Flow meters

[nymapleguy607]

Okay guys, This year I have the new evaporator and I really want to see how much I am boiling off per hour. I want to install a flow meter between the feed tank and the preheater but I don't want to put something in there that might block my sap flow to the evaporator. I found a meter from Mcmaster That has a vertical tube and a stainless steekl float inside I think I can hook this type up with a tee and use it that way
Anyone got a suggestion
Thanks
Jeff

[brookledge]

With a small evaporator the flow isn't as much as larger ones so you could put one in line from the head tank to the evaporator. The concern I have is that it might be to restictive since it is only gravity fed and if you need alot of sap fast is it going to allow that.
The other thing that you need to look at is what the specs are on the meter, especially the minimum flow. Many times the float will only allow a trickle through while other times it is flowing good. Well some meters will not detect or record trickle or dripping flows but yet they add up.
The meter I use is the type that is used for a house service from a city water dept. It is ment to flow under pressure. I had it in line from my pump that fed the head tank. That way my 1 1/2" line to the evaporator is not resticted.
Keith

[michelle32]

I agree. If you want a accurate reading you need to get it when you pump into your feed tank. To many things can go wrong on the out put side of your head tank. Why take the chance. Keith

[3rdgen.maple]

This has been discussed about a million times already and if I recall they are inaccurate. Maybe Dr. Perkins can chime in here as well cause I remember a thread on this where Proctor does not use them because of their inaccuracy. I know guys say they are but exacally how do they know this? Personally I put in a clear tube after the valve on my holding tank and after measuring the tank and doing some math I mark of 10 gallon increments on the sight tube. I can get an overall daily gph or an hourly one just by checking the tube. It also allows me to seee how much sap is left in the tank with a quick glance. I did put a little red ball in the tube so it is very easy to see. If you are unsure of the math fill your tank with specific amounts of water and mark it as you go. Or heck a good old yardstick dipped in the tank will get you the same results.

[howden86]

I checked how much my tank would hold by measuring it with a tape ruler for area then timed how much sap I went through in a given time of minutes. The dealer didn't believe me so he put a flowmeter on it and it verified my accuracy. I was within 1/2 of sap per hour to their flowmeter.

[KenWP]

I measured how much sap was pouring in to the pan for 60 seconds and then did the math. Never seemed to be able to get much over 3 british gallons a hour.

[RileySugarbush]

We use one of the rotometers from McMaster Carr as a guide to how we are feeding. As noted, they are not perfectly accurate but they do a pretty good job of keeping you informed during a boil. 60ghp max range. When compared to our measured sap pumped to the head tank, I think it is pretty accurate.

You have to have clean sap or a filter mesh up stream because the small passages will clog up with debris easily. Have a quick way of bypassing and taking the meter out without a big interruption in your feed. A surprise was that when you lose a boil the feed flow increases dramatically to make up for the level drop in when the bubbles are absent. When we fire, the blower are turned off and the flow temporarily jumps to peg the meter at 60 GPH. After the doors are closed and the blowers are on the flow drops way down for a while when the level jumps up again.

You have to get used to these characteristics before they are useful, but I really like to see a steady 50gph flowing in for long periods!

[WESTVIRGINIAMAPLER]

I have a water meter between my 625 gallon sunset milk tank and my 320 Lappierre feed tank. It is very accurate because I record total gallons boiled for day and divide it by boiling time including startup and shutdown to get an accurate reading of exactly how many gph for day. You could put a line on the liquid level gauge for the feed tank and pump up to that line at the same time every hour and it would give you exactly how many gph you boiled. You might have to start pumping 2 to 3 minutes before to hit exactly on the right time, but you could play with it and get it right. I don't think a flow meter between feed tank and evaporator is the best idea, I have seen guys on here run evaporators dry because of one.

[maplwrks]

Up here in Vt., we don't use flow meters-- It's simpler to measure the amount of syrup made in an hour, and work your #s backwards. If you make 2 gallons of syrup an hour, your rig runs about 80 gph. There is no need to complicate things with equipment that may not be accurate in your application anyway!

[WESTVIRGINIAMAPLER]

Mike,

Sounds good, but every year is different. Talking to Jim Desjardin(mapleman3) yesterday and he was 40 to 1 in 2008 and about 60 to 1 in 2009 in Mass.

[RileySugarbush]

Brandon, I agree our inline flow meter is a hazard. If it clogs we are in trouble, so this year I will put a bypass valve on it. Our is not a totaling meter but instead give instantaneous flow rate. It doesn't help make better syrup, and probably not even more syrup, but it's fun to watch!

With four of use working the rig, plus all the temporary helpers, it is tough to keep track of total volume in to the evaporator. We really only get a rough measure. As Maplwrks says, we keep an accurate measure of syrup produced and sugar content in the sap to double check our rate.

[maple flats]

I have a meter on the line that feeds my elevated tank, sometimes it works and often times not. If you go with one for the fun of it you might still want to work backwards, do the math and test your sap sugar % in. %'s change thru the season and even thru the day and can vary widely from season to season.

[PerryW]

Every additional valve, meter or fitting you install in your sap feed line is just an additional place to freeze up, clog, leak or fail.

[KenWP]

I would say that in the long run how much syrup you get is the goal. At what rate you boil or how long you boil is going to be pretty much the same just the sugar content will be different. I see all kinds of figures stated and I have to wonder about them some times.
I worked with guys who figured that numbers were better then hard work to produce more and when they didn't get the numbers they wanted with out doing more work got upset over it.

[lew]

I have used a flow meter for years on our 5x10 all flue rig. I am oil fired, so the input of sap is steady. I also have an RO, so the sugar content is also steady. The evaporator is large so the flow is large. I also use a high/low level warning system to let me know the depth of the sap in the pan. The probes for the level alarm are in a glass sight tube on the side of the pan so that the level can be visually monitored as well. I run it at 3/4 inch above the flues. Our rig runs at 3.5 gpm when boiling conditions are right. Different pressure systems make evaporating harder to accomplish, and this is noted in the flow meter. Sometimes we are down to 3.0 gpm. I used to leave the float on years ago, but now have installed a gate valve between the feed tank and the meter. I should note that i have a small feed tank, about 20 gallons, with a float switch from it to the main feed tank. This small feed tank has a relatively constant level in it, it only fluctuates about 2 inches. This keeps a constant pressure on the meter and keeps it more accurate. I do have a bypass line in case of emergencies. I have yet to use it. With the hi/lo level alarm and constant/vigilant visual tracking I am able to comfortably boil a lot of sap. Not as fast as some, but fast enough. I always had problems with floats, either way to much or not enough. With this system I can dial it in for the day and boil away. Love it to death. BUT, with any system you use to control the level of sap in your pan, you should NEVER count on it it fully. Only trust your eyes. Check it visually all the time. I have a sight tube marked with a magic marker and a rubber band so that I can see the level from a considerable distance. I still don't even trust this. Several times a day I will pull the level probes from the sight tube and blow back through the sight tube to make sure it hasn't become plugged and to make sure that the low level buzzer is still working. I also open the steam hood opening several times a day to check levels this way. Sorry to be so long winded, but I for one love the flow meter. I have just adjusted my practices to a comfortably safe level to tolerate them. NO system is perfect. Only constant monitoring will save your hide and your pan.