I tried setting the HI at 220 and LO at 190. But you're right that there are a few things to worry about besides having to keep the boiler hot for the tankless coil used to produce domestic hot water for washing and bathing. It's slightly more complex: heating up an ice cold boiler may force the burner to run at less than optimum efficiency for a longer part of its burn cycle than otherwise. You will want to take a look at other measures for improving hot water quantity such as flow restriction or going to an indirect fired water heater. AQUASTAT RESET BUTTON at InspectApedia.com - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice. This point is at the top of the yellow in our illustration. hot water by air. On 2020-04-16 by Anonymous In my case this is ~ 185, after observing a number of cycles. My understanding is that the WMO-1 should be in between B1 of the aquastat and the LIMIT port on the R7284U. And everyone felt smug about saving on heating cost. What does that mean? Im looking for info on wiring a new Honeywell oil control to my old arcoliner furnace with the arcoflame oil burner [Photo above], TomLet's start with the diagnostics at CIRCULATOR PUMP WON'T START https://inspectapedia.com/heat/Circulator_Pump_No_Start_Repair.php, t-stats work boiler or circulation pump do not. Thanks again. I have an oil fired boiler with a tankless coil installed. As Damian [image] pointed out in email, that's a mistake if you want as much hot water as possible out of your tankless coil. [As in case 1 above, this "burner-off" may be over-ridden and the burner may be turned "on" IF at the same time the room thermostat is calling for heat.]. Watch out also: if your heating boiler is oil fired in particular, I'd be sure to have it cleaned at the end of the heating season; when you disable the LO on the aquastat the boiler never runs all summer (which I like) but if the boiler was left sooty, condensation over the summer can glaze and thus petrify the soot inside the boiler making it tough to clean; if you have the boiler cleaned at the end of the heating season, while the soot is still soft and fresh, cleaning is easier. I would ask for an inspection by your heating service tech to decide: 1. what's causing the system to go off on re-set. It would seem that this would bypass the the Aquastat, allowing the second zone circulator to move cold water through the system. The tankless coil is on the heating boiler. Yes. My heater green light blinks. 11/26/2013. - Honeywell Aquastat L4046H HI-LIMIT controller. We took the cover off the Aquastat(L8124A) and saw a semi exposed wire and the circuit board looks like it been arced. Apologies for the delay. We call the LO the the "circulator lockout" control or the "tankless coil control" to try to make this more clear. We have no relationship with advertisers, products, or services discussed at this website. water temperature is below High Limit setting. Join Date: Oct 2013. Should I be turning the heat off in the house before I shower? On 2020-09-24 by (mod) - Watch out: it's not always the "blue" wire - see the Honeywell L8124A Aquastat Wiring Details. Thanks for reading and if you have some other ideas would appreciate your comments. If you do not disconnect the "LO" limit switch Is this correct? But they've got a point - it's the safe answer though not the most economical one. This gives more even heat and helps avoid a frozen heating zone pipe in very cold climates. Or use the SEARCH BOX found below to Ask a Question or Search InspectApedia. I have an Oil Fired Boiler forced hot water system (Hydronic) with typical baseboard radiators. About your "... shower is in another heating zone ..." - I'm a bit confused. Not sure if arcing mark is from close proximity to exposed wire or damage to board. Apologies for the delay. Only wire on L8124A aquastat was the Lo blue wire disconnected but as soon as it was reconnected the burner started. During warm months when the boiler is not being called-on to heat I would in most cases as the indirect hot water heater is probably running as if it were its own little separate heating zone. off, and the Aquastat Controller locks out. However it is TRUE that IF we are enjoying a nice hot shower and a heating zone calls for heat, turning on the circulator (or opening the zone valve) for that zone sends a blast of cold water (from the cold radiators or baseboards) back into the boiler, dropping its temp and thus reducing heat for the tankless coil and for your shower). An exactly correct answer to this question requires either some theoretical calculations for your particular boiler, burner, and the gph or BTUh rate of the burner along with the thermal mass of the boiler. On boiler temperature rise up to 155F the circulator is turned ON (or is allowed to turn on) and the burner is turned OFF. This topic has moved to a separate article. It may be necessary to manually open the flow-control valve or check valve (shown above) in for hot water to flow. How do I reconnect the bypass to enable the use of the multi-fuel boiler. disconnected entirely - it's simply a matter of removing a jumper wire (usually the blue wire pointed-to by our pen in the photo at below left, next to the DIFF control. Our photo shows an older aquastat type primary controller on an oil fired heating boiler. Try the search box just below, or if you prefer, post a question or comment in the Comments box below and we will respond promptly. And that's not always desirable. It has a honeywell R7284U Oil Primary, a Honeywell L8124AC aquastat, a power vent, and a Field Controls WMO-1 200 flue blocked vent switch. You can set it down to its lowest setting and if you are not going to disable the LO - which is not needed when there is no tankless coil, you could set that down lowest as well. The LO must be set at least 20 deg F. below the "HI" limit on a combination We discuss all of these controls in detail below.See RESET SWITCH on PRIMARY CONTROL. Here we reiterate the explanation above, trying a little different approach that may help some readers. Honeywell R7184 Series Primary Controls Technicians Quick Reference Guide, Honeywell L7224U Oil Electronic Aquastat Controller, Honeywell L8124A,B,C,E,G,LO,M Aquastat Relays, HOME INSPECTION EDUCATION COURESES (Canada), HOME INSPECTION EDUCATION: HOME STUDY COURSES. If you are referring to the reset button on an oil fired heating system most likely the problem is with the oil burner: an inadequate or faltering flame. How to Remove Google FRP lock on any phones 2017 trick - Duration: 5:53. DIFF specifies the number of degrees above the LO setting at which the burner will turn OFF and the circulator will be allowed to turn ON when the burner has been on and water temperature in the boiler is rising. Above: I'm pressing the reset button on the actual reset switch inside the aquastat of a heating boiler. At similar woodstove-heated homes where a hydronic boiler heating system was installed, we found that the woodstove could keep the room containing the heating thermostat warm enough that the boiler would virtually never run. Or use the SEARCH BOX found below to Ask a Question or Search InspectApedia.