Pb 105 installed...up and running
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Changed all my set back thermostats (up from 50 degrees) and now my wife is very happy(house @ 70+ degrees) My oil still come on at times but in 24 hours it has only run 30 min (hour meter). would like to nip that in the butt. My boiler is plumbed in series and no one here seems to know how to stop my oil burner from comming on . I only want my oil to come on in an emergency. Can anyone help?
THE ANSWER
Your boiler has a built-in control circuit that identifies the pressure in your boiler. If there's a lack of pressure, the unit has been set for generic, easy-to-use operation.
You need someone who knows how to wire control circuits and is familiarized with electricity to revamp your system.
Inspect your wiring. Hopefully the unit has a wiring diagram in the instruction manual, online, or through their technical support/engineering department. I bet you'll find that there's a little circuit that goes from normally open contacts to closed when a pressure meter shows a pressure at or below 110 psi, or whatever the psi settings are for the boiler.
That meter is in your boiler. Locate the device that recognizes your pressure in the boiler/system. Now the boiler might have multiple devices to monitor pressure, independently triggering an event based on JUST low pressure, and another one triggering an event based on JUST high temperature. Or (correct me if I'm wrong) it recognizes what the pressure is, then that signal gets sent to the control box, where the events are triggered in the control box.
If there are independent pressure sensors dedicated to high and low pressure, then find which one just does low pressure. Stopping that circuit will solve your problem. I'd suggest finding a way to stop the circuit where you can put it back together, though. So don't do permanent, irreversible damage to your system.
If the unit recognizes both high and low pressure, and just sends the PSI reading to the control box, what I would then suggest is to set up a relay to a secondary thermostat with the lowest degree setting you can find. This would most likely be an electronic thermostat, which is awesome. I think there are wireless ones, where you get a box with the thermostat that will connect into your boiler. This will, in essence, be the switch that will ALLOW your normal boiler circuitry to trigger. What it's going to trigger is a relay, which will have a couple of wires going to the thermostat, and will INTERRUPT the normal hot lead going into the system. You should be able to interrupt the circuit AFTER your emergency shut off switch.
You can also set up your control circuit to have a safeguard against turning off the system completely when the blower is on and the unit is hot, i.e. the firing process. Run a DoDE (or delay on de-energize) timer on the circuit, and have the timer, when activated, disconnect your primary thermostat's circuit. Make sure to time how long it takes for your boiler to re-pressurize (using a worst-case scenario of starting from 0. This requires turning your system off until there is no pressure, turning the system off, and timing how long it takes to go through the process of getting up to pressure.)
Put it all in pretty boxes, get yourself a voltage transformer, run some romex or MC to it from the last junction box before your boiler, and before the controls I'm talking about. And before your emergency shut off switch. Then your control system will be powered regardless of power state of the boiler, with the exception of the breaker or main breaker tripping in your panel. Again, you want a dedicated breaker for this system, anyways...don't want any hair dryers shutting off your pellet unit when it's mid-fire.
Or you can run a switch to the top of your stairs and turn the unit on and off. Just don't turn it off when it's in the middle of combustion.
I know it's a really long post, and I apologize.