I have a overheating issue very few days with my boiler when the UFH is on have to reset CH and HW all working perfect. My UFH is polypipe with a Baxi boiler. I have had a baxi engineer out to look at the boiler who has advised that the UFH needs balancing as the heat from boiler is not dispersin. I have also been advised that maybe installing a pipe thermostat on the return flow pipe. I am a complete novice guys. Any help is appreciated. Quick pick of manifold attached.