
to domestic hot water mode to provide domestic hot water.
▪ during boiler only operation, and with the boiler in domestic hot
water mode, space heating will NOT be provided, but domestic
hot water will.
▪ during simultaneous heat pump and boiler operation, the heat
pump will provide heat and the boiler will be bypassed and switch
to domestic hot water mode to provide domestic hot water.
This manual only explains the domestic hot water making without
having a domestic hot water tank combined with the system. For the
operation and needed settings of domestic hot water in combination
with a domestic hot water tank needed for Switzerland, please refer
to the manual of the heat pump module.
Installer reference guide
68
9.3.1 Flow resistance graph for appliance
domestic hot water circuit
Not applicable for Switzerland
l/min
15
13
11
9
7
5
3
1
0.2 0.4 0.6 0.8 1.0 1.2
0
The minimum flow for domestic hot water operation is 1.5 l/min. The
minimum pressure is 0.1 bar. A low flow (<5 l/min) can reduce
comfort. Make sure to set the setpoint high enough.
9.4

Operation modes

The following codes on the service display indicate the following
operating modes.
Off
The gas boiler is out of operation but is supplied with electric power.
There will be no response on space heating and/or domestic hot
water demands. Frost protection is active. This means that the
exchanger is heated up if the water temperature in the gas boiler is
too low. If applicable, the keep hot function will also be active.
If frost protection or keep hot function is activated, will be displayed
(heating the exchanger). In this mode, the pressure (bar) in the
space heating installation can be read on the main display.
Waiting mode (blank service display)
The LED at the button is lit and possibly also one of the LEDs for
the domestic hot water comfort function. The gas boiler is waiting for
a space heating and/or domestic hot water demand.
Pump overrun of space heating
After each space heating operation, the pump continues to run. This
function is controlled by the indoor unit.
Boiler shutdown when the required temperature is reached
The boiler controller can temporarily stop the requested space
heating demand. The burner will stop. The shutdown occurs
because the requested temperature is reached. When the
temperature drops too fast and the anti-cycle time has passed, the
shutdown will be cancelled.
Self-test
The sensors check the boiler controller. During the check-up, the
boiler controller does NOT perform any other tasks.
Ventilation
When the appliance is started, the fan goes to starting speed. When
the starting speed is reached, the burner is lit. The code will also be
visible when post-ventilation is taking place after the burner has
stopped.
Ignition
When the fan has reached its starting speed, the burner is ignited by
means of electric sparks. During ignition the code will be visible on
the service display. If the burner does NOT ignite, a new ignition
attempt occurs after 15 seconds. If after 4 ignition attempts the
burner is NOT yet burning, the boiler will go into fault mode.
Daikin hybrid for multi heat pump – heat pump module
bar
1.4 1.6 1.8 2.0
CHYHBH05+08AA + EHYKOMB33A
4P471761-1A – 2017.10