Panasonic 9kw Aquarea wiring diagram

[Pete]

Can anyone of our electricians @ProDave please explain how this wiring diagram will work on my Panasonic 9kw Aquarea heat pump?Secon Panasonic H Series rev1.3.pdf  I understand that the heat pump will require its own supply from the CU but I am a little unsure as to what cables to put in ready for my sparky mate to connect everything up. I think I need to run some 1.5mm flex to run the heat pump ,diverter valve and controls etc but not sure if the power supply for this is fed from the heat pump supply via some fused spurs or if the heating controls are fed from a different source to the main heat pump supply? I understand it would be ideal to have one isolator for the whole heat pump and assoc controls but just a little confused? 

The heat pump itself has a back up heater for DHW so this is also confusing me as it shows connections for the immersion heater in the drawings but I assume this is the one on my HW cylinder so not sure if the feed for the immersion heater should come via the main heat pump supply?

I am just trying to get all my cables in place ( so I can plaster some ceilings ) plus some spare ready for when my sparky is available to connect it all up next month so we can get moved in before xmas and I still have plenty to do! 

Hope you can help me understand this? TIA

[ProDave]

Okay you have the 9kW version so the main supply cable needs to be at least 4mm, preferably 6mm fed from a 32A mcb in the CU with a 32A waterproof rotary lockable isolator in the wall by the heat pump.  there is also a secondary power supply rated at 16A which I would wire in 2.5mm

 

Referring to page 3  the Panasonic controller and tank temperature probe are pre made cable assemblies that should just plug in.

 

The immersion heater in your hot water tank connects by a 3 core I would use 2.5mm cable though 1.5mm would do.

 

Then at the bottom there are some valve connections.  I found the easiest way to connect things like that is with a length of 0.75mm multicore control cable and just bring one multicore cable from the heat pump to a witing centre in the house where the pumps and valves are.  Personally I would use a 10 core control cable and connect all the terminals on the bottom of that PCB including the ones not shown as used.

 

There is no other power needed for the valves and pumps, they literally connect to the PCB as shown and all power they need is sourced from that pcb.

 

This is a vitrually identical setup to my own LG unit where the heat pump controls the valves and pumps in much the same way.

 

The mention of local switches is just because they are controlled remotely and may power up at any time, so they are suggesting local isolation for anyone working on them.  Personally I took the view that it is no different to a normal central heating pump that may start under the control of a time clock or thermostat at any time and anyone with half a brain working on the pump would turn off the whole heating system at the CU.

 

to elaborate on the immersion heater.  The immersion heater power is the second power supply, the 16A 1, so at the CU label that "immersion heater" with a note (via ASHP)  then you have the cable from the ASHP to the immersion heater in your hot water tank, which will have it's own local isolation switch.  the reason it is wired like this, is so the ASHP can control the immersion heater either as a backup source, or for periodic legionairs cycles to heat the water much hotter at intervals.

 

 

 

[Pete]

3 minutes ago, ProDave said:

Okay you have the 9kW version so the main supply cable needs to be at least 4mm, preferably 6mm fed from a 32A mcb in the CU with a 32A waterproof rotary lockable isolator in the wall by the heat pump.  there is also a secondary power supply rated at 16A which I would wire in 2.5mm

 

Referring to page 3  the Panasonic controller and tank temperature probe are pre made cable assemblies that should just plug in.

 

The immersion heater in your hot water tank connects by a 3 core I would use 2.5mm cable though 1.5mm would do.

 

then at the bottom there are some valve connections.  I found the easiest way to connect things like that is with a length of 0.75mm multicore control cable and just bring one multicore cable from the heat pump to a witing centre in the house where the pumps and valves are.  Personally I would use a 10 core control cable and connect all the terminals on the bottom of that PCB including the ones not shown as used.

 

This is a vitrually identical setup to my own LG unit where the heat pump controls the valves and pumps in much the same way.

 

 

 

Thanks Dave for the reply. Just to clarify I would put  a 4mm from the CU to the waterproof isolator and then run cables back to the wiring centre and then put in some fused spurs so I can isolate the thermostat and immersion heater? You mention the immersion heater and 2.5mm/1.5mm cable but is the power for the immersion coming from the heat pump main supply or elsewhere? 

