Triple Aquastats, Could You Explain the Diffrential to Me?

I have always wondered what the diffrential did, right now on my oil boiler I have the hi at 180 and the low at 160 with a 15 deg diff, could you explain what it does and also how would I want to set them when I hook up my k6 which also has a triple I believe.

And what is the diffrence between a triple and a regular when I ordered my boiler I paid more to get the triple, I have abuilt in coil in my oil boiler but I only use my indirect and I probably will not use the coil in the k6 either.

Here's a thread that explained aquastat functions fairly well.
Stoker Boiler Operating and Temperature Controls

OK I read that and it make a little more sense, I am going to be setting my k6 to 180 hi 160 lo and what should the diff be? the auqa stat on my boiler will go to 140 hi 120 lo and what should the diff be? I have a indirect hot water heater hooked uop as a zone the coils are not used. Currently my oil boiler is at 180 hi 160 lo and a 15 deg diff. It seemed that the diff was for domestic HW coil.

The circulator between the boilers is goingto run constant.

Figure 22 on page 13 describes exactly how it works.

http://www.exqheat.com/images/aquastatL8124_honeyw.pdf

So how do I want mine set The oil boiler and coal boiler they will be hooked up parreal. thanks

Hi, I was just wondering if I could get a answer to this ?
Thanks

OK I read that and it make a little more sense, I am going to be setting my k6 to 180 hi 160 lo and what should the diff be? the auqa stat on my boiler will go to 140 hi 120 lo and what should the diff be? I have a indirect hot water heater hooked uop as a zone the coils are not used. Currently my oil boiler is at 180 hi 160 lo and a 15 deg diff. It seemed that the diff was for domestic HW coil.

The circulator between the boilers is goingto run constant.

What should it be? I am unsure if I am going to hook up in series or parellal. Thanks

The differential sets the point below the maximum setting (say 180*) that the boiler will fire on a call for heat. If it were set at 10* and your boiler has run up to it's maximum setpoint and shut down, the boiler will fire only during a call for heat (in this case 170* and below) and stop firing once the call stopped. It would continue this procedure until it gets to the low limit, at which point it would fire again until it reaches the high and start the process over. If you have a boiler that has plenty of punch for the load, you can crank it way up to say 20-25*and not use it. If the boiler runs low on heat quickly, tighten it up to 10* and it will fire sooner rather than later.

I set mine at 15* for $0.02, generally that is the standard for a solid fuel boiler IIRC. It makes no difference how the boilers are plumbed, it just gives the boiler a head start on demands placed on it.

And the low limit setting is when your circulators will shut off so as to not draw the boiler temp down to much.
DON

Coldsweat that applies to a triple auqastat also? The diff does not affect the low limit though just the hi? thanks

Yes. It doesn't effect the high or low limits. It calls for more heat when the boiler temps are in a downward trend (after reaching the high limit and shutting down). Because the temps are heading down, the differential will fire the burner when a heat call is sent, this keeps the boiler from cycling repeatedly top to bottom. Think about driving a loaded truck along the highway at 60 MPH. It doesn't take a lot of throttle pedal once your moving. But when you get to a hill (heat call), you give it some more pedal or you will be going pretty slow when you get to the top.

https://customer.honeywell.com/techlit/pdf/Packed ... 0-2553.pdf

"At any differential setting greater than 10°F (6°C), the
R-B make and R-W break temperatures remain the same
(control setting minus 10°F (6°C). The R-B break and R-W
make temperatures are the setpoint temperatures plus the
difference between the differential setting and 10°F (6°C).
EXAMPLE: Setpoint of 140°F (60°C) differential set at
25°F (14°C). On a temperature rise, R-B breaks and
R-W makes at 155°F (68°C). On a temperature fall,
R-B makes and R-W breaks at 130°F (54°C); see
Fig. 7."

Look at figure no. 7, it shows the relationship and how the switches make and break. Some on a temperature rise, some on a fall.