How About a Clamp On Ultrasonic Flow Meter for $400?
- Thread starter velvetfoot
- Start date
-
Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.
We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.
We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil. -
Super Cedar firestarters 30% discount Use code Hearth2024 Click here
- Status
Not portable. Could take numerous readings, balance system, and sell it. Just a concept. I'm just googling flow meter.
Flow balance valves and a differential pressure gauge. Flow balance valves are cheap but obviously are not portable.
Watts makes good ones
broken link removed to http://www.ebay.com/itm/like/301050189906?lpid=82)
Watts makes good ones
broken link removed to http://www.ebay.com/itm/like/301050189906?lpid=82)
Last edited:
A pump like the alpha provides pressure and flow information, but it can't be trusted. Another pump I've been looking at, the ecocirc, does not have any readout at all. I guess for multi zone valves supplied by one pump, balancing becomes meaningful since you want the same flowrates through each zone (?). But I'm thinking, for me, two or three circs and two boiler pumps. Would I conceivably have to use 5 of these things to dial it in?
Dp across a pump with power drawn is a very trusted way to gauge flow through a centrifugal pump. The pump curves are well known to the manufacturer and those curves can be mapped in the processor to give a read out.
As far as balancing valves go, you can put several in your system... but it might be a waste of time and money. My main zone at 1gpm and 3gpm doesn't seem to put out any different heat. Looking at the btu rating chart for the baseboard confirms the small difference.
You can hand throttle valve for what "feels" right, or go through the process of measuring dp across your zone and calculating head loss in the pipes/fittings to get flow rate too.
As far as balancing valves go, you can put several in your system... but it might be a waste of time and money. My main zone at 1gpm and 3gpm doesn't seem to put out any different heat. Looking at the btu rating chart for the baseboard confirms the small difference.
You can hand throttle valve for what "feels" right, or go through the process of measuring dp across your zone and calculating head loss in the pipes/fittings to get flow rate too.
Yeah, since resistance increases in proportion to gpm to the 1.75 power (IIRC), it seems like in most cases all circuits will get enough flow, especially since like you say, going from 1 gpm to 3 gpm makes so little difference.
If it looks like a balancing valve might be needed I would suggest merely arranging things such that there would be a place to insert the balancing valve if it ever came to that.
That's true, but we want to use minimum electric energy, so why pump needlessly high? Once the pumps are dialed in, I believe in my case with pumps only and no zone valves, future intervention would be unnecessary, so perhaps an temporary ultrasonic flow sensor, could provide a solution.
Those clamp-ons are very accurate when configured properly, but you need a straight run of pipe with no bends or features, something like 20 diameters before and ten after, IIRC. Check out rental prices, I believe I've rented them for work for much less than $400, but since the client was paying, I didn't pay too much attention.
TE
TE
Just set the pump on the lowest setting and in the highly unlikely event that that's not enough flow to keep the zone at setpoint, nudge it up a setting. But first sharpen your pencil and figure out how long it would take to earn back $400 by tuning a pump burn 12 watts as opposed to 16 watts!
This'd be a good candidate for renting because of the one time use nature.
There are also the boiler pumps, which maybe need a little more accuracy for satisfying mfr's requirements rather than trial and error, but I don't really know. Maybe I can use thermometers on supply and return and come to a conclusion or two.
PassionForFire&Water
Minister of Fire
You can borrow ours to dial in your system (they are calibrated) : Dynasonic, or Omega engineering is selling them under their name.
They are clamp on, 3/4" and 1" copper piping
The ultrasonic clamp on needs a "coupling" medium to make the sound signal travel in the proper way.
It looks like Vaseline or silicone and is expensive
This coupling medium works well for a couple of hours and then it is game over.
I recommend using a Caleffi Quicksetter 135
They are clamp on, 3/4" and 1" copper piping
The ultrasonic clamp on needs a "coupling" medium to make the sound signal travel in the proper way.
It looks like Vaseline or silicone and is expensive
This coupling medium works well for a couple of hours and then it is game over.
I recommend using a Caleffi Quicksetter 135
maple1
Minister of Fire
I have one Alpha pump, and 5 zone valves. Each zone valve has ball valves on either side for easier replacement. I've got all the ball valves set about half way closed, and the Alpha on lowest dP setting - even though I know it's not recommeneded to throttle flow with ball valves, there's not a lot of flow going through with the pump on low. I've got them set to not quite closed enough to create any noise. That was done to try to get my return temps as low as I could, as easily as I could. I also have temp guages here I haven't got installed yet, one will be on system supply & one on system return. I could use those guages to tune in my ball valves further, trying to get to a certain dT in each zone, if my interest holds long enough - I've got all kinds of 'almost done' projects lying around here...
