@ashp-bobba If it is not possible in cascade to have 1 unit doing UFH & pool and one doing DHW + UFH / pool when not doing DHW, then plan B is to have the installers move to 2 individual controllers, but keep the plumbing as is. ASHP 1 will start adding to the UFH / pool circuit , and I am thinking if the return flow is still around the 6 degree delta, then the pumps will simply not have to raise the temp so much, but at least when DHW is being heated I get to keep everything else running.

@fosterl2 as far as I am aware it is not possible to do that when they are joined as a cascade unless you connect them as individual systems and design the circuits to act as a 28kW system. But it is worth asking Mitsi as this is something I have never tried to do, all the cascade we have done is due to needing a larger capacity system and not a run and standby system.

Posted by: @fosterl2

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@ashp-bobba If it is not possible in cascade to have 1 unit doing UFH & pool and one doing DHW + UFH / pool when not doing DHW, then plan B is to have the installers move to 2 individual controllers, but keep the plumbing as is. ASHP 1 will start adding to the UFH / pool circuit , and I am thinking if the return flow is still around the 6 degree delta, then the pumps will simply not have to raise the temp so much, but at least when DHW is being heated I get to keep everything else running.

This set up is sound, just be sure to set them up so they match each other when running in 28kW heating mode.

Posted by: @ashp-bobba

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Posted by: @fosterl2

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@ashp-bobba If it is not possible in cascade to have 1 unit doing UFH & pool and one doing DHW + UFH / pool when not doing DHW, then plan B is to have the installers move to 2 individual controllers, but keep the plumbing as is. ASHP 1 will start adding to the UFH / pool circuit , and I am thinking if the return flow is still around the 6 degree delta, then the pumps will simply not have to raise the temp so much, but at least when DHW is being heated I get to keep everything else running.

This set up is sound, just be sure to set them up so they match each other when running in 28kW heating mode.

Are you saying "Plan B" is sound, i.e. separate the two, but just make sure the settings of both individual units match, or the cascade is sound?

If it did not take such a long time to heat DHW, I would stick with the cascade, but I can see from the data that there will be long periods where the UFH and pool will not get any heat.

I have found the pump speed setting and one for tank volume in the set up manual, so plan to see what thy are set for today.

Posted by: @f1p

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@fosterl2

I will ask around about the dip switch for ASHP 2

 

WRT tank, how does the frequency compare? 
Looks like your graph is just from one of the temperature sensors (some have upper & lower fitted) - i would question with that consumption and tank size if 55C and 3x heats per day are required.
We do 1x heat to 47 of the full 250li per day and it covers washing up, 2 showers + kids bath per day

I believe there is a single sensor mid-tank - this is the label on the tank

This is yesterday's daily graph from MELCloud

Posted by: @fosterl2

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Posted by: @ashp-bobba

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Posted by: @fosterl2

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@ashp-bobba If it is not possible in cascade to have 1 unit doing UFH & pool and one doing DHW + UFH / pool when not doing DHW, then plan B is to have the installers move to 2 individual controllers, but keep the plumbing as is. ASHP 1 will start adding to the UFH / pool circuit , and I am thinking if the return flow is still around the 6 degree delta, then the pumps will simply not have to raise the temp so much, but at least when DHW is being heated I get to keep everything else running.

This set up is sound, just be sure to set them up so they match each other when running in 28kW heating mode.

Are you saying "Plan B" is sound, i.e. separate the two, but just make sure the settings of both individual units match, or the cascade is sound?

If it did not take such a long time to heat DHW, I would stick with the cascade, but I can see from the data that there will be long periods where the UFH and pool will not get any heat.

I have found the pump speed setting and one for tank volume in the set up manual, so plan to see what thy are set for today.

 

Yes provided it is piped correctly and you can match the controls to prevent one system running alone for to long on the main heating function.

I looked at the dip switches on the FTC 7s today. On my units, they are tiny rocker switches, rather than slide up / down. Is the dip switch "on" when pressed down on the side where it says on?

@fosterl2 

It's the white points to the side with ON
I presume that Home Assistant project you screenshot earlier would tell you the current positions as i can tell which one i think you are running

Posted by: @f1p

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@fosterl2 

It's the white points to the side with ON
I presume that Home Assistant project you screenshot earlier would tell you the current positions as i can tell which one i think you are running

So, if the rocker is down at the ON side and up on the OFF side, it is ON?

Yes I do have Home Assistant, but it is using the MELCloud integration to gather stats, so nothing shown with regards to any FTC DIP sw settings.

@fosterl2 Ah okay, i make adapters you can get data locally into HA, including from your individual cascades
They would report the current dip-switch status'

Down to the side marked ON is ON

Posted by: @f1p

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Down to the side marked ON is ON

I am pretty sure that on mine, they are set the other way - the ones that are supposed to be ON have the sticking up bit up at ON side, and are pressed down at the OFF side... I did take a photo, but the detail is not good enough to really tell. I'll check again.

@fosterl2 SW 2 looks all "OFF" to me and SW 1 looks all "ON"
They don't look like rockers, they look to be sliders like mine

Reminder that a full power down at the breaker and restart is required for dip switch settings to take effect