Heat Pump Pack 1 Install Guide (LWD 50A/SX + HMD1 SE)
|Heat Pump Pack 1 LWD 50A/SX + HMD1 SE Return Buffer|
|Heat Pump Pack 1 LWD 50A/SX + HMD1 SE with Return Buffer WPS61|
This is a brief guide to help with the planning, installation and pre-commissioning of the Omnie Heat Pump Pack 1 incorporating the alpha innotec LWD 50A/SX + HMD1 SE heat pump. Detailed information is available in the Operating Manuals provided by AIT Deutschland who manufacture the heat pumps. The Primary Operating Manual contains most of the installation information such as dimensions, the Supplementary manual contains the performance data for the single phase units which includes the LWD 50 A/SX
The LWD range consist of an outdoor thermal unit (LWD) and an indoor hydraulic unit (HMD). The LWD has the finned heat exchanger/fan unit, compressor, water heat exchanger and controls in a weather proof case.
The indoor HMD includes the circulating pump, pressurised system safety set, 12ltr expansion vessel, main control PCB and the User Interface encased in an expanded polypropylene box. 3 electrical supplies are connected to the HMD from the consumer unit as are the cables from the outdoor LWD unit. See the HMD Operating Manual for full installation data.
The Omnie air source heat pump packs always include a buffer tank to ensure effective defrosting and efficient operation.
A 60ltr wall mounted tank is supplied with pack 1. Make sure there is space in the house for this along with the HMD unit.
Locating the buffer tank under the HMD unit is popular with regular installers. The buffer tank connections are on the bottom with a 1/2″ tapping on the top for a vent valve. The buffer is also an excellent air separator.
Always consider carefully the location of all the components to comply with all regulations and with the manufactures instructions in the Operating Manuals. Ask yourself if there is enough space around the units for future maintenance and air flow. Check with the Operating Manuals for the minimum space required.
Good air flow through the outdoor unit is vital to the operation, the clue is in the name “Air Source”. Do not restrict the air movement through the unit in any way and be aware that the exhaust air could be as much as 10 degrees lower than the surrounding air so make sure it can dissipate and not lurk around the house or garden.
Snow and leaves can block the fins on the heat pump so consider this when choosing the location. It is best to keep it out of direct sunshine as they can get very hot in summer which will deteriorate the casing over time. West facing means that it will be subject to driving rain and wind which is not good. East and North are preferable in the UK as these are the driest least windy sides of a house. Remember when you need the heating most there wont be any benefit from placing it on the south side.
Floor or Wall Brackets
Choose whether your LWD unit is to fix to a wall or sit on a concrete base. Either option is supplied in the pack, alternative mountings are not an option. If the supplied brackets are modified or not used it may affect the performance and the warranty could be invalid.
During normal operation the outdoor unit collects moisture from the air, this is captured by an internal drip tray in the bottom of the unit which is fitted with a drain. The drain should be allowed to run away either to a building drain or to an underground soak-away. This condensate water comes from the air and is therefore inert and can be discharged into a normal soak-away or surface drain. It is important to keep the drain short and at a steep angle, it should also be lagged to prevent freezing.
Note the pipe sizes on the schematic because they may be larger than you would expect. This is vital for a reliable efficient system, smaller pipes will lead to problems.
The installation of a heat pump is notifiable work under the Building Regulations. The regulations are in place to ensure that important works are carried out to a minimum acceptable standard. Exceeding the standards will improve efficiency performance and reduce running costs. Always check with the local Building Control Department at your local authority before starting work. If the work is not registered it can cause problems when it comes to selling your property in the future or could invalidate insurance in the event of an indecent.
The LWD 50A/SX is MSC certified so can be the heart of an MCS certified installation. In order to obtain the MCS certificate the end user must have a contract with an MCS registered installation contractor. This must be in place before any work starts on the project. The MCS certificate process cannot be carried out retrospectively. Visit the MCS web site for further information.
In order to register for the RHI it is necessary to have an MCS certificate for the complete heating system. Check with the OFGEM guides to find out if your circumstances qualify for RHI registration.
An up to date EPC is also required for the RHI registration.
Planning permission normally requires a minimum energy rating for a property. The efficiency and low carbon emissions from a heat pump will help with achieving a good EPC rating which will help with getting planning permission on a new build.
Install Guide PDF
LWD Operating Manual Primary PDF
LWD Operating Manual Supplementary PDF
WPS60 Buffer Tank
|Setting out and Installing the Outdoor Unit|
Make sure you have all the components on the hydraulic schematic. Take note of the items that are excluded from the pack like pipework and lagging, isolating valves etc.
