digital flow meters (water and gas)?

hydro_newbie

Can anyone recommend flow meters that I could use to measure the volume of water that passes through a hot-water boiler vs time? Also, one to measure the volume of gas consumed? I'm interested in the possibility of quantifying boiler efficiency vs time as it starts up and reaches steady state (so metering would need to be on intervals of tens of seconds I think).

Ideally the meter would be digital, and there would be some way to access the data electronically (this seems like it might be a tough requirement). Some looking online hasn't turned up much, so I thought I'd see if anyone here can come up with something.

I've seen mention of 10 minutes minimum 'on time' for a boiler to avoid significant losses due to start up, but nothing really quantitative anywhere.

ratio

eBay has a few different models of ultrasonic flow meters from China, for instance this one. I've been thinking about trying one, but haven't gotten up the courage to pull the trigger yet. Bear in mind that you may have to purchase the high-temp transducers separately from the meter, I don't recall seeing one that came with them.

hot_rod

BTU meters are fairly common and easy to buy. They measure flow rate and temperature differential to give you an energy calculation. You can read just flow rate also. It is a simple basic water meter, rated for high temperature use.

Many buildings in Europe that are connected to district systems get billed via BTU meters. Soon we will have a BTU metering standard here in the US, it's been in the works for several years.

Once a standard is established, equipment can be built to that standard to meter energy with approved devices.

Gas meters are fairly common also, most homes and buildings have them and you can buy them also. Most recent styles have the ability to be read remotely, or online.

I'm familiar with this brand of BTU meters, they also have gas meter and loggers.

http://www.onicon.com/Btu_meters.html