Low loss header design mistakes

Home radiator heat not bothered how fast the water flows,in, out T1 T2 hotter coming out than going in how is this possible Ti 37c. T2 40c no other means of heating.

Hi Andrew, extremely informative video. I have a question on a site we currently have a horizontal LLH which have primary pumps feeding it, we then have 3 outputs feeding AHU's, radiators and UFH. My question is contractors have recently install a new section to the LLH but they've tapped off each end of the LLH would that have a impact to the balancing of the existing LLH

Could you do an example of that formula please? Struggling with the square root.

What is the unit of ID in the equation?? mm or cm
Thank you.

Very well explained.👍 Thank you.

Brilliant explanation!

Thanks very much. Have been looking for a explanation that makes sense. Cheers.

Hi Andrew can I pick your brains for a minute if I have 2 x 60 kw boilers feeding onto a low loss header what size should my primary pumps be for the 2 boilers thanks as been told a 15/50 will be fine but seems to small to me

Hi mate been watching your channel your knowledge I have a strange 1 for you I have just fitted a ideal evomax 150 kW with single low loss headed primary pump on the return and secondary on flows one for a ahu heater coil and the other a hot water cylinder the flow would only go down the primary flow to header over heat boiler and cut out if I turn secondary pumps off it will flow round header and back to boiler turn them on the secondary flow would only get up to about 35c and would over heat the primary flow but primary return cold I have since removed header and the system works fine but can't figure out why it did not work as have used this set up before on evomax 60kw and all worked fine

Thank Andrew; great not just to see a explanation how the low loss header works but also pointers at how to confirm the maths behind it.

Great video, I have a question your first drawing why can you not just alternate the connections on the secondary side; If you number the connections from top to bottom 1 to 6, so you use flow 1 and return 4 for circuit one, flow 2 and return 5 for circuit two, flow 3 and return 6, would this not counter balance the middle circuit staying in static loop. Would be very interested to see your opinion.

Wow thanks a lot

Suddenly, it all makes sense.
Thank you.
And thanks for telling us what low loss means, no one else bothers to say that.
Well done.

Very interesting Andrew, I have a question though.
With the 3 circuits all set up on the secondary side, pumping & flowing, if one pump is satisfied & shuts down, doesn’t this affect the flow rates of the other two circuits? Thanks, Rus.

Hi Andrew,
What was the book you mentioned in this article?
Cheers
Jase..

Informative and to the point . Thanks for you efforts.

so inside the low loss header unit there are no baffles or anything? I havent worked with these before, very interesting though.

This is a first rate video Andrew, its technical but easy to understand, thanks for taking the time to put it up its much appreciated, I've always wanted to have a greater understanding of low loss headers but it's been hard to find good information until now.

thanks for the video. It would be good to see impact distribution of heat during the flow distribution ?

Fantastic video Andrew. You’ve said .3 m/s in LLH, .5 in distribution header. What would you want in the primary header if you were cascading 2 or more boilers, to ensure the load was split evenly between the two boilers?

Thank you Andrew very informative

Really love your videos Andrew ! Joined Facebook so I can join your forum but having trouble finding you 🙈 I am just search Andrew Millward..