[ProDave]

3 minutes ago, Pete said:

Thanks Dave for the reply. Just to clarify I would put  a 4mm from the CU to the waterproof isolator and then run cables back to the wiring centre and then put in some fused spurs so I can isolate the thermostat and immersion heater? You mention the immersion heater and 2.5mm/1.5mm cable but is the power for the immersion coming from the heat pump main supply or elsewhere? 

I think I added the explanation to that as an edit after you quoted my original post.

[Pete]

2 minutes ago, ProDave said:

I think I added the explanation to that as an edit after you quoted my original post.

I missed that so thanks for the clarification. My unit also has heater back up heater built into it. The waterproof isolation switch has four terminals  and my unit is the 9kw standard and not the TCAP so it is saying I only need a 2.5mm for the main supply and a 1.5mm for the second supply so I have plenty of 4mm cable left so would it be ok to run a 4mm supply from the CU to w/proof isol and then run a 2.5mm and a 1.5mm from the isol switch to the heat pump and then back to the wiring centre? TIA

[ProDave]

Yes that would be fine.

[Pete]

3 minutes ago, ProDave said:

Yes that would be fine.

So trying to understand the way the heat pump works and future proofing for solar PV what would I need to take into account so I can make use of the PV to let the immersion heat the HW instead of the heat pump? I need to make sure that the way the system is wired will be compatible with solar PV when we fit it next year please? 

[ProDave]

1 minute ago, Pete said:

So trying to understand the way the heat pump works and future proofing for solar PV what would I need to take into account so I can make use of the PV to let the immersion heat the HW instead of the heat pump? I need to make sure that the way the system is wired will be compatible with solar PV when we fit it next year please? 

That might get more complicated.  My own LG heat pump deals with the immersion heater differently by having a "sanitary water controller" which is a posh name for a tin box containing a contactor that switches the immersion heater.  yours has the switching built in.

 

By far the simplest if you have not got it yet would be get an extra immersion heater fitted when you order your tank and keep them separate.

 

Worst case you might have to do some switching to isolate the immersion from the ASHP for the solar PV diverter.  Or do as I did take the view with mains water and an unvented tank you don't need to to legionairs cycles so disable that function and just use the immersion for the solar PV diverter.

[Pete]

12 minutes ago, ProDave said:

That might get more complicated.  My own LG heat pump deals with the immersion heater differently by having a "sanitary water controller" which is a posh name for a tin box containing a contactor that switches the immersion heater.  yours has the switching built in.

 

By far the simplest if you have not got it yet would be get an extra immersion heater fitted when you order your tank and keep them separate.

 

Worst case you might have to do some switching to isolate the immersion from the ASHP for the solar PV diverter.  Or do as I did take the view with mains water and an unvented tank you don't need to to legionairs cycles so disable that function and just use the immersion for the solar PV diverter.

I was thinking that I would not need that function of the heat pump controlling the immersion heater so may just put the cable in place between the isol switch/heat pump and immersion heater just in case and do as you say and wait for the PV diverter to feed the immersion.

I notice that the heat pump can be used to cool but not sure how to do this? I think it is via the controller but I notice there is a terminal in the wiring centre marked cool so how do I go about this please?

Edited November 23, 2020 by Pete

[Nick Laslett]

Pete, great questions. I would like to be brave enough to fit a Panasonic ASHP. 
 

I believe that @jack has a Panasonic ASHP with cooling mode engaged. I think you need a service menu code to enable it. 

[jack]

9 hours ago, Nick Laslett said:

I believe that @jack has a Panasonic ASHP with cooling mode engaged. I think you need a service menu code to enable it. 

 

Yes, I have, and yes, you do. From memory, when I unboxed it there was a separate piece of paper with instructions for unlocking the cooling mode. Somehow that went missing, but I was able to find it by searching online. I didn't save the link or the info, unfortunately, but I'm pretty sure you just need to get into the service settings, and it's a simple on/off setting. 

 

11 hours ago, Pete said:

I notice that the heat pump can be used to cool but not sure how to do this? I think it is via the controller but I notice there is a terminal in the wiring centre marked cool so how do I go about this please?

 

As I guess you know, the terminal is just an input to allow a thermostat to call for cooling. You still need to enable it in the settings.