Wall Duct Kit
The Wall Duct Kit is an optional item that is a neat solution for wall penetrations. The kit consists of a 1000mm long 110mm diameter plastic duct with rigid foam insulation segments, 2 No. 28mm copper tubes fitted with a flat face 1″ BSP coupling on one end that connects to the 2 No. flexible hoses that connect to the heat exchanger in the outdoor unit.
Provision is made in the duct for the condensate drain and the cables.
Included in the kit is a sturdy moulded cover that is screwed to the underside of the heat pump covering the pipe and cable entry, the wall duct and the condensate drain. A moulded cover is included to cover the pipes at the rear between the unit and the wall.
The wall duct kit includes the flexible hoses so if this is not being used they need to be included separately.
Flexible hoses are supplied if the Wall Duct kit is not selected. The hoses connect to the heat exchanger in the outdoor LWD unit with 1″ swivel nut flanges with fibre gaskets that are supplied in the ancillary box. They are needed to prevent both vibration being transmitted into the pipework but also to prevent stress on the heat exchanger connections.
Positioning the Outdoor Unit; Floor Feet or Wall brackets
The pack will include either feet for mounting on a concrete slab or brackets for fixing to a wall. Whichever way you are mounting the unit it sits on 4 No. rubber bobbins that are supplied in the ancillary box. Note: – DO NOT REMOVE ANY OF THE CASING UNTIL THE UNIT IS IN POSITION and you are ready to connect the pipes and cables.
The hydraulic connections to the heat exchanger in the outdoor unit are accessed by removing the lid and the left hand end panel. A Torx bit is provided in the accessories box to help with this. Try not to lose the screws.
A foam rubber closing plate is included, this is slipped around the two hydraulic hoses when they are in position then slid down until it sits in a recess in the base closing it off to dirt noise and most importantly animal infestation. The cables are passed through the holes provided.
|Mounting the HMD1 SE|
The Hydraulic Module must be mounted in a weatherproof location with normal moisture levels, it contains sensitive electronics. An outhouse or garage is suitable but it must be frost free in winter.
The HMD is wall mounted so make sure you have a suitable wall available which will support the weight and allow access to the hydraulic and electrical connections. Note that the cables enter the right side of the casing with cable glands and sufficient space is needed to allow access to the wiring terminations.
It is feasable to mount the HMD above the WPS60 buffer tank
When removing the HMD from the packaging find the ancillary box and put it somewhere safe. Under the HMD unit you will find the mounting template; a cardboard rectangle with the drilling positions for the mounting holes. Place this on the wall where the HMD is to be mounted and drill the holes.
The fixings supplied with the unit in the ancillary box are suitable for brick, block or concrete walls. Plugs, nuts and washers are included. If mounting on a stud wall it will be necessary to make suitable arrangements beforehand
Ancillary Box Contents
Before mounting the unit on the wall remove the Safety Assembly from the box and using suitable thread sealant screw into the boss on the top left. Ensure the gauge is facing the front of the module.
|Heat Pump Pack 01 Hydraulic Installation|
Omnie supply a Filterball strainer with the pack. this is sufficient on a new system with underfloor heating. it is essentially a ball valve with a 0.7mm mesh gauze strainer in the ball. when in the off position the gauze basket can be removed and cleaned without the need for other isolating valves.
If adding the heat pump to an existing system the previously had a boiler fitted add a good quality magnetic filter after power flushing the pipework etc. The gauze strainer with 0.6-0.8mm mesh is still needed.
Beware; most Y type strainers are not suitable because the mesh is too small.
A clean hydraulic system is essential for efficiency and reliability. A chemical clean of the system is essential before putting into service to remove mill scale, installation debris and bacteria. all of which will clog the system and stop it working.
Bacteria affects modern low temperature heating systems because it is not sterilised by the temperature as it was in the past. Bacteria will produce slime that grows while corroding the metal components in the system and will block plastic underfloor heating pipes. Residual dirt and soldering flux is nutrient to bacteria, it will also block the narrow passages of the heat exchanger thereby increasing the running costs while reducing comfort.
The heating fluid is circulated through external pipes and the outdoor heat exchanger. In order to protect the components from freezing in the event of a power cut during exceptionally cold weather Omnie recommend and supply premixed water/glycol solution. Not only does this protect the system from freezing to -13degC it also protects against scale, corrosion and bacteria. Mono propylene glycol is mixed with de-mineralised water and supplied in 20ltr drums. The mixture also contains biocide and inhibitors to protect against infection and corrosion. Under normal circumstances the solution should be good for the life of the system. The fluid must be added to a clean system.
