AHS S130 Immersion Wells question

How many "spare" (unused) immersion well locations does a standard S130 Coal Gun have available?

Gosh, I'm not 100% positive, but I don't think they have any spares. Why are you hoping for a spare? Might a strap on aquastat work for you?

I was planning on adding an aquastat that would allow my primary circulator to run only when the boilers temperature is at or above 140 degrees (so if the boiler goes this low the circulator does not run and further drag down the boilers temp until it goes below the flu gas condensing point where corrosion will start happening). I figured that for this specific application the best place for the aquastats temperature bulb would be right in the boiler chamber, rather than placing it just above the boiler on the supply pipe.

Why don't you just run the primary circulator off the triple aquastat? That way the circulator will not be able to run below the low limit setpoint. e.g. 160 degrees. I have installed two boilers in the last three months with this configuration, they run excellent.

-Rob

They are rated for steam, so there would be at least 2 ports open.

markviii wrote:Why don't you just run the primary circulator off the triple aquastat? That way the circulator will not be able to run below the low limit setpoint. e.g. 160 degrees. I have installed two boilers in the last three months with this configuration, they run excellent.

-Rob

I have a copy of the AHS Coal Gun Installation and Operator's Manual manual now, and the AHS S130 Coal Gun comes with a dual aquastat, not a triple. The wiring diagram shows that the dual aquastat on the AHS is a Honeywell L4081B. It shows one leg of this aquastat (the low temp leg I presume) going to the blower motor, and the other leg (the high temperature leg I presume) available for optional use as a high temperature level dump zone circulator initiator. I don't have a dedicated circulator on my dump zone, but rather I have only a 24 V normally closed zone valve.

Previously I had assumed that the Honeywell L4081B was an open on high temperature rise aquastat in conjunction with a close on low temperature aquastat (I.E., two separate aquastats, thus dual), so I wonder how having it open when the boiler reaches its dump temperature would start the dump zone circulator. It seems as if it should be shutting down the circulator instead, but I know this can't be right. Perhaps the blower is attached to the 'nominally' high level leg, and the dump zone circulator would be attached to the 'nominally' low temperature leg. ??? Obviously I have a lot of learning to do. Good thing that it comes fully assembled sans for the need to attach the feed hopper.

Don't make any assumptions on the number and location of the tappings on current production AHS coal gun boilers. Way back when it was Eshland there was a published chart that specified possible locations and sizes for tappings. You ordered what you wanted. Today I don't know. I do know at least one forum member who did not order a factory installed domestic coil was very disappointed when his S130 arrived without the 4" tapping for adding a domestic coil later. Get what you are expecting in writing including an engineering drawing showing sizes and locations. The current AHS coal gun brochure posted on their Web site is lacking these important details. It also show photos of the old round (not square) hopper and no height dimension above the floor. You are forewarned.

Since this thread is starting to duplicate my other thread titled , I'm following up on the older thread for all of the aquastat function stuff, and hoping that this thread will stay focused only upon the topic of answering how many immersion well spots does an AHS have open and available.

I've posted a drawing on the "AHS S130 Coal Gun : Aquastat question?" thread that I would like critiqued.

This must be their new website address: http://alternateheatingsystems.com/CoalBurners.aspx

I see only the new style hopper models represented.

I have the Thermo Ash Monitoring Control, the DHW Coil, and the belt drive all in writing on my receipt.

I take it back, the web site only shows the current square hopper photos. I do have a coal gun pdf specification document that was recently sent to me that only shows the round hopper style. It appears the pdf specification document is not linked on the web site.

I was forwarded a copy of the install and user manual, and you are right, it still shows the round hopper model(s).

I spoke with Alternate Heating systems today, and the S130 Coal Gun does have one available tapping that can be used for an add-on Aquastat.

Isayre:

I don't know the Honeywell numbers off the top of my head, but my S130, delivered in mid-2008, has 2 control "boxes". On the front of the unit is the primary fan control. This oblong control is a lower limit switch (adjustable with a screwdriver via a temperature dial) that closes on temperature fall. On the top of the unit is a dual aquastat (both sides adjustable) in a squarish box. One side of the control functions as a high limit control (opens on temp rise, as a backup to the fan control) and the other is a dump zone control which closes on temp rise. The dump circuit controls the circulator, unlike the other controls which turn on/off power to the fan. There are other tappings in my boiler for the inlet, outlet, as well as the safety valve and the hot water coil. Whether there are more than that, hidden under the boiler jacket, I do not know.

Tull, you are correct. I was looking at the L4081B Aquastat incorrectly. There is indeed an available (unused) "close on rise" (normally open) switch that is present in this dual aquastat on the Coal Gun, just as you have stated. It is nominally listed as being a "Dump Zone Limit" switch, as this is the perfect use for it. It could be set up to start a circulator to a dump zone, or alternately if passed through a transformer it could be used to open a normally closed 24 VAC zone valve to a dump zone. That's perfect, as I will set it up to open up a zone valve at 210 degrees to my "first" dump zone (my homes largest single zone).

If there is in fact a free and unused immersion well tapping that is available I will install yet another dual aquastat to it and set up a "high/high" dump zone to another of my zones that is set 10 degrees higher at 220 degrees, and will open a zone valve to a "second" dump zone. That one will also be used for shutting off my circulator when the boiler temp. falls to or below 140 degrees.

Immersion wells come in both 3/4" and 1/2". Do the tappings on the AHS S130 have 3/4" or 1/2" threads?