# Variable output circulators. Delta-P vs. Delta-T

### Re: Variable output circulators. Delta-P vs. Delta-T

OK, that was pretty much useless. Taco's response was only that the regimen of 3 minutes of running at full speed every time the circulator starts up is fixed into the programming of the Bumblebee and can't be changed by anyone. It is necessary to get past the cold water surge period. They did not address any of my concerns regarding this, but rather they only addressed my inquiry as to whether this 3 minutes could be reduced by the end user to 1 minute.

Sting, you're on!
lsayre

Stoker Coal Boiler: AHS S130 Coal Gun
Coal Size/Type: Stockton Anthracite Pea
Other Heating: Resistance Boiler (13.5 KW)

### Re: Variable output circulators. Delta-P vs. Delta-T

I came across a different formula which states that:
BTUH = k (Delta-P)^0.5 x Delta-T x 500
(where k is a constant called the 'flow coefficient')

I will re-state the equation which I stated earlier in this thread:
GPM = BTUH/( 500 x Delta-T)

If rearranged, this earlier and more simplistic equation becomes:
BTUH = GPM x 500 x Delta-T

From this it can be seen that for the two formulas to be equivalent (as they must):
GPM = k (Delta-P)^0.5

And it can also be concluded that the earlier formula is merely a simplified version of the more complete equation which states that:
BTUH = k (Delta-P)^0.5 x Delta-T x 500

It seems that Taco is not quite telling the entire truth when they state that Delta-P is nowhere to be found in what they refer to as the "universal hydronics formula". Where they have it right is that Delta-T remains as an integral part of the expanded equation, and a pump that is not watching Delta-T and thereby modulating Delta-P (which is how the Bumblebee obviously works) is still in some way missing the boat (or flying blind).
lsayre

Stoker Coal Boiler: AHS S130 Coal Gun
Coal Size/Type: Stockton Anthracite Pea
Other Heating: Resistance Boiler (13.5 KW)

### Re: Variable output circulators. Delta-P vs. Delta-T

So it seems that for variable output pumps (like the Alpha or the Bumblebee) they can either fly blind (totally oblivious to Delta-T, as for the Alpha) or they can monitor and face Delta-T head on (as for the Bumblebee) and thereby get trapped into the problem of how to manage some seriously cold water potentially flowing at circulator start-up. One compromises at all times, and one compromises for 3 minutes at each start cycle. Which is better?

Would the ultimate solution be a circulator that responds blindly to Delta-P (only) for the first 3 minutes and then switches over to Delta-T mode? Taco, are you listening? This seems like a better solution than arbitrarily running full out for the first 3 minutes.
lsayre

Stoker Coal Boiler: AHS S130 Coal Gun
Coal Size/Type: Stockton Anthracite Pea
Other Heating: Resistance Boiler (13.5 KW)

### Re: Variable output circulators. Delta-P vs. Delta-T

These type of pumps may require some rethinking when it comes to designing a piping system layout.
McGiever

Stoker Coal Boiler: AXEMAN-ANDERSON 130 "1959"
Hot Air Coal Stoker Stove: HARMAN MAGNUM
Hand Fed Coal Stove: RADIANT HOME AIR BLAST
Baseburners & Antiques: OUR GLENWOOD 111 BASEBURNER "1908"
Coal Size/Type: PEA / ANTHRACITE, NUT-STOVE / ANTHRACITE
Other Heating: Ground Source Heat Pump
Stove/Furnace Make: Hydro Heat /Mega Tek

### Re: Variable output circulators. Delta-P vs. Delta-T

Atlas to the world --- stay up there I am getting tired

Lets revisit the fact that you are moving energy [stored in the coal] from the conversion source [ the boiler] to your comfort [ the load]

Then let me get you past the fact that you are NOT pumping water because as above --->you are moving energy

or think of this as circulating energy

so ---you are employing a [ or several] circulator(s) NOT a PUMP

if you were pumping you would be creating pressure and your not creating that - the wet system is UNDER pressure or atmospheres of weight - remember if you have and air bubble in the supply or return line - even just a small one at the top of the pipe loop - your "circulator" will not function because is does not create any pressure to force the bubble out of blocking the flow it wants to make.

Ok That written ----
Now think of my analogies regarding the similarity of a a vacuum cleaner motor and your circulators = when you plug the vac hose the vac motor does what???? it speeds up right because it is not moving air and it is operating under almost non load.
Take that thought - and apply it to your "new"pump running full out for the first three minutes - SO WHAT??? it is simply moving or circulating as much energy bearing liquid in relation to the number of open zone valves - if only one zone valve is open at the time - the circulator is not creating a tsunami into that zone --- so it runs for three minutes and then begins to process - It has to because if it didn't purge the zone it would be running forever too slow to satisfy the zone - it has to see a correct return temperature before it can supply a correct supply temp

Think of the work the circulator is doing in regard to System Balance of improper installed loops and choking flow on the SUPPLY side of the circulator - if you choke too much all that happens is the load will not see any energy bearing liquid and the pump runs happy ever after - under almost NO load.

your "circulator' works as necessary to supply one or all demands - is works [ if you could measure amp draw ] - up to demand - and only loafs when demand is low - This appears to be the opposite of what i think your thinking

but then what was I thinking when I started writing all this drivel - try this circulator on for size once and see if it chafes???
Sting

Other Heating: OBSO Lennox Pulse "Air Scorcher" burning NG

### Re: Variable output circulators. Delta-P vs. Delta-T

lsayre

Stoker Coal Boiler: AHS S130 Coal Gun
Coal Size/Type: Stockton Anthracite Pea
Other Heating: Resistance Boiler (13.5 KW)

### Re: Variable output circulators. Delta-P vs. Delta-T

?
Sting

Other Heating: OBSO Lennox Pulse "Air Scorcher" burning NG

### Re: Variable output circulators. Delta-P vs. Delta-T

Sting wrote:

?

I was in this thread by mistake while typing something for the "Life beyond the Physical" thread. It would not have been a good fit here.
lsayre

Stoker Coal Boiler: AHS S130 Coal Gun
Coal Size/Type: Stockton Anthracite Pea
Other Heating: Resistance Boiler (13.5 KW)

### Re: Variable output circulators. Delta-P vs. Delta-T

Have you guys seen video of the Monkey attempting to fornicate with a football????? Sting, you slay me!!!!!!!!!!!!!!!!!!!!!!

Try it, you'll like it..............What ever happened to KEEP IT SIMPLE STUPID????????????????????????????????????????
whistlenut

Stoker Coal Boiler: AA130's,260's, AHS130&260's,EFM900,GJ & V-Wert
Hand Fed Coal Boiler: Franks,Itasca 415,Jensen, NYer 130,Van Wert
Hot Air Coal Stoker Furnace: Alaska, EFM, Keystoker, Yellow Flame
Hot Air Coal Stoker Stove: Alaska, Keystoker-2,Leisure Line
Hand Fed Coal Stove: Alaska, Gibraltar, Keystone,Vc Vigilant 2
Hand Fed Coal Furnace: Ford, Jensen, NYer, Van Wert,
Baseburners & Antiques: Glenwoods
Coal Size/Type: Barley, Buck, Rice ,Nut, Stove
Other Heating: Oil HWBB

### Re: Variable output circulators. Delta-P vs. Delta-T

April Fool
Sting

Other Heating: OBSO Lennox Pulse "Air Scorcher" burning NG