Hi @peterr 

If you could provide details of the layout of your home, the location of the UFH, where the various controls are located, along with what pumps, valves and mixing vessels may have been installed, it should be possible to identify what may need to be improved.

Hi @peterr 

To set your system to operate in auto adaptation mode it is necessary to set DIP switch SW5-2 to the ON position. Section 5 in the installation manual gives details of where the DIP switch is located and how to make the change.

@derek-m 

I tried drawing everything out, but it just ended up a confused mess, so I'll try and describe it as best I can.

UFH is to ground floor only.  It has its own controller.  The ground floor is split into 3 zones, each with its own thermostat.  When one of the UFH zones calls for heat the controller turns on the circulating pump (dedicated to UFH) and opens the valve to the relevant zone.  The UFH has a mixer valve which ensures that the circulating water does not get too hot, this was important when we had our LPG boiler, but probably unnecessary now.  I assume that there is a control signal from the UFH controller to the FTC to indicate when it needs heat; this is a question that I asked our installer, but they have yet to answer.

First and second floor heating is radiators (8 all with TRVs) and towel rails (4).  The flow from the ASHP comes in to the airing cupboard on the first floor where the DHW tank is located.  There is a pump controlled by the FTC which circulates water to UFH, radiators and DHW tank.  Two 2-way valves are used by the FTC to control the flow, either to the tank, or to the heating circuits.  The remote controller for the FTC is located on first floor, on the wall outside the airing cupboard.

UFH is heating Zone 1 on the FTC, rads are Zone 2.

We have a Mitsubishi Wireless controller linked in to Zone 2 which is currently located on the second floor.

To my knowledge we don't have a mixing vessel, unless the installers have managed to hide it somewhere I can't see it!

I hope that gives you everything you need.

Thanks,

Peter.

Hi @peterr 

It is difficult trying to visualise how your system is actually configured and inter-connected. If you have a copy of this manual.

Ecodan_FTC5_-_PAC-IF062B-E__PAC-SIF051B-E_Installation_Manual_Instruction_Book__BH79D449H03_.pdf

It may be possible for us to figure this out.

On page 10, section 3.5 Local system, there are shown various possible layouts, I think yours will probably be the '2-zone temperature control', which if fully controlled by the FTC controller will require the various items of equipment to have been installed. Section 3.6 Piping diagram for 2-zone temperature control, lists the various items of equipment.

If all the component parts are installed, it should be possible to operate the system using Control option A, as shown on page 18.

If you can look inside the main controller box and see which of the Thermistor inputs and Output wiring is actually connected, it may then be possible to see what type and level of control it should be possible to achieve.

@derek-m 

Thanks Derek.

I probably won't get a chance to look at this until after Christmas. When I do I'll get back to you with what I find out. 

@derek-m 

Hi Derek,

I have now managed to take a look at the controller and wiring and as far as I can tell our system does not match any of the examples given in section 3.5 of the manual!

Regarding thermistors, we have wiring in to THW1, THW2 and THW5b.

Input IN1 is connected, I suspect that this is the heat demand from our UFH controller.

Inputs IN8, IN9 and IN10 are also connected, these are the meters for the MMSP package.

FTC remote controller is connected as expected, as are the Wireless Receiver and WiFi adaptor.

On the output side, we have OUT1 connected (TBO.1.1-2), OUT3 (TBO.1.1.5-6) & OUT4 (TBO.2.5-6).  OUT1 goes to the circulation pump OUT3 & OUT4 go to 2-way valves (one for DHW and one for heating).

Switches are set as follows:

SW1 - 1, 5 & 6 OFF, 2, 3, 4, 7 & 8 ON

SW2 - 2, 3, 4, 5, 6 & 7 OFF, 1 & 8 ON

SW3 - 1, 2, 3 & 7 OFF, 4, 5, 6 & 8 ON

SW4 - ALL OFF

SW5 - 1, 3, 4, 5, 6, 7 & 8 OFF, 2 ON

SW6 - ALL OFF

The final thing is that I cannot set the operating modes for the 2 heating zones independently, I should be able to according to the FTC manual, but I can’t!

