Aquastat Pellet Boiller What Setting

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My minimum is set to 160, maximum 200 ~ but mine does not operate the same as yours. My maximum is the safety shut off point, and 160 is when it will shut off pellet consumption. IF/WHEN it gets really cold I will bump up the 160, then lower it if it isn't going to be as frigid for a period of time.

On your boiler I would set it like you had your oil boiler ~ probably low 140 high 170?
 
This is the model aquastat i have http://www.supplyhouse.com/Honeywel...stat-100-240F-range-5F-Differential-1704000-p It is set at 100 right now What exactly does this do?


I said it before and I'll say it again. You get what you pay for. When you were looking at purchasing a boiler, I tried to steer you away from the Harmon because of the "what ifs". You have had constant "what ifs". Had you bought a Pinnacle there would be someone to take care of the "what ifs". They were comparable money..........

I have no idea how your system is set up, but on mine that circulator aquastat is what controls when my oil boiler kicks on if for some reason my pellet boiler couldn't keep up with the demand, or malfunctioned. Mine is set at 140.
 
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This is the model aquastat i have http://www.supplyhouse.com/Honeywel...stat-100-240F-range-5F-Differential-1704000-p It is set at 100 right now What exactly does this do?
It depends on where that aqustat is located, I have mine located in the oil boiler to control the circulator running between the OB and PB. You need to determine what that aqustat is controlling, the PB controller, high-low settings should be controlling the temp in the PB, I have mine set, Low 160*, High 180*, meaning when the boiler water temp drops to 160* the boiler will start up, when the water temp reaches 180* the boiler will shut down. When we actually get into the heating season, I switch my boiler into manual mode but you need a dump loop to run in manual in case of a overheat situation.
 
mine is located in the top of the Pellet boiler, the oil boiler has its own but its different than the one i have on the PB

I thought thats what the low control on the pellet boiler was to control that it turns on if it gets below the set temp on the Minimum dial
 
Do you have the,(as Harman calls it), the aqua temp sensor,part # 3-20-72180 installed in the top of the PB? This sensor connects to the boiler control board which starts the boiler at the low setting and shuts the boiler down when it reaches the high setting. A picture of the top of the pellet boiler showing the location of the aqustat that you posted a link to would be nice, no idea why this aqustat was installed.
 
Here are some pics
 

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It appears, looking at the photo of the Honeywell aqustat and circulator, that this aqustat controls just the running of that circulator. I'm gussing that this circulator, circulates water between both boilers. Now, if this is true, with a setting of 100* on the aqustat, the circulator will run and never shut off until the water temp in the boiler is below 100*. IMHO, if the intent was to keep equal temps in both the OB and PB, turn the circulator off when they equal the setting, the aqustat should have been installed in the OB, plus the fact it's not the correct aqustat to do this.
 
Mine is not connected like yours. My PB105 is in parallel with my oil boiler and the circulator on the PB105 is connected to the oil boiler aquastat. I also have a shutoff switch and ball valves to isolate the PB105 if I need to. My PB105 only uses the sensor in the dry well on its top to determine when to start and stop. The oil boiler still controls the flow of hot water. My pellet boiler has no aquastat of its own. I don't know if that's the most efficient way to do it, but that's how my installer put it in.
I have had trouble with that water temperature sensor on the pellet boiler since it was new. If I put it all the way to the bottom of the dry well, it shuts off too soon and doesn't get the water as hot as it should. I had to experiment with different depths for the sensor until it would shut off at the high water temp setpoint.
 
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Mine is not connected like yours. My PB105 is in parallel with my oil boiler and the circulator on the PB105 is connected to the oil boiler aquastat. I also have a shutoff switch and ball valves to isolate the PB105 if I need to. My PB105 only uses the sensor in the dry well on its top to determine when to start and stop. The oil boiler still controls the flow of hot water. My pellet boiler has no aquastat of its own. I don't know if that's the most efficient way to do it, but that's how my installer put it in.
I have had trouble with that water temperature sensor on the pellet boiler since it was new. If I put it all the way to the bottom of the dry well, it shuts off too soon and doesn't get the water as hot as it should. I had to experiment with different depths for the sensor until it would shut off at the high water temp setpoint.

