Ducted chilled water fan coil options

[kevinm]

1 hour ago, JohnMo said:

You run water temperature above dew point, so zero condensation issues.

With a heat pump you run 24/7 at as low flow temp possible to keep house stable - weather compensation. Response time is not a factor. As UFH even in thick screed, responses to outside changes quicker than a well insulated house. Floor temp is so close to room target temp, that changes in room almost self modulate floor output.

 

True. 

 

If you run at above dew point, you wont dehumidify. Also the dew point inside the floor structure is likely to be higher than in a room, especially with steam/humid air rising from the ground floor.

 

Both my wife and I struggle to sleep if the bedroom in our current house is above 22/23C. We want carpet in our bedroom which would render ufh cooling useless.

 

My preference was for ufh cooling starting out, but once I dug into it, fan coils made more sense.

 

EDIT: I should have also said that we are only putting fan coils in bedrooms, kitchen and sitting room.

Edited Wednesday at 13:14 by kevinm

[HughF]

On 25/06/2025 at 13:19, dpmiller said:

a/c linkage is simple startup yep. 

Do you know if dhw still has priority if I use the separate heating and cooling call inputs, instead of the a/c linkage input?

[dpmiller]

59 minutes ago, HughF said:

Do you know if dhw still has priority if I use the separate heating and cooling call inputs, instead of the a/c linkage input?

I'd presume so, but have never tried it

[HughF]

11 hours ago, dpmiller said:

I'd presume so, but have never tried it

I’ll give it a try and report back. Currently drawing up a simple relay based circuit to enable to cooling call when any of the fan coils are switched to ‘fan only’ mode.