To me it looks like a real bodge job that hasn’t been thought through properly.

Thanks,

Peter.

Hi @peterr 

Thanks for the detailed information.

My wife and I are going out for the night, and whilst I would much rather stay at home and help you with your problem, I'm afraid that 'she who must be obeyed' actually must be obeyed on this occasion. 🙄

I will compare your systems settings against the manual, and hopefully propose a solution.

@derek-m 

Hi Derek,

Happy New Year, hope you had a good night out.  Just wondering if you have had a chance to have a look at this yet?

It looks to me that in order to properly control our UFH and rads we need to have zones for the two that can be controlled independently, but our heating circuit only has single 2-way valve on it, so either both are on, or both are off.

Thanks,

Peter. 

Posted by: @peterr

@derek-m 

Hi Derek,

Happy New Year, hope you had a good night out.  Just wondering if you have had a chance to have a look at this yet?

It looks to me that in order to properly control our UFH and rads we need to have zones for the two that can be controlled independently, but our heating circuit only has single 2-way valve on it, so either both are on, or both are off.

Thanks,

Peter. 

Hi Peter,

Sorry about my failure to respond, one of the pleasures of growing older, in fact between the two of us, my wife and I can manage to forget everything. 🙄 

At first glance it is obviously not possible to operate your system as envisaged by Mitsubishi, since not all the necessary equipment has been installed, but it may be possible to effect a solution. Could you provide details of all the equipment associated with your UFH.

Posted by: @derek-m

Hi Peter,

Sorry about my failure to respond, one of the pleasures of growing older, in fact between the two of us, my wife and I can manage to forget everything. 🙄 

At first glance it is obviously not possible to operate your system as envisaged by Mitsubishi, since not all the necessary equipment has been installed, but it may be possible to effect a solution. Could you provide details of all the equipment associated with your UFH.

Hi Derek,

No need to apologise, I appreciate your generosity in helping out so many people on this forum.

Our UFH system is quite old (~15 years) and uses a manifold and controller from Uponor.  The main controller is a C-55, with an I-75 Interface Unit.  The system was originally designed with 6 heating zones, but in some cases we have two zones in a single room, so they are linked together in the controller.  Overall we have 3x T-55 thermostats, one for the kitchen, one for the lounge, and one for the hall/dining room (which are linked by a pair of double doors which we leave open most of the time).  The UFH has its own circulating pump which is activated by the C-55 controller.

Hi @peterr

My first question would be, are all the rooms achieving the desired temperature, and if not which ones are failing?

Looking at the details for your Upinor controller, I cannot see a specified output to stop and start your heat pump, unless an interposing relay has been installed. It may be possible to check if this is the case. If possible monitor the water flow and return temperatures. Turn the temperature setting for the radiator zone down, which should cause the heat pump to stop. Turn up one of the thermostats for the UFH, so that it is calling for heat energy, if the heat pump starts then it would appear that there is some form of interface between the UFH controller and the FTC controller. If the heat pump fails to start fairly quickly, then monitor the flow and return temperatures, it could be when they fall sufficiently the heat pump will start due to low water flow temperature. This could take a while dependent upon the capacity of your system.

It could be possible that a buffer tank is incorporated in the bottom section of your hot water cylinder, are there any pipes going to and from this area? What is the manufacturer and model details?

Did you state that there is a further water pump for the radiator circuit, in addition to the one for the UFH?

@derek-m 

Hi Derek,

It is the downstairs rooms that are sometimes a bit colder than desired.  If we turn up the flow temperature to get the downstairs rooms right, then the upstairs becomes too warm.

As far as I can tell there must be some sort of control between the UFH and the FTC.  The heat pump responds to demands for heat from the UFH pretty quickly. I think this is the control that goes in to IN1 on the FTC, although it's little tricky to trace because the wiring is a complete mess!  I have been trying to get this information out of our installer for a while now, but they are not being very cooperative.

We don't have a buffer tank, the cylinder is a Telford Tempest.

There isn't a pump specifically for the radiator circuit.  There is one pump that circulates the flow from the ASHP to either the DHW or the heating circuit, depending upon the setting of the 2x 2-port valves controlled by the FTC.