Loop balancing, constant circulation

Gordy

    When does loop balancing become a mute point if a constant circulation strategy is used instead of an on/off circulation strategy were implemented.



    I guess it will still come in to play since loops if not balanced will see different flow rates, but may not be as noticable of an issue. Talking stricktly radiant here.



    Should loop balancing be done on a design day? If one balances loops for same return temps on a shoulder day (if flow meters are not installed), and since higher heat load loops will be subject to more load at design day will balancing be different?



    Circulator sizing for on/off verses constant strategies. Can a circulator be down sized a bit for a constant flow design verses on/off strategy? Thinking response time being different for on/off verses constant where high load loops end up cooling more than low load loops between calls. Thus taking those higher load loops more time to get up to temp. Again this is where constant circ eliminates the higher load loops from excessive cooling. Everything stays same same temps loop to loop all though this could cause cooling in the lower load loops everything stays balanced.





Then again maybe I'm over thinking this??



Gordy













 

icesailor

Thinking:

If the customer is happy and satisfied, you are over thinking the situation.

If it ain't broke, don't try to fix it. It will cost you time and money

Gordy

Efficiency

  Ice Sailor, this is hypothetica., Could apply to new, and old systems. Thinking about the most effcient way to provide the best comfort efficiently for the best total system efficiency....... moving the water can cost some watts





Gordy 

icesailor

Efficiency:

In search of efficiency, one must be careful to spend $10.00 to save a dime.

Whenever I give my customers a choice, they seem to always want to spend the dime and not the $10,00.

Or another way, if I give them choices, what will get then by, something better and the whole nine yards, the go with the basics or a little more. If I only quote the whole nine yards, they go with scorched air/AC. The HVAC contractor goes with 90% gas, fiberglass duct board with round flex duct. If they go hydro-air, they will supply the boiler and indirect, get some slug to do the water piping. Someone else will do the gas piping, and when they don't have enough hot water, they call me.

It's amazing how much money you can save by doing it wrong the first time.

Harvey Ramer

I have found that loop balancing ( especially on large manifolds)

only holds true at a fixed supply gpm and pressure. For Instance, a 3 speed circ on a 10 loop manifold. When you balance the loops and then change the speed of the circ it messes it all up. If you are thinking constant circulation with trv's I would put a simple copper manifold at every room. If you keep the loop lengths within 10% and cross plumb the supply and return of the manifold it will balance nicely at any gpm the trv allows through.

furnacefigher15

Smaller pump

If you want to use a smaller pump, use a shorter loop.



I would say no downsizing for constant flow, unless the pump in existence is too big to begin with.