Custom made Low Loss Header advice

[Pipedreamer]

Drain off valve is integral and at the bottom of the header. If the lower right hand tapping is to a secondary expansion vessel - why is it at floor level next to the washing machine??

Im not sure i understand your question? Is there an issue with it being there? Unless im missing something obvious

 

[ShaunCorbs]

Drain off valve is integral and at the bottom of the header. If the lower right hand tapping is to a secondary expansion vessel - why is it at floor level next to the washing machine??

Elbowing back to under the boiler at floor level maybe due to size and weight eg not wall mountable etc
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Im not sure i understand your question? Is there an issue with it being there? Unless im missing something obvious

No there isn’t

 

[Pipedreamer]

Times eg x so

1.5 x 0.14 x 4.2 x 20 = 17.6kw

Ahh yeah that so

Elbowing back to under the boiler at floor level maybe due to size and weight eg not wall mountable etc
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No there isn’t

Yes it was a big one i thinl from memory maybe 40 or 50 ltr floor standing one

 

[ShaunCorbs]

Ahh yeah that so

Yes it was a big one i thinl from memory maybe 40 or 50 ltr floor standing one

Just incase you don’t know how to work expansion size out

Either 1l per kw or 1l per rad will get you close enough (over sized)

 

[Pipedreamer]

Times eg x so

1.5 x 0.14 x 4.2 x 20 = 17.6kw

Ahh that seems extremely obvious now you ve pointed it out.

So if my circuits are 28mm would o substitute 28mm figures in tjat calculation for x 3 zones

Then the same for 22mm x 1 zone and then add them together for the figure of the kw of the load?
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Just incase you don’t know how to work expansion size out

Either 1l per kw or 1l per rad will get you close enough (over sized)

Well ive sort of done that ive done 50 ltr vessel for the 50 kw boiler. However they are adding a couple of rads so you reckon upsizing it is wise or overkill?

 

[ShaunCorbs]

Ahh that seems extremely obvious now you ve pointed it out.

So if my circuits are 28mm would o substitute 28mm figures in tjat calculation for x 3 zones

Then the same for 22mm x 1 zone and then add them together for the figure of the kw of the load?

Yes so

Work the flow rates for the single 28mm zone then times by 3 if the same loading or work out the other two if different (flow rate)

Then work out the 22mm zone (flow rate)

Then add all 4 loadings (kw ratings)

That will give you the pump flow rate and header size
[automerge]1574804154[/automerge]

Ahh that seems extremely obvious now you ve pointed it out.

So if my circuits are 28mm would o substitute 28mm figures in tjat calculation for x 3 zones

Then the same for 22mm x 1 zone and then add them together for the figure of the kw of the load?
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Well ive sort of done that ive done 50 ltr vessel for the 50 kw boiler. However they are adding a couple of rads so you reckon upsizing it is wise or overkill?

wise always oversize withing reason no harm in haveing too much expansion other than servicing it

 

[Pipedreamer]

Yes so

Work the flow rates for the single 28mm zone then times by 3 if the same loading or work out the other two if different (flow rate)

Then work out the 22mm zone (flow rate)

Then add all 4 loadings (kw ratings)

That will give you the pump flow rate and header size

How would the 28mm zones be different load?
Would it not be the set amount of figures for each size pipe?

So you said 15mm is 0.14 litres so im assuming its always that figure and likewise the figure for 22mm 28mm and so on ?

Or have i got that wrong?

Yes so

Work the flow rates for the single 28mm zone then times by 3 if the same loading or work out the other two if different (flow rate)

Then work out the 22mm zone (flow rate)

Then add all 4 loadings (kw ratings)

That will give you the pump flow rate and header size
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wise always oversize withing reason no harm in haveing too much expansion other than servicing it

Haha very true
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Also in your original equation whete does the 4.2 come from?