[Pete]

4 hours ago, jack said:

Yes, I have, and yes, you do. From memory, when I unboxed it there was a separate piece of paper with instructions for unlocking the cooling mode. Somehow that went missing, but I was able to find it by searching online. I didn't save the link or the info, unfortunately, but I'm pretty sure you just need to get into the service settings, and it's a simple on/off setting. 

 

As I guess you know, the terminal is just an input to allow a thermostat to call for cooling. You still need to enable it in the settings.

 

Thanks Jack. I have read through the controller manual a few times and I think it is in there but no mention of what to do with the cooling terminal as you say it is a means of connecting thermostat to heat pump for cooling purposes

[ProDave]

2 hours ago, Pete said:

Thanks Jack. I have read through the controller manual a few times and I think it is in there but no mention of what to do with the cooling terminal as you say it is a means of connecting thermostat to heat pump for cooling purposes

My LG ASHP has a terminal for an ordinary room thermostat.  When that is activated, the HP starts up in heating mode, with the heating water delivered at the temperature set for heating.

 

It also has a terminal labelled "cooling"  give that the same 240V from a cooling thermostat and the HP will start up in cooling mode delivering chilled water at whatever temperature it says in the setup.

 

And by experiment if you activate both, cooling takes priority and it starts in cooling mode.

 

That behaviour will vary from one make to another no doubt.

[Pete]

6 hours ago, ProDave said:

My LG ASHP has a terminal for an ordinary room thermostat.  When that is activated, the HP starts up in heating mode, with the heating water delivered at the temperature set for heating.

 

It also has a terminal labelled "cooling"  give that the same 240V from a cooling thermostat and the HP will start up in cooling mode delivering chilled water at whatever temperature it says in the setup.

 

And by experiment if you activate both, cooling takes priority and it starts in cooling mode.

 

That behaviour will vary from one make to another no doubt.

How can both be activated at once Dave? 

[PeterW]

9 hours ago, Pete said:

 

Thanks Jack. I have read through the controller manual a few times and I think it is in there but no mention of what to do with the cooling terminal as you say it is a means of connecting thermostat to heat pump for cooling purposes

If it’s this controller then it is fairly simple by the looks of it 

 

https://www.manualslib.com/manual/1273892/Panasonic-Wh-Sdc09h3e8.html?page=148

[ProDave]

1 hour ago, Pete said:

How can both be activated at once Dave? 

They would not normally, it was just an experiment I did as I like to know how things work.

[Pete]

3 hours ago, PeterW said:

If it’s this controller then it is fairly simple by the looks of it 

 

https://www.manualslib.com/manual/1273892/Panasonic-Wh-Sdc09h3e8.html?page=148

It looks like mine but so confusing to have a cooling terminal and no connection or am I not looking at it right? Many thanks

[PeterW]

8 hours ago, Pete said:

It looks like mine but so confusing to have a cooling terminal and no connection or am I not looking at it right? Many thanks

sorry not following you ..?  
 

If it’s the same / similar then try the key press to get into the service menu and see if cooling is there to start with. No need to change any settings. 
 

Do you have a cooling terminal on the main board itself ..?? If so it’s a NV dry contact I think that you just close to make and cooling will start. You would do this with another room stat set at say 25c or higher. 

[Pete]

2 minutes ago, PeterW said:

sorry not following you ..?  
 

If it’s the same / similar then try the key press to get into the service menu and see if cooling is there to start with. No need to change any settings. 
 

Do you have a cooling terminal on the main board itself ..?? If so it’s a NV dry contact I think that you just close to make and cooling will start. You would do this with another room stat set at say 25c or higher. 

Just need to make sure I have all the possible wiring on place and some are saying all you do is change the controller settings and you are now saying I need another stat to control the cooling so getting a little confused as to what I actually need to do. I think the heat pump has a cooling terminal but as if yet it is still packaged up outside. Thanks for your time

[PeterW]

1 minute ago, Pete said:

Just need to make sure I have all the possible wiring on place and some are saying all you do is change the controller settings and you are now saying I need another stat to control the cooling so getting a little confused as to what I actually need to do. I think the heat pump has a cooling terminal but as if yet it is still packaged up outside. Thanks for your time

OK so it is both ..!! 
 

The controllers are shipped with the cooling disabled in the firmware. If you didn’t enable it, then irrespective of what you do to the cooling request terminals which are physically on the board, you wouldn’t get a response. Enabling it allows the unit to respond to an input on the board. 
 

