Andrew D

Thanks @Redbeard, I had wondered about the bit on the RHS, maybe that could be replaced with a stronger column? I had also wondered about something like the following where a beam could be supported by the wall to the right and extend across to the new opening. This could be at the right height to be just above the top of the tumble dryer.

Our cellar stairs are made of york stone and are built in between our neighbour's wall and a single story brick wall from our cellar floor level to the bottom of the suspended ground floor joist level. Above this is wooden panelling to hide the cellar stairs from the hall so apart from the stone cellar stairs this wall isn't supporting anything else. Even the ground floor hallway joists run parallel to the wall so aren't supported by it. The wall only runs for the length of the stairs with an opening beneath the top of the stairs between this wall and a supporting wall running perpendicular to it. See the photo where you can see the edge of the stone steps set in the brick wall. I want to put a tumble dryer where the current opening is but this makes the rest of the space under the stairs a bit useless as I won’t be able to get to it. so I’d like to create an opening in this part while still supporting the stairs. Something like my attached sketch. Does anyone know a simple way of doing this? What support would be required? Thanks in advance and apologies for the messy cellar

Yes I have the same versions as you since the summer. I appear to be getting better COPs than this time last year but I have improved a number of things since then. I'm reserving judgment until we've been through a bit of winter so I can do a more fare comparison. Especially to see if it's better at getting into and maintaining long runs in colder weather. With the old firmware last year there were lots of times where it looked like it should be able to maintain a long run but would randomly ramp up overshoot and stop.

Do you know what versions you have? You can find this out by going to the Installer Settings and Running Information. Then using the codes 90 and 91 you get the major and minor versions for the outdoor unit and 190 and 191 give you them for the FTC. What behaviour changes have you noticed?

Yea, It looks like it realises the flow temperature is getting too high (because emitters are unable to get rid of the heat quick enough) and so does one last blast, often increasing input power a bit. This then results in it being a bit longer before the next cycle. I think this is probably based on it learning how your room temperature reacts to this so if doing this doesn't make much difference to how stable the room temp is it probably does it more but if it was having an impact it might not do it so much and allow more cycles. The FTC6 controller allows you to configure limits on the amount of over and undershoot to allow as well as a responsiveness time that can be adjusted to account for different types of emitters, like radiators being fast responding and UFH being slower. Frustratingly there is no way to configure the over and undershoot when in Weather Compensation mode. This makes it fairly inefficient unless your emitters are sized appropriately and there is enough heat loss due to low outdoor temps. This is all based on my assumptions watching what it does.

I have an Ecodan PUZ-WM85VAA. I have this in Auto Adapt mode which uses indoor temperature, I believe combined with knowing the outdoor temperature, to learn what flow temperature to use. This allows the flow to overshoot a bit more to allow a longer off period. This is much better than the Weather Compensation mode which tries to too tightly stick to the flow temp on the curve and doesn't have the ability to be configured to allow for a bit more over and undershoot to minimise this. This causes lots of cycles in shoulder months and on systems where radiators are undersized. The Ecodan will keep the system pump on constantly between cycles, I guess so it can monitor the flow and return temperatures. My pump's speed can be controlled by PWM so I have an ESP32 running esphome connected up to this to reduce the flow rate to a minimum between cycles to save energy. Then when the heat pump's compressor is running the flow rate is increased and increased further for DHW. I've also experimented with trying to use the pump speed to hit a delta T of 5K but this doesn't seem to improve things noticeably.

Anyone any experience of Jaga Briza High performance fan convectors and fan coil units for heating and cooling (jaga.co.uk) They do wall and concealed versions that can be connected in different ways. Also have very good outputs for the larger ones. No pricing though so I assume they could be pricy.

I'm considering installing a concealed fan coil unit behind a kneel wall in our attic landing for heating and occasional cooling when blinds and night purging aren't enough. I want to run dedicated flow and returns back to the cellar where our system pump, 3 port valve etc are. My reason for not just teeing off existing rad pipes is that I want to have these well insulated for the full length to allow water to be below the due point and so I can have a valve that isolates the rest of the system when in cooling mode. In an ideal world I'd use copper and insulate with a closed cell insulation like Armaflex. However there are places where I need to run through solid joists and other places where I need to push/ pull the pipe between joists. So I'm not sure that approach will be practical. Does anyone have any tips for how to do this? Is there any pre-insulated pipe that would make this easier?