E407 Fault Code High Pressure Trip, And Flow Rate Problems; Installing The Hp Switch - Samsung RC090MHXEA Service Manual

E407 fault code High pressure trip, and flow rate problems.

An E407 fault is caused by the unit tripping out
on high refrigerant pressure; it will be showing
on the PCB of the outdoor unit
In almost all cases its caused by crap in the
water heat exchanger. It's a very good idea
to disconnect the flexi hoses from the unit,
flush water through the unit backwards to
flush the crap out and then reconnect the
unit. Now continue below.
Test 1 reset the power to the unit, leave it off for
40 seconds. Once it's powered up does the
E407 error show again on the outdoor unit in the
first 60 seconds? If so the HP switch is faulty.
Call Freedom HP for advice, the HP switch will
need to be replaced. See below.

Installing the HP switch

Turn off power to outdoor unit, remove front
cover. On front of unit there are 2 service valves,
they are brass. Remove the front cover from the
left hand valve and check the valve is tight using
a 4mm Allen key (clockwise). Using a spanner
remove the bottom nut.
The HP switch needs to connect onto the bottom
flare connection and be done up nice and tight.
Once its tight crack open the front valve with the
Allen key anti clockwise 1 turn. Make sure you
can't hear any refrigerant leaks.
Once you are happy replace the cap over the
Allen key and do it up nice and tight
Plug the HP switch into the board, switch on the
unit and it will run.
www.freedomhp.co.uk ©G Hendra Nov 18 26