 

[ShaunCorbs]

Header size (diameter) in mm

you first need flow rate l/s

(the flow rate of 60kw Heating system with a delta t of 20degress is
60 / (4.2 * 20) = 0.71 l/s)

From the 60kw above 0.71 l/s

Convert to m3/s so divide by 1000= 0.00071m3/s

Stick in to the following

(0.00071 * 1.28)/0.3, Square root of that = 0.055meters

The 1.28 is constant, the 0.3 is velocity in m/s through the header

0.055 * 1000 = 55mm eg 54mm copper etc
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How would the 28mm zones be different load?
Would it not be the set amount of figures for each size pipe?

So you said 15mm is 0.14 litres so im assuming its always that figure and likewise the figure for 22mm 28mm and so on ?

Or have i got that wrong?

Haha very true
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Also in your original equation whete does the 4.2 come from?

depends if its sized correctly it might be under loaded eg not running at its max always best to size off the load
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4.2 is your SHC (specific heat capacity of the fluid in the pipe) eg specific heat capacity of water and how much to raise it 1dc

 

[Pipedreamer]

Header size (diameter) in mm

you first need flow rate l/s

(the flow rate of 60kw Heating system with a delta t of 20degress is
60 / (4.2 * 20) = 0.71 l/s)

From the 60kw above 0.71 l/s

Convert to m3/s so divide by 1000= 0.00071m3/s

Stick in to the following

(0.00071 * 1.28)/0.3, Square root of that = 0.055meters

The 1.28 is constant, the 0.3 is velocity in m/s through the header

0.055 * 1000 = 55mm eg 54mm copper etc
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depends if its sized correctly it might be under loaded eg not running at its max always best to size off the load

Oh Damn me everytime i think i understand i get confused again. Lol.

So how do you calculate load then?

Im gonba have to sit down and practice these rquations you ve given i think.
For ecample the one you ve given working it out at 55cm is making my head hurt haha

 

[ShaunCorbs]

Oh Damn me everytime i think i understand i get confused again. Lol.

So how do you calculate load then?

Im gonba have to sit down and practice these rquations you ve given i think.
For ecample the one you ve given working it out at 55cm is making my head hurt haha

write it out on a piece of paper and practice its not easy when you look at it but when you break it down its not bad just need a decent calculator just take it step by step

if you just want to size a llh post 23

pump sizing eg each zone / multi zone (flow rates) post 10

 

[Pipedreamer]

When i get time to sit down and practice these and try and work mine put can i pm you my workings see if im Damning it up or not?.

Now confused if im working out the 28mm flow rate or load and how.

Also where did you find the figure for 15mm pipe so i can source figures for 22 and 28mm?

 

[ShaunCorbs]

When i get time to sit down and practice these and try and work mine put can i pm you my workings see if im Damning it up or not?.

Now confused if im working out the 28mm flow rate or load and how.

Also where did you find the figure for 15mm pipe so i can source figures for 22 and 28mm?

its in the gas igem up 1

should be listed below if it works

header size use total kw eg calc in post 23

pipe sizing use post 10

 

[Pipedreamer]

its in the gas igem up 1

should be listed below if it works

Thank you.

Before i try and work this out. Im still unsure of the diffetence between working out the flow rate of the 28mm and working out the load of the 28mm.

What factors mean there is more load? Or is it literally how many rads are off each zone?

 

[ShaunCorbs]

Thank you.

Before i try and work this out. Im still unsure of the diffetence between working out the flow rate of the 28mm and working out the load of the 28mm.

What factors mean there is more load? Or is it literally how many rads are off each zone?

sorry prob confused you a bit with estimated load vs actual load

(forward thinking if you slightly oversize you always have some spare capacity if the customer wants to add some more rads later on off a branch / zone)

for header size you want need to size each zone just the total heat load on the header

 

[Pipedreamer]

sorry prob confused you a bit with estimated load vs actual load

(forward thinking if you slightly oversize you always have some spare capicty if the customer wants to add some more rads later on off a branch / zone)

Haha im definitelt confused but its me not you lol.

If i try and work this oit can i send you a photo and you tell me if im barking up wrong tree or getting it in ball park?