You set up your system identical to mine, temp gauges and all. I never bothered throttling my return ball valves though.
BTW, its perfectly acceptable to throttle with ball valves, especially with such low velocities and dp's as a hydronic system. Any throttled valve/increase in velocity will increase noise as water flow becomes more turbulent.
I am in the process of checking out price and availability for thermal flow meters that are used on district heating systems in Europe. I think they may be a very accurate relatively low cost way to measure flow as they are mass produced for utility service. They are basically a flowmeter with two thermocouples and a brain to convert the inputs to btus per hour but the cut sheets I have seen, there are outputs for flow. There are several companies selling them in Europe but when I call the US reps they don't stock them as there isn't a demand.
PassionForFire&Water
Minister of Fire
![[Hearth.com] How About a Clamp On Ultrasonic Flow Meter for $400?](/talk/proxy.php?image=http%3A%2F%2Fwww.caleffi.com%2Fsites%2Fdefault%2Ffiles%2Ffile%2F132558afc.jpg&hash=3aa87525da855f3939c8675d153ee703 "[Hearth.com] How About a Clamp On Ultrasonic Flow Meter for $400?")
Yep, exactly.
I'm not following this thread closely but I cannot understand why flow is even a concern and you would be looking at circuit setters.
Circuit setters would be applied for a long distribution loop with multiple remote taps of the distribution loop to the loads. There will be a pressure drop along the distribution loop and the circuit setter would be at the tap point to equalize flow to the loads.
The application VF is describing, a long residential loop of baseboard convectors, zoned per floor?, with no remote taps, the concern would be varying supply water temp with demand and delta T along the loop. You would want enough flow so delta T is not huge at the end of the loop, overheating the early convectors and under heating the end loop convectors. I don't see how you can trade flow control for supply water temp control in this application.
I would suggest the long series loop of baseboards is an application for hot water reset. Primary secondary pumping, primary boiler loop, secondary OAT reset load loop with a VS reset injection pump or three way valve between the primary and secondary loops. Pumping into the zone loads, the VS Alpha and zone valves should be appropriate, you could probably use the Bumblebee with fixed delta T across the loop also. There is no concern of flow and fixed flow restriction will not give you the response to demand that you want. The OAT reset supply water temp will give you the lower return water temp that you want, reduced on/off cycling of the load, and allow the Windhager to turndown the firing rate to match demand with a longer on cycle at a modulated firing rate.
You want to vary supply water temp with demand and have sufficient flow the have a reasonable delta T across the loop. Very little flow may be fine but the pump flow rate has to vary as additional zones cycle on and off or come up from a cold start.
Two loop zones, one per floor, each driven by a Taco 007. The oil fired system works fine, maybe a tad noisy near the first baseboard' incoming elbow, but it heats the place fine. I'm going to have to add a pump for each boiler to pump toward the buffer tank in a parallel manner. What you're suggesting is probably too fancy for me to attempt so I'll probably go with minimal practical changes. You make a good point: 'you want enough flow so delta T is not huge at the end of the loop, overheating the early convectors and underheating the end loop convectors.' I'm assuming the boiler pumps will be fixed, but adjustable speed, so I have to dial that flow in somehow so that everything is fine with both zones running at the same time. What I'm inferring from what you're saying, taking away the fancy injection stuff etc, is that a delta T pump on each zone might be worthwhile. I still drawn to dialing in an adjustable speed pump to desired flow for my application where pressures are consistent. This is just a 120 gallon buffer tank after all, not 1000 gal storage.
Edit: There's really a bunch of stuff I don't fully grasp. Sorry for all the questions.
Edit: There's really a bunch of stuff I don't fully grasp. Sorry for all the questions.
Last edited:
Keep asking questions. It's a lot cheaper than building something and then learning what you should have or could have done after the fact. I would never expect the homeowner to understand what I do, or most contractors.
Primary secondary pumping with OAT reset of the secondary loop is a relatively industry standard method. It's rare and a cost adder, so I would never expect to see it in any house just because of the extra cost. The customer is not expected to understand it but they do understand it costs more and that's why it's not done commonly. It would make me uncompetitive to bid that against a conventional install typical to what you already have.
I'm sure one of the TarmUSA drawings must show this.
I would hesitate to give specific advice above my qualification, and I have not read all of your thread, but are you planning to take the oil out and go 100% on the Windhager? Usually the smartest way to do it is to get the dealer and factory support. They should be able to supply you with the recommended piping diagram and control strategy for your application. Self install ?
Hot water baseboard is probably the most common load for a residential boiler. Windhager should have a standard reference install showing how to tie the boiler into what you already have or would want to upgrade to. The OAT reset of the load water supply temp would seem to be a match for the Windhager's ability to modulate the firing rate, and that's where a gain in efficiency and easier operation will be. Get the factory support for your install.
