pl. anybody let me know, will there be any major adverse effect if we take 65mm dia chw pipe tapping from 50mm dia..... For 02nos. of AHUwith equal TR are there at site with 65mm dia header & 50mm dia connection for each AHU but tapping has been taken from 50mm dia CHW pipe & connect to 65mm dia header for both AHUs.....water flow is as per requirement at site... This case has already been done at site... i am unsure about any major adverse effect... For safety design, the cooling coil of AHU is 6RD with 2.0m/s coil face velocity....