Yes, this is true but there are some combi's with a 22mm connection but the main thing is if your hot water pipework works out to be greater than 15mm, you should want to think about a unvented cylinder not a combi. But if your not worried about it then you can fit a combi with a 15mm pipework and live with the pressure loss around the home. Remember this is a guide not a regulation, its the designers choice in the end.
That is a very good question, it's all about the outlets (taps , showers, WC's, sizes and how many of them) some have 15mm connections, others 22mm. They also have different requirements, some modern systems need 28mm pipework at the start of the run to work correctly. This is why we do the maths, this is the easier one to use, does not take long to do and check what a system needs. Taking your time and getting it right makes the different between a cowboy, a good plumber and a great one in my book.😋
These are great. Can you do a similar version for radiator runs please?
Thank you for your support. I am working on think's at the min and there will be heating design coming.
hi, all combi boiler comes with 15mm (1/2") connections for hot and cold water.
Yes, this is true but there are some combi's with a 22mm connection but the main thing is if your hot water pipework works out to be greater than 15mm, you should want to think about a unvented cylinder not a combi. But if your not worried about it then you can fit a combi with a 15mm pipework and live with the pressure loss around the home. Remember this is a guide not a regulation, its the designers choice in the end.
Why not in every situation just use 22mm for water services feeds to save having to calculate
That is a very good question, it's all about the outlets (taps , showers, WC's, sizes and how many of them) some have 15mm connections, others 22mm. They also have different requirements, some modern systems need 28mm pipework at the start of the run to work correctly. This is why we do the maths, this is the easier one to use, does not take long to do and check what a system needs. Taking your time and getting it right makes the different between a cowboy, a good plumber and a great one in my book.😋
Keep up the awesome work! You really need P-R-O-M-O-S-M!
Thanks! Will do!