@gery I know when I look at my octopus energy account there are options (my devices) to allow octopus app to access the Octoups Daikin heat pumps. For example they control my Tesla batteries in the solar months. 
it must be complicated if you have both the homely and Octopus and the Daikin controller all interlinked, but homely can work in smart + mode with the octopus TOU tariffs, so theoretically it should be ok. I wonder if there’s a conflict.

@majordennisbloodnok Yes, we did, at that time, Octopus were surveying our house and the possibilities; we felt that a horizontal tank in the loft was a possible option but not with them and only if we enlarged the loft trap to do so. OE were not keen on going outside their ‘scope’ to fit anything beyond basic layouts. By the time we had chosen our installers, we had discounted the additional work involved and the greater heat losses with not having a heated airing cupboard. Toodles.

@majordennisbloodnok Might this help?

@toodles thank you for your response. I have a couple of questions on your heating integration that I hope you can help with.

1) Do you get error red error messages on the RS845 LED on the Daikin Modbus adapter? I guess it depends on how accessible it for you to check - mine flashes green then around 5 red flashes which I think indicates some sort of error code.

2) Do you think you installer might be able to help if he has done a Daikin/homely integration? I'm in North Somerset so may be not close to you?

Thank you for being so open and helpful!

@papahuhu

This is a still from a video. Top left (10&11) is the two P1 & P2 wires going from the main Daikin unit to the Modoka thermostat that I've stuck the Modbus in the 'daisy chain'. Apparently the Modbus can he anywhere in the daisy chain - sometime on the heat pump? Bottom left (1&2) is power and the two terminal next (3&4) to it with the resistor across are the input from the homely controller. If I switch off the Homely controller then I don't get the red flashing error on the RS485 but equally then I have no control! The bottom dip switch is the only one 'on'.

@gery Sorry Gerry, mine is configured by adding an interface board on the heat pump itself. You do know that there are homely installation videos on YouTube that show you exactly how to install it and test the installation. Both with the just the controller and also with the controller and thermostat. If the full daisy chain isn’t working I’d be inclined to try it without the thermostat and see if the fault goes. I don’t really understand why you’d want a thermostat if you are using the homely, it has its own temp and light sensor. Mine is integral with MMI and left that in the garage with all the other hardware as it’s not needed for anything on a day to day basis.

Posted by: @gery

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@papahuhu

This is a still from a video. Top left (10&11) is the two P1 & P2 wires going from the main Daikin unit to the Modoka thermostat that I've stuck the Modbus in the 'daisy chain'. Apparently the Modbus can he anywhere in the daisy chain - sometime on the heat pump? Bottom left (1&2) is power and the two terminal next (3&4) to it with the resistor across are the input from the homely controller. If I switch off the Homely controller then I don't get the red flashing error on the RS485 but equally then I have no control! The bottom dip switch is the only one 'on'.

OK, so I'm going to preface this post by saying I haven't got a Daikin and have never dealt with a DCOM unit before so I am far from an expert. However, I do know a little about modbus and I've got the DCOM and Homely reference manuals in front of me so for what it's worth....

Can you double check and confirm that the other end of the wire going into terminal 3 (RS485 +) is connected to the correct Homely terminal (i.e. terminal A) and that the wire from terminal 4 (RS485 -) is connected to Homely terminal B? There are only three things to mess about with in a modbus installation (cables going to correct terminals, termination resistor installed or not and modbus address), and your photo shows everything at the DCOM end is set up exactly as the Homely manual lays out. The only thing it doesn't show is the other end of the cable, hence the double check.

@majordennisbloodnok Just in case there are variations in how the D.comm is configured, I am attaching a PDF of the manual for mine; though TBH, I suspect this is already what you have to hand Major.

Regards, Toodles.

@toodles I thought I’d enter the Temple Of Apollo to seek wisdom from the Homely savant.
To position my question, I’ve got to take a couple of rads off to repair some lining paper from my heat pump install. My plan was to turn off the heating via the homely, close the radiator valves, drain the rads and lift them off. I’m not the fastest DIYer and hate wallpapering, but to cut a long story short,  I don’t want the heating to come on unexpectedly.
The other day I received a comms from homely about something and I’m sure it said something about even if the heating is off, the system will override this status if the temp drops below 12C and automatically start the heating. For a start, that seems a bit odd, if you turn something off you expect it to remain off. But my question is more specific, do you happen to know if the 12C measurement reference point is OAT or IAT please? I don’t fancy the contents of my central heating spraying across the rooms whilst I get chastised for taking so long to decorate.
 
much appreciated, I don’t have any of those blanking plugs and don’t want to have to buy a load to add to my pile of things I use once and forget where I put them. My workbench is like the krypton factor.
 

@papahuhu ‘Savant’ ??? Well I’ll try!🤨

As you say, the 12 degrees C default - this I believe to be the IAT reading. In fact, most (if not all?) heat pumps have their own protective settings that switch on when the OAT drops near freezing and these usually start a pump running (and presumably, the compressor) to protect the whole system from damage.

As to the system ‘firing up’ whilst you are carrying out work with an open run of piping, the safest move would be to isolate the mains to the complete heat pump system whilst you are working on the plumbing. I am not aware of any system problems if the whole system is switched off - mine (A Daikin + Homely) doesn’t bear me any grudges when I have switched off the isolator. When turned on again, the system resets itself within a matter of minutes and returns to normal. Others may be able to say if there are heat pumps that don’t care to be treated in this way.

I know what you mentioned but I would still be inclined to obtain a decorator’s cap and as long as you have some old absorbent cloths / rags and / or a draining tray, you should be able to keep the site clean and dry.

I have seen various YT guides on removing a radiator without mishap - it probably does look easier in their hands than in my or possibly your hands - but worth watching.

I bought a pack of 10 caps but I think you can buy them in smaller quantities. I wanted them because I wished to remove the TRV’s anyway - it is neater and I know that they are not restricting the flow when just screwed on loosely. Perhaps I have been fortunate but my plumber has left me with sealing caps for the LSV bodies as well. Regards, Toodles.

@toodles Thanks, so it’s true. saw they are discounting them, I guess it’s because I registered as an installer, that’s not a good sign, having premonitions of Givenergy.

Unlike you, I won’t get hot water if i power down and history tells me I take a long time to do things I hate! I think I have seen some TRV caps about.
I can use it as an excuse for my better half as to why I haven’t started. It did get down to 13C last night so I wouldn’t be totally fibbing. 

Isn’t the sun fab recently, been exporting about 60 kWh a day for last week as the trees are only marginally shading the roof. 

thanks again

@papahuhu My best days have provided just short of 50 kWh’s but most days recently have made `42 or so. (8.1 kWp. with less than ideal orientation and some shading).