HE said mine was supposed to be parallel so if ran out of pellets oil boiler would turn on. Also he talked to the dealer to discuss the install before doing it
 
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should i turn that temp up on the aquastat? will it make any difference? The pipe from the return water on the pb connects to that circulator. The min on oil boiler is 140 i believe
 
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If you adjust that aqustat to say 140*, the contacts of the aqustat will not close to run the circulator until the temp at its location gets to 140*. If the installers intent is for that circulator to equal the temps in both boilers, shut down when this happens, it's not going to shut the circulator down because that aqustat contacts close on temp rise, you need a aqustat that opens on temp rise in order to shut down the circulator,again, if this was the installers intent to shut down the circulator.
 
You should leave it at a setting of 100*, to make sure that the circulator does run to equal the temps in both boilers. Actually, the aquastat that the installer installed is doing nothing for you, the aquastat wasn't needed to have the circulator run all the time, no matter what the temps in both boilers are. This link is to the correct aquastat that should have been installed.

http://www.supplyhouse.com/Honeywel...0-240F-range-5-30F-Adj-Differential-1703000-p
 
i know at one time i was having an issue of it burning alot of pellets huge amount. HE came down and turned the aquastat to 100 and turned the circulator speed down a couple notches

Just trying to see if i can save a few more pellets some how lol

Not sure why he would install the wrong thing, he is one of the best plumbing and heating guys around very knowledgeable, this was his first pelelt boiller though and thats why he discussed it all with the dealer before doing anything. Said its hooked up just like the oil boiler

How many bags are you burning a day?
 
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It all depends on the temp outside on a given day. Last year I burned 8.5 tons, running the boiler for heat and DHW for the entire year,(365 days) heating 2200 sq. ft. If you're okay with the circulator running all the time, using power, creating heat loss through the piping between the boilers using more pellet fuel to keep both boilers equal in temp, so be it,.........but if I were you, I would call the installer, asking him what the purpose of that aquastat is other than keeping the circulator running all the time, just to get his response.
 
wat exactly does the taco 1 zone switch relay do on the PB theres wire that runs to the argo on the oil boiler wire also runs to the low water cutoff box ten wire runs from that to the aquastat and the wire runs from that to the circulator on the water return

I just went down and circulator is off, pelelt boiller is not running, i turned the aqua stat from 120 to 100 and the circulator kicked on

Ive used 3 bags since Saturday 4pm for some heat and hot water. We are a family of 5 with a dishwasher so we do use quite a bit of hot water
 
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Sorry, I can't help you, I don't have a wiring diagram for the way the installer wired it. I do know that Honeywell aquastat has NC contacts only so when its set at 100*,if the water is above 100* then this set of contacts close to energize a circulator or whatever. Like I've already mentioned, your best bet is to contact the installer and ask him what the aquastat function is and any other device that is installed to circulate the water between the pellet boiler and oil boiler.
 
It increases or decreases the flow of water between both boilers. I have a 007 Taco circulator on mine (single speed) to circulate between the boilers. If your circulator was set to its slowest speed, it would slow down the flow of water to the oil boiler,I don't see the advantage in doing this because, IMHO, the quicker that water from the oil boiler is pumped to the pellet boiler to be heated, the sooner MY aquastat will shut this circulator off.
 
All I know is my PB105 has no aquastat at all on it. When the oil boiler needs heat (for hot water or heat), its aquastat turns on the PB105 circulator. The down side is, the oil boiler is not an automatic backup. I have to leave it switched off and turn it on manually when I want to use it. But, the PB105 is not circulating its hot water when it's not needed.
 
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