Ecodan Cooling

[xander054]

Hi,

 

I have an Ecodan heat pump model -PUHZ-W85VAA and I was excited to hear it could also do cooling. We have UFH so I believe this is called “slab cooling”?

 

The problem is Mitsubishi said my model was not supported and they weren’t really that helpful in explaining why.

 

I noticed a few of you guys have made it work and wondering if you could share your model numbers and maybe fill me in on why mine doesn’t cool.

 

 

 

 

[joth]

The model doesn't support it, or their technical support doesn't support setups using it?

I expect it's the latter, but their technical support doesn't support me whatever, I can't even buy a buffer tank thermistor from them as I'm not a registered installer.

 

I have the same model as you (I think) and got cooling working very well now. Mostly via fan coil units, but the slab cooling does assist a little too.

There's plenty of threads on here discussing how to do it. Tldr there's a dip switch in the FTC6 to enable it. 

[Gary68]

Hi,

 

They are probably saying that cooling isn't supported as that model of Ecodan was on the RHI scheme where cooling has to be disabled, this is done by changing one of the dip switches on the front of the Ecodan controller.

 

If you have a cylinder with a box on the front like the one in the video below turn off the power to everything unscrew the front panel and move dipswitch SW2-4 from off to on position., then turn everything back on once your main controller boots back up go to the heating options and cooling will now be visible.

 

You will need to activate cooling in the timing schedule as its different for heating and cooling and you will need to turn up your thermostats to a higher than room temperature than its currently at to open the UFH circuits but then chilled water will circulate you can change the water temperature up and down on the main controller.  It works really well with UFH in terms of cooling the house.  When it was 40C last year my downstairs was at 20C constantly.  It doesn't work well with rads and you just get pipes with no appreciable cooling you need fan coils for that to work as discussed on other posts

 

https://www.google.com/search?q=ecodan+dip+switches&rlz=1C1GCEA_enGB995GB995&oq=ecodan+dip+switches&gs_lcrp=EgZjaHJvbWUyBggAEEUYOTIICAEQABgWGB4yCggCEAAYhgMYigUyCggDEAAYhgMYigUyCggEEAAYhgMYigUyCggFEAAYhgMYigXSAQ0yOTQ3ODAxNmowajE1qAIAsAIA&sourceid=chrome&ie=UTF-8#fpstate=ive&vld=cid:5ee4906d,vid:0Y4w18656d0

Edited June 23, 2023 by Gary68