Boiler Circuit Flow Rate

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Absent any useful information, I'd say 20 GPM.
The main point is, does ti work?

What color is the house?

In addition to this, can you tell us if the loop contains anything that might radiate some of the heat and what flow resistance is encountered at each appliance.

I think his wife has occupied his body and taken over his mind, and can't figure out how to turn the heat up.

Maybe it will pass.

Lyn's estimate sounds reasonable, maybe somewhat less on account of the long run. I don't have any data here at home, so I'll try for better tomorrow.

All of my old reference books got packed up into random boxes and put out in the shop so I did not bother with spending the time to find them and dig them out.

What useful info do you need besides pipe material, diameter, length of run and available head pressure based on pump min and max numbers for feet of head Vs flow?

Yes its heating the house well! At present the average air temp directly off the furnace is 146 F on boiler heat. The normal propane burner runs about 130 F so I am getting at least 85K BTU's off the hot water system!

The house is now set at 72 F instead of 68 F so the old hen is happier now.

I was just curious as to what my approximate in pipe flow rates were with the new dual pump system running that long of line set.

My guess was 10 - 12 GPM given my duct heat temps.

Wives, ya gotta love 'em! (Cause if you didn't you'd probably want to kill 'em)

Cowboy: What is the similarity of a cowgirl and a pistol?

Cowgirl: I don't know.

Cowboy: If you got one, sooner or later you're gonna want to shoot it!

Might be time for a vessel of known capacity and a timing device of some sort...

Bucket and stopwatch?

I have an inline digital flow meter that would tell me exactly but unfortunately all of my connections are now done in solid crimp so it's not so easy to unhook and do a live test at any point in the system.

I could do a test but it would be a big inconvenience to do the unhook test and re hook off of the line going out of the shop wall at this point being its now 0 f and 30 MPH winds outside.

Its not that critical of test anyway. I did some rough estimates on my TI Voyage calculator and it says I should have around 9 - 11 GPM depending on rough estimates for the variables.

I should have around 9 - 11 GPM ...

TcmTech, your pair of pumps push-pulling a path of 650 feet of 1" Pex pipe won't ever obtain a flow rate that high. Pressure drop at 8 GPM is already 55 Feet-H2O. At 9 GPM it's away over the top at 68 Feet-H2O.

I'll stand by my guesstimate ( reply #11 ): 4 GPM

Good luck and keep warm.

Well whatever it worked itself out to be it keeps the house warm so it's good enough!

If you have a clamp-on amp probe and the pump curve, you should be able to determine the flow rate.

Good point! I suspect that the load may NOT be equally distributed between the two pumps, depending on tubing sizes, number of elbows, etc. in the boiler, distribution system, and radiators. If so, it may be necessary to measure both pumps and average them

Assuming 650 feet straight run of 1" pipe, PDs from a PEX tech sheet are:

The system curve ought to intersect your pump-pair combined curve at around 4 GPM.

Well what ever the flow rate is its keeping the house nice and warm so its good enough!

Every one of those statements is incorrect.

This is so laughable that I can only hope that you are kidding.

"40 gpm each at 60 feet head each" Wrong!

"40*2 =80 gpm at 120 feet head" Wrong

"Your head is assumed as 650feet" Wrong!

"you will get a head of 120 feet" Wrong!

"Answer will be 80gpm at 120 head" Wrong!

"your present head is only 65" Wrong!

"flow rate will be 97.5 gpm.(120/80=1.5*65)" Wrong!

"then flow rate will be 78 gpm. Wrong!

You may be close on the efficiency.

Not even on that, because that is not what pump efficiency is.

Yeah, it's not worth trying to explain to this one.

Ah-HA! NOW I can see the viability of an energy barge...

No, wait... never mind. It (an energy barge) still won't work even with your help.

[edit] Never mind. I see that, except where you said "You have 2 pumps..." it has been already pointed out that every point of your entire comment is incorrect.

Is this thread suffering from some sort of forum quantum instability?

It keeps drifting in and out of the main page! Just when I think it's faded out for the last time it comes back.

Do I need to do a recap of my boiler system layout so some can get their minds around my DR frankenstein's heating system?

Just explain the independent ethanol circuit and condenser....

Oh, come on!

Nobody gives a rat's butt about your boiler any more.

We've degraded into the typical discussion here. This!!. No, this! No, you're wrong, it's this.

One thing we can all agree on is that Milhan knows nothing about the subject.

Hey I care about my boiler! It keeps the house borderline uncomfortably warm which gives my wife one less thing to complain about and me one more reason to leave the house at any moment without having an actual real justified reason to.

So, you're handy with stuff.

Dummy up some thermometers to read about 5 degrees high and place then throughout the house. Then, adjust the temperature back down so that she won't be too hot.

What makes you so sure I didn't already?

Did I mention I also put a soft plug heater cord on my pickup so it starts better for her when she goes to work?

I may have to put cord on her car next.

For a follow up I figured it out. I had to check the first pump that comes right off the boiler for a possible clogged impeller today so I injected a slug of air into the feed line to push the water down the line about 5 feet so I could work on a dry pump.

After checking the pump I turned the feed valve on and let the pump prime for a few seconds then opened the return valve so the system could flow normally. FRom that I timed the air bubbles round trip and it took 117 seconds.

Given the roughly 20 gallons of total circuit volume that puts my flow rate at just a hair over 10 GPM!