Primary secondary pumping with OAT reset of the secondary loop is a relatively industry standard method. It's rare and a cost adder, so I would never expect to see it in any house just because of the extra cost. The customer is not expected to understand it but they do understand it costs more and that's why it's not done commonly. It would make me uncompetitive to bid that against a conventional install typical to what you already have.
I'm sure one of the TarmUSA drawings must show this.
I would hesitate to give specific advice above my qualification, and I have not read all of your thread, but are you planning to take the oil out and go 100% on the Windhager? Usually the smartest way to do it is to get the dealer and factory support. They should be able to supply you with the recommended piping diagram and control strategy for your application. Self install ?
Hot water baseboard is probably the most common load for a residential boiler. Windhager should have a standard reference install showing how to tie the boiler into what you already have or would want to upgrade to. The OAT reset of the load water supply temp would seem to be a match for the Windhager's ability to modulate the firing rate, and that's where a gain in efficiency and easier operation will be. Get the factory support for your install.
Will not take out oil. Will follow dealer recommendations, but impatient and find this stuff interesting, dare I say, fun-need to buy some books and actually read them. Yes, self install.
So, the current operations plan, derived from looking at a combo of Tarm and Windhager schematics, and without reset, is to supply the buffer tank at the top with 175F water, which I understand is the max setpoint for the BioWin. The boiler, pellet or oil, will turn off as a lower aquastat reaches 175F, I imagine. If there is a call for heat while the tank is circulating, and the zone circs start up, Ts in the supply and return header will divert flow directly to the zones. I figure the tank might get as low as 135F or so, because it serves double duty to generate heated domestic water through a coil in the tank, and 135 might be getting on the low side for STANDARD baseboard, which I currently have. The circulator pumps will turn on and off to satisfy the thermostats.
If OAT reset of the load supply temperature is used, if the the buffer tank is charged, the mixed lower temp of the load supply, in milder weather, will allow the circulators to run longer (consuming more electrical energy) at a lower temperature rather than cycling on and off at a higher temperature. I'm not so sure what will happen if the buffer is depleted. The boiler's 175F water will be mixed down (I understand these mixing valves can also provide boiler protection) to a lower supply temp, while the buffer tank is getting recharged at the same time. The circulators will run longer at a lower temperature, even below what the normal non-condensing boiler could take. The buffer tank would be charged sooner because there are more BTUs/hr availabe. I'm at all sure how or if the modulation comes into play.
I've read that OAT reset saves money, and I've even fitted a Tekmar unit on my oil boiler, but I'm still not totally convinced of the need here, since I don't think I should be messing with reset on the new boiler if it's not built in, and with using a buffer tank.
So, the current operations plan, derived from looking at a combo of Tarm and Windhager schematics, and without reset, is to supply the buffer tank at the top with 175F water, which I understand is the max setpoint for the BioWin. The boiler, pellet or oil, will turn off as a lower aquastat reaches 175F, I imagine. If there is a call for heat while the tank is circulating, and the zone circs start up, Ts in the supply and return header will divert flow directly to the zones. I figure the tank might get as low as 135F or so, because it serves double duty to generate heated domestic water through a coil in the tank, and 135 might be getting on the low side for STANDARD baseboard, which I currently have. The circulator pumps will turn on and off to satisfy the thermostats.
If OAT reset of the load supply temperature is used, if the the buffer tank is charged, the mixed lower temp of the load supply, in milder weather, will allow the circulators to run longer (consuming more electrical energy) at a lower temperature rather than cycling on and off at a higher temperature. I'm not so sure what will happen if the buffer is depleted. The boiler's 175F water will be mixed down (I understand these mixing valves can also provide boiler protection) to a lower supply temp, while the buffer tank is getting recharged at the same time. The circulators will run longer at a lower temperature, even below what the normal non-condensing boiler could take. The buffer tank would be charged sooner because there are more BTUs/hr availabe. I'm at all sure how or if the modulation comes into play.
I've read that OAT reset saves money, and I've even fitted a Tekmar unit on my oil boiler, but I'm still not totally convinced of the need here, since I don't think I should be messing with reset on the new boiler if it's not built in, and with using a buffer tank.
The OAT reset does not connect to or control the boiler supply water temp. The reset you have on your oil boiler would have to have a low limit above 140 deg F to prevent flue gas condensation. I would not consider or think of using reset that way. The Biowin also would be maintained above the condensing temp and if not rated for low return water temp, the primary boiler loop is not reset, the secondary load loop is.
Without reset, the buffer tank will never be going below the boiler aquastat on temp as long as fuel is available. If the Boiwin supply temp setpoint is 175F with a ten degree differential, it may turn on at 170F and off at 180F. When it turns on and is below setpoint, it will fire at 100% to come up and start to modulate at the maintenance temp. This is the general control scenario. Above the setpoint, if the supply water temp continues up because of no load, the boiler goes off.