You need a cooling thermostat irrespective if you want cooling to work, as your current thermostat will be a heating stat - it will close a set of contacts to call for heat when it is below a set temperature, and open them when it reaches or exceeds that temperature. It won’t care if it is 0.5°C or 10°C above the set temperature, it will do nothing...!

 

What you need to install is a cooling stat that has a set of contacts that close when it goes above a certain temperature (let’s say 23c) and then cooling will enable. When it drops below, they open and cooling stops. 
 

This normally means using the NC contacts to drive the cooling on some stats, or you may find one that has a “Cooling” setting that reverses the logic in the thermostat itself. In the US you can buy AC control stats that allow both from

the same unit but I’ve never seen one over here. 
 

The thing to ensure is you don’t overlap the heat and cool ranges so it doesn’t cool too far then flip to heating to bring it back up etc. 
 

Hope that clarifies. 

[Pete]

5 hours ago, PeterW said:

OK so it is both ..!! 
 

The controllers are shipped with the cooling disabled in the firmware. If you didn’t enable it, then irrespective of what you do to the cooling request terminals which are physically on the board, you wouldn’t get a response. Enabling it allows the unit to respond to an input on the board. 
 

You need a cooling thermostat irrespective if you want cooling to work, as your current thermostat will be a heating stat - it will close a set of contacts to call for heat when it is below a set temperature, and open them when it reaches or exceeds that temperature. It won’t care if it is 0.5°C or 10°C above the set temperature, it will do nothing...!

 

What you need to install is a cooling stat that has a set of contacts that close when it goes above a certain temperature (let’s say 23c) and then cooling will enable. When it drops below, they open and cooling stops. 
 

This normally means using the NC contacts to drive the cooling on some stats, or you may find one that has a “Cooling” setting that reverses the logic in the thermostat itself. In the US you can buy AC control stats that allow both from

the same unit but I’ve never seen one over here. 
 

The thing to ensure is you don’t overlap the heat and cool ranges so it doesn’t cool too far then flip to heating to bring it back up etc. 
 

Hope that clarifies. 

Let me read again later and I will let you know! Many thanks

[Pete]

The electrical isolation switch for the heat pump has to be mounted adjacent to the heat pump. I remember @Jeremy Harrislocating his immediately on the inside of his house on the other side of the wall from the heat pump. What are the regulations for this switch as I have also seen the switches mounted on the heat pump itself? I have some really nice stone cladding behind my heat pump and I do not want to drill/ mount my switch onto this. TIA

[ProDave]

My isolator is on the outside of the wall next to the heat pump.

 

The idea is someone that comes to service it knows they can isolate the supply.

[Pete]

1 minute ago, ProDave said:

My isolator is on the outside of the wall next to the heat pump.

 

The idea is someone that comes to service it knows they can isolate the supply.

I appreciate that but I just wondered if the regs state it has to be within a certain distance? With Jeremy putting his inside the house and then could possibly sell and move on and somebody else take over the property then the isolator would be nowhere near the pump but who is to say he put it in the wrong place?

[Pete]

On 30/11/2020 at 21:21, Pete said:

I appreciate that but I just wondered if the regs state it has to be within a certain distance? With Jeremy putting his inside the house and then could possibly sell and move on and somebody else take over the property then the isolator would be nowhere near the pump but who is to say he put it in the wrong place?

I am currently going round in circles trying to get our house ready to  move into and keep on getting conflicting advice. I have received more info today from the heat pump supplier and the wiring diagram is different to the original one. Whilst I know there are numerous ways to wire heating systems I am getting so confused as to which way to go. The heat pump guy suggests the best way to go is to let the heat pump run the buffer tank and that is the easiest way to do it but my sparky mate is proper old school and is not so sure of what is the best way other than a traditional room thermostat. The Panasonic controller is a real fancy bit of kit and can seem to do most things but the two wiring diagrams I have received from the supplier differ slightly. Plus how can the heat pump control the buffer tank as the buffer tank has no sensor, it is purely a buffer tank with no coil etc??

Please see drawings as you can see that the circ pump (ufh) and thermostat wiring is different so not sure what is the best way forward? TIA

ASHP Drawing.docx