Samsung RC090MHXEA User manual

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Air Source Heat Pump
Installation and Maintenance Manual
Heating only Hybrid
Model Numbers:
RC090MHXEA
RC160MHXEA

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Hybrid or Bi-Valent heat pumps
A hybrid or Bi-valent heating system uses a heat pump and the existing boiler
together. They are set up to NEVER run at the same time.
This type of system is popular as it means there is no work required to modify the
existing heating system, all radiators are kept the same as is pipework controls etc.
Like a hybrid car when the going is easy the electric system operates and when the
going is hard the oily bit does the work.
In the case of the heating system when the outdoor temperature is warmer (typically
above +3C) the heat pump will heat the house and when the temperature is cold the
boiler will take over.
We normally recommend the old boiler continues to supply hot water and the heat
pump helps out with just the heating, this is especially true if you arre using a combi
boiler.

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The outdoor unit (boiler)
Deciding on Where to Install the Outdoor Unit
The outdoor unit must not be placed on its side or upside down, as the compressor lubrication
oil will run into the cooling circuit and seriously damage the unit.
Choose a location where the noise of the Air to Water Heat Pump when running and the
discharged air do not disturb any neighbours.
Install the outdoor unit on a flat, stable surface with plenty of drainage, gravel or grass is
ideal; make sure the base can support its weight
Position the outdoor unit so that the air flows into an open area.
Place the outdoor unit where there are no plants and animals
When installing the outdoor unit near sea make sure it is not directly exposed to sea breeze.
The golden rule is, if you can see the sea from the position of the outdoor unit you need to
apply Blygold or equivalent anti-corrosion coating on the whole unit.
The unit needs to be securely
mounted at least 100mm off the
ground on rubber feet or wall
brackets, the unit must be bolted
down for security using 10mm bolts and
Zebedee bolts.
The unit must have adequate
drainage away from the unit; it can
produce up to 6 L / hour.
There is a drainage kit included
which we recommend you don’t
use, its best to let the unit drain into the ground. The drain holes in the unit are clearly shown,
if a drip tray is used it must be 25mm longer and wider than the base of the unit to catch all
the drips.
Dimensions:
Size 16 - 1420mm (h) 940mm (w) 330mm (d) 103kg
Size 9 - 998mm (h) 940mm (w) 330mm (d) 75kg
The space around the unit is very important, allow:
150mm to the left hand side (facing the front of the
unit), 600mm to the right of the unit, 300mm to the
rear of the unit and 1500mm to the front of the unit.
The unit will not benefit from being mounted on the
North or South of the building any aspect is fine, you
should avoid very exposed positions to avoid wind blowing into the back or front of the unit
and very sheltered positions.
An exposed location may increase difficulty for full unit defrost.
The Control Box
When the heat pump is delivered it comes with a control box which also contains the flow
switch. Install the control unit indoors as it’s not waterproof.
It needs to be sited within 15m of the hot water cylinder, 100m of the outdoor unit and as near
as possible to the pump, flow switch and any zone valves.
The box is 323mm wide, 339mm high, 131mm deep

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The heat pump unit has 1 inch BSP male connections; these should be connected to flexi
hoses (supplied).
To maintain flow rate we recommend 28mm pipework is used with this machine. NEVER
use 22mm plastic tube, if you insist on using plastic use 28mm throughout
All Pipework including the flexis need to be insulated with 23mm lagging
It is essential to connect an expansion vessel, pressure gauge, pressure relief valve, filling
loop, magnetic filter/strainer and automatic bypass.

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Other components you need to supply and
fit:
An expansion vessel, pressure gauge, pressure relief valve and filling
loop
Most heating engineers use a robokit with the appropriate size expansion vessel; this is sized
exactly the same way as when using a boiler.
Pump
Your pump needs to supply 20l/min for the 9kW and 30l/min for the 16kW unit.
The static resistance through the unit is 10kPa for the 9kW and 15kPa for the
16kW unit. The flow meter has a resistance of around 5kPa
The cylinders (Gledhill) have a static resistance of 5kPa for the heat pump coil
and 19kPa for the solar coil.
The total resistance of the components will be approximately 39kPa for the size 9 unit and if
the cylinder is piped using both coils and approximately 44kPa for the size 16 unit if using
both coils.
Flow switch and flow meter
The unit requires 16L / min flow at all times, if you don’t achieve this
E911 error will occur to check this flow switch is installed. The flow
switch comes with the control box.
The flow Switch MUST be installed either horizontally or vertically with at least 150mm of
straight pipe either side, connection is 1” female BSP. The wire is 2m long and needs to
connect into the wiring station. This wire can be extended to suit. We recommend a flow
meter is installed into the flow side of the flow switch as per the photo. Adaptors may be
required to enable this join. The flow switch is not IP65 rated (weatherproof) and so must not
be installed externally.
Diverter valves
You will need to put a 2 port valve on both the heat pump and the boiler to shut
them off when they are not operating, you need to supply these. The valve on
the heat pump can be a single check non return valve.
Bypass Valve
You must install a bypass valve in the heating circuit as far away from the heat
pump as possible. The bypass valve enables flow to be maintained as the trvs
shut down at all times to prevent unit flow fault.
Buffer vessels
We don’t normally use buffer vessels on Samsung EHS systems; as long as the water volume
circulating is over 20 Litre. The inbuilt variable speed compressor means the unit can operate
without a buffer.
1m of 22mm pipe holds 380 ml of water, if you add the volume in the unit and components
and make sure you put the bypass valve more than 25m from the heat pump your system
volume will be adequate. When utilizing multiple units, a buffer or low loss header is required
to hydraulically join the units.
Magnetic Filter
A magnetic filter with strainer must be installed in the return to the unit. A magnetic filter
ensures that debris/foreign materials do not cause restrictions within the pipework / system.
Glycol
A propylene glycol mixture must be utilized to prevent freezing of the water within the system.
It is important that the glycol concentration is adequate to protect the unit in case of power
failure in very cold conditions. If the unit freezes up there will be no warranty. Manufacturer
dependant, a mix of around 25% should suffice.