At 175F, if you have a steady small load that matches boiler output (not the buffer tank) the boiler may modulate, turndown, and match output to the load. This has a better chance of happening if the loads are reset and on at a lower reset water temp than if the loads are getting straight 175F boiler temp water and doing on off cycling.
I would absolutely forget about the electricity cost of the circ running longer as it is such a small number. However, if you can reduce start stop cycles of the Biowin by half monthly, by operating the boiler in its modulating range, it should be burning cleaner with less maintenance required and better overall satisfaction.
Typical reset controls have boiler return water protection where they will not supply the load for return water temp below the protective setpoint and ramp up demand as the boiler return water comes up. With the buffer tank and fuel available, I would think the buffer will always be hot and return water always available.
In the scenario you are talking about, there would be no stratification of the buffer tank when on because the boiler is always available to heat it. It is basically a dump load for the boiler off cycle, but would not be used much for ride through. The boiler would restart for on demand heat call. This is where reset of the loads would come in, the loads would stay on longer at the reset temp and not go on/off, allowing the Biowin to try to modulate down to meet demand at the boiler setpoint.
Resetting the load loops, you could have reset temp all the way down to 90 deg if if that will satisfy demand on mild days and probably 140 F max on peak demand days, while the boiler loop is steady at 175F. Reset sees the biggest gains on the mild days, and gives more even heating since it is eliminating the differential between heat on and off calls.
Boiwin should have a reference design showing reset of the loads, not reset of the boiler.
Without reset, the buffer tank will never be going below the boiler aquastat on temp as long as fuel is available. If the Boiwin supply temp setpoint is 175F with a ten degree differential, it may turn on at 170F and off at 180F. When it turns on and is below setpoint, it will fire at 100% to come up and start to modulate at the maintenance temp. This is the general control scenario. Above the setpoint, if the supply water temp continues up because of no load, the boiler goes off.
At 175F, if you have a steady small load that matches boiler output (not the buffer tank) the boiler may modulate, turndown, and match output to the load. This has a better chance of happening if the loads are reset and on at a lower reset water temp than if the loads are getting straight 175F boiler temp water and doing on off cycling.
I would absolutely forget about the electricity cost of the circ running longer as it is such a small number. However, if you can reduce start stop cycles of the Biowin by half monthly, by operating the boiler in its modulating range, it should be burning cleaner with less maintenance required and better overall satisfaction.
Typical reset controls have boiler return water protection where they will not supply the load for return water temp below the protective setpoint and ramp up demand as the boiler return water comes up. With the buffer tank and fuel available, I would think the buffer will always be hot and return water always available.
In the scenario you are talking about, there would be no stratification of the buffer tank when on because the boiler is always available to heat it. It is basically a dump load for the boiler off cycle, but would not be used much for ride through. The boiler would restart for on demand heat call. This is where reset of the loads would come in, the loads would stay on longer at the reset temp and not go on/off, allowing the Biowin to try to modulate down to meet demand at the boiler setpoint.
Resetting the load loops, you could have reset temp all the way down to 90 deg if if that will satisfy demand on mild days and probably 140 F max on peak demand days, while the boiler loop is steady at 175F. Reset sees the biggest gains on the mild days, and gives more even heating since it is eliminating the differential between heat on and off calls.
Boiwin should have a reference design showing reset of the loads, not reset of the boiler.
Last edited:
Just wanted to add, the VS reset injection pump is not a fancy item. The Tekmar VS injection pump controllers in my photo are made to work with standard wet rotor circs like the Taco 007. Taco makes a special model of circ with onboard reset controls, but I would prefer separate circ and controller for servicing issues. it will be asier to changes one part or the other depending on what part failed instead of one expensive Taco circ with the self contained reset control.
In the future the VS circs will be ECM , as ECM is ideal for VS, but they are not on the market yet AFAIK.
I think if it were me I would be looking to install the Biowin with no oil and no buffer tank, but absolutely with a secondary reset loop for the baseboards. That is if the Biowin is rated for install without a buffer tank. There will be a way to scavenge heat from the boiler to the load in the boiler off cycle using the controls, but it is a custom scenario.
In the future the VS circs will be ECM , as ECM is ideal for VS, but they are not on the market yet AFAIK.
I think if it were me I would be looking to install the Biowin with no oil and no buffer tank, but absolutely with a secondary reset loop for the baseboards. That is if the Biowin is rated for install without a buffer tank. There will be a way to scavenge heat from the boiler to the load in the boiler off cycle using the controls, but it is a custom scenario.
- Status
Similar threads
- Locked
