Legionella Protection; When It Goes Wrong; Checking The Immersion Heater - Samsung RC090MHXEA Service Manual

Legionella protection

Legionella
The legionella function operates the immersion heater in the hot water cylinder once a week
or every day to disinfect the hot water tank.
We normally encourage engineers to set the legionella function to start at 3 am on Tuesday
morning and to heat the tank to 60C for 10 mins. This is adjustable in the field settings
How it works
When the legionella timer (in the unit) starts the immersion heater is
used to heat the cylinder, the heat pump stops operating. Note the
legionella symbol shows but there is no pump symbol.
Legionella can be adjusted in the field settings:
Setting 3041 turns legionella on and off, NEVER turn it off
Setting 3042 tells us the day legionella will happen; you can choose
any day or every day.
Setting 3043 is the time legionella will start
Setting 3044 is the temperature the unit wants to see in legionella mode set it to 60C
Setting 3045 Duration is how long the heater continues to operate once the temperature in
3044 is met.

When it goes wrong

Legionella function only ends when the tank reaches the legionella set point.
If the immersion heater trips or is switched off the unit will gets locked in Legionella function. It
won't heat the house or the hot water cylinder.
How can I get the unit to heat if it is stuck in legionella?
To restart the heating, you must switch off and on the hot water function press top right button
2 times.

Checking the immersion heater

To test the immersion heater, use the test mode on page 2
To access service mode press
button together for 6 seconds. The controller will display
TEST.
Press weekly to test the immersion heater in the hot water
cylinder
Test the current of the heater using an Amp clamp; this
measures the total amount of current. It is important to only
measure the current in 1 wire at a time. It should pull 13 Amps
www.freedomhp.co.uk
blue set button and test
The Gledhill tank has an immersion heater with its own stat;
this MUST be set 10 degrees above the legionella set point.
There is a cut out (black button) in the centre of the immersion
heater this must be pushed in to operate.
©G Hendra Nov 18 9