Advice needed turning on ufh with anhydrite screed

[stusgsx]

Hi u lot.
I tiled 100 odd sqm of 450x900 porcelain onto anhydrite screed which has a water ufh system. It's all been commissioned before tiling and the screed tested. I have been told the ufh can not be turned on gradually as it's lowest setting is 30 degrees C (water temp) so I'm worrying that it is going to cause problems going from about 5 degrees now to 20-25 floor temp.
Tiles have been down for 3 weeks now and I fixed with gypsum based addy.

Any advice would be great. If it pops or cracks the tiles is it still going to be down to me even though they can't turn it on gradually?
Thanks

 

[Ajax123]

30 degrees flow temperature us about the norm for most manifolds. If they turn it on at that they will get a surface temperature of around 22 degrees. Not sure if that helps as I understand your concern but I have never seen tiles pop as a result of warming where gypsum adhesive was used.

 

[stusgsx]

Ok thanks for that. They are going to leave it off for now anyway as the house is still a way off getting finished

 

[newlineuk]

How long has the slab been down for, as it could take a while for that to dry out. Hopefully when they commissioned it they left it on to push moisture out.

 

[stusgsx]

It was down for about 10 months then heating left on for a month or so then I tested it over a week and it was down to 35% RH

 

[newlineuk]

It was down for about 10 months then heating left on for a month or so then I tested it over a week and it was down to 35% RH

What did you test it with?

 

[stusgsx]

2x digital hygrometers glued to the floor