My plumber has installed underfloor heating in my home connecting it to my existing heating and hot water system. We have a system boiler on the ground floor with the boiler pump for the existing heating and hot water located in the airing cupboard on the first floor. My plumber has teed off the flow directly above the boiler ie. between the boiler and the boiler pump is this normal, should this work? It seems to me (I am not a plumber so may well be talking ****!) that teeing off before the pump means there is now negative/no flow (not pressure) in that section of pipework. I have included 2 images to illustrate the different approaches. My existing heating and hot water still work fine but something isnt working in the underfloor heating and it seems to not be circulating warm water. The underfloor heating system has been dismantled with no obvious errors.