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Wiring and Power Supply Information
Power
The EHS system needs 2 power supplies:
One connects into the outdoor unit, 20 Amp for the 9kW and
32 Amp for the size 16
The one for the control box is 3 Amp and wires into the top of
the breaker (mcb) in the box
Communication cable
This must be run from the outdoor unit to the control box. Use
2 core flex 0.5-1mm (its 16V ac)
Sensors
Sensors cannot not be cut or extended. Keep sensors away from mains cables please
The blue cylinder sensor is not required it is normally used in the cylinder
The red safety sensor is to avoid over temperature, clip it to
the outlet of the combi boiler. It plugs into a red socket T3 on
the controller PCB
There is a black wire with a red plug in the box, this is not used.
Diverter Valves
2 port valve no 1 for the heat pump wire B6 live and B5 Neutral, this opens when the heat
pump is running.
Thermostats/ timers and under floor heating manifolds
It is now possible to use a single set of controls to drive both systems using a simple
relay,
Heating should be controlled by an external field supplied room stat / setback stat time clock
etc. or run signal from a boiler enable signal from under floor manifolds.
Make a connection from B20 – B24, to run the unit B20 is permanently live 240V ac. B19 is
Neutral
When the stat is made the heat pump will run, when the stat opens the unit will stop. NOTE
the pump will run on for 6 minutes after the unit is told to stop.
Pump
The circulation pump must be wired Live to B6 and neutral to B5, MAX pump power is 500
Watts. If two pumps are used wire them both to these terminals

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NOTE terminal
positions
are relevant for this relay only. The terminals are both
normally open; they close when relay is powered.
In cold weather B4 sends a live signal out from the heat pump to the relay, when relay is
switched on this live is sent to the 2 port and the boiler runs. In warmer weather B4 is dead
so the run signal to the heat pump makes it operate, boiler will be off.

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Start Up Procedure:
Checklist
Outdoor unit:
Is there 300mm to the left of the outdoor unit?
Is there 600mm to the right of the outdoor unit?
Is there 300mm to the rear of the outdoor unit?
Is there 1500mm at the front of the outdoor unit?
Is the unit more than 100mm above the ground?
Have you allowed for the unit drainage?
Is there a power supply to the outdoor unit?
Indoor control box
Have you stuck the yellow sticker (attached) to the front of the unit?
Is there a separate supply for the indoor control box
Have you wired in a room thermostat? OR a run signal from ufloor
manifold
Is the Samsung remote controller well out of reach of the end user?
The plumbing:
Is plastic pipe being used? If so is it all bigger than 22mm?
Is a flow meter installed directly into the flow switch?
Is the flow switch horizontal?
Is there 150mm of straight pipe either side of the flow switch?
Is the cylinder sensor plugged in 2/3 of the way up the cylinder?
If the pump is a variable speed type is it set to meet max speed within
10 seconds?
Is there a filter before the return to the heat pump?
Have you installed a bypass valve or allowed for bypass?
Have you got your glycol ready to put in the unit?
Have you lagged all external pipework?

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Start-up Procedure:
Filling and flushing:
The Building Regulations for England and Wales, Part L, 2006, now require a central heating
system to be cleaned and inhibited chemically whenever the boiler is changed or any major
works are carried out to the system. When installing any Heat pump we insist on a thorough
system flush prior to connection of the new equipment, your warranty will be at risk if a
suitable flush is not carried out and the system becomes blocked during normal operation.
The recommended procedure is to power flush the system in both forward and reverse
directions at 110% of the normal flow rate and to use a chemical flushing agent where
required.
Filling
Using the power flusher fill the system with water and 25% Propylene Glycol to more than 1
bar. DON’T fill the unit with a hose expecting no air locks, the heat pump is prone to air
locking at the outdoor unit, there is no auto air vent here. Don’t pour neat glycol into the unit;
there is no chance of the heating pump moving neat glycol around the system.
With the power OFF, remove the front of the remote controller, slide it upwards, turn it over
DON’T TOUCH THE PCB, there are 8 dip switches near the red sensor, using a small
screwdriver flick dip switch 1 and 5 to on. Cooling will no longer be available. Put the
controller back on the wall.
On the outdoor unit remove the front cover, there are 2 screws at
the top and one at the bottom, slide the cover down. Inside the unit
on the back of the white switch box there is a baseplate heater
PCB see picture. Which is not normally required in the UK,
disconnect the bottom wire with the white plug and tuck it out the
way
Powering Up
Apply power to indoor control box first then the outdoor unit.
In the middle of the control box PCB you will see two tiny leds one
red and one orange flashing. The red one shows the signal leaving
the PCB and the orange shows the signal coming back from the outdoor unit. If this doesn’t
happen check there is power on at the outdoor unit. Check the comms cable between the
outdoor unit and the control box F1 and F2.
Put the cover back on the outdoor unit.