It is vital to balance the flow throughout the system. This must be done at the pre-commissioning stage and should include: –
The heat pump requires three separate power supplies;
These are connected to the indoor Hydraulic Module. The outdoor Heat Pump LWD unit is in turn connected to the Hydraulic Module (HMD).
If the HMD is to be installed remote to the consumer unit it can be helpful to use a 3 way auxiliary consumer unit close to the HMD with an isolator and 3 MCBs which can be supplied with a single cable from the main incomer.
In addition to the power supplies it is very useful to incorporate a Cat6 Ethernet cable between the HMD and the location of the broadband router. The controller includes Internet connection to a remote server for remote monitoring which must be hard wired to the router.
This wiring schematic should be read in conjunction with the Operating Manual for the Hydraulic Module HMD1SE.
Observe the IET wiring regulations latest edition and follow BS EN7671.
Connecting the Outdoor Unit to the Indoor Unit.
Electrical work must only be carried out by qualified electricians.
The LWD is pre-wired with 3 x 8m long cables. Two cables supply power to the controls and the compressor the third is a data BUS that carries all the operating data and control instructions. These cables have the terminal block code printed along their length; X7 is the compressor power, X10 is the control power and LIN is the data BUS.
These cables can be extended up to 25m total length by using the appropriate cable. The power cables must be selected by the installing electrician in accordance with the latest IET Wiring Regulations and BS EN 7671. The LIN BUS should be extended with a screened cable with a minimum of 3 cores with 0.75mm csa, SY type is suitable but connect the screen to the braid and anchor this to the Terry clip on the HMD electrical box as shown in the HMD manual.
When removing the HMD cover for the first time you will find a sensor cable coiled up and tucked behind the expansion vessel. This must be attached to the common return pipe as shown on the schematic using the thermal paste and cable ties supplied in the HMD ancillary box.
The domestic hot water sensor is supplied loose. The stainless probe is pushed into the middle pocket on the cylinder and wired into the X4-TBW/gnd.
The white box in the HMD ancilliary box is the Ambient Temperature Sensor (AT). this must be mounted on a north or north east wall ideally 2/3 of the building height or at least 3m off the ground. Cable is not provided for this and must be supplied by the installer (we dont know how long it needs to be). 0.5/0.75mm csa twin core flex is an economical choice for this, please dont use Cat.5 it doesnt give good results. Separate all sensor cables from power cables by at least 100mm.
A motorised diverter valve is provided to switch from heating to DHW production. This is wired directly into terminal X3, the black wire is the switched live and is connected to BUP, the brown and blue are live and neutral and wire into X10.
In all cases it is necessary to fit electric meters to the supplies feeding the heat generating elements of the heat pump. As the heat pump requires three separate supplies but only two need to be metered a guide to fitting the meters is provided. Omnie recommend and supply small meters that fit into the consumer unit next to the MCBs for simplicity. If there are no spare ways in the consumer unit they can be fitted in a separate box. The guide shows that the compressor and the heater must be connected to separate meters so that the end user can see where the power is being consumed. This helps to show when something is going wrong with the heat pump. It should also reassure the user that the heat pump is not using large amounts of electricity.
Download the Operating Manual Here
|Omnie Pack 1 Installation Guide|
Read the text carefully and refer to the Operating Manuals for the outdoor LWD 50A/SX and the indoor HMD1.
When all the system components are mounted and the pipework connected the system must be prepared for commissioning in accordance with the Domestic Building Services Compliance Guide. This will include pressure testing, chemical cleaning and flushing to remove debris then filling with the correct thermal fluid. Omnie advise that frost protection down to -10degC should be provided.
The ideal thermal fluid is the premixed solution supplied by Omnie. The solution is a base of de-mineralised water with propylene glycol added to -13degC frost protection. The solution is free of scale forming minerals and is buffered to ph7 to prevent corrosion. Filling the system is simple when using a Fill-Flush-Purge pump unit such as this one used for filling solar thermal systems.
Visit the pre-commissioning guide page for full instructions.
The heat pump must be commissioned by an Omnie approved technician. The heat pump must not be operated before commissioning.
When the installation is complete including the pre-commissioning and the electrical supplies are all connected the installer completes the Installer Pre-Commissioning Checksheet and return it to [email protected] to arrange a commissioning visit.
Allow up to 4 weeks for commissioning during busy times (end of autumn), we will try to fit you in at the earliest opportunity.
If the heat pump is started before commissioning damage Omnie not accept any responsibility for damage either to the heat pump or to the fabric of the building. The heat pump warranty is only active when commissioned.
The extended parts warranty is dependant on annual service inspections being carried by an approved technician.
Down load the Installer Check Sheet Here