Device to measure run time on my boiler – i.e. hours meter?
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Is there an inexpensive device I can attach to my forced hot water oil boiler — I’m thinking of an hours meter that you see on boat engines — that will track how long my boiler runs?
I’m thinking of replacing the boiler with a heat pump hot water tank, but before I do that, I’d like to know exactly how much oil this method uses to heat my domestic hot water.
I know there are systems you can install at the panel with clamp meters for every circuit to track electrical usage, but I’m hoping for something for a single circuit/device.
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Well, I think you will want to have it installed on the wiring to the gun, if you did it on the breaker it would run when the circulator is running in addition to the gun.
There are many options for this. You just need to wire the hour meter so that it's running whenever fuel is being supplied to the boiler, so find an easy place to tie into the boiler controles that is always energized when fuel is being supplied. A simple 24v hour meter that's pretty inexpensive (about $30) is available here:
https://www.grainger.com/product/ENM-Hour-Meter-24V-AC-2PAY7
You can get these made to operate on 120v power or 24v AC control like common HVAC control systems use. they don't draw much power, so should be able to be easily tapped off of just about any circuit in the system without trouble.
Bill
I used one of these:
Onset HOBO UX90-004 Motor Usage On/Off Data Logger
It senses the electric field from an AC motor (the forced draft motor) so you don’t need any wiring. It is magnetic so just attach it to the housing close to the motor. Software was also pretty intuitive to use