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[ralphxj]

I woke up to a cold house today!! OWB was humming along at 180*, all 3 zones calling for heat, but no water was being pumped! I tracked it down to the Honeywell L8124L triple aquastat on the oil boiler not sending any power to my pump. The way my system works the oil boiler is a backup, but the inside controls and everything still run through the aquastat on my oil boiler.

Is there anything I can do to fix the issue other then buying a new aquastat?? No one local has any (or they are closed till monday to even check) It's going to be COLD tonight and other then bypassing the wiring and plugging the pump into the wall and running it none stop, I have no way of heating the house???

[RSI]

Will the aquastat still fire the oil boiler or is it completely dead? Does the relay in the aquastat click when the thermostat calls for heat?

[ralphxj]

Boiler fires like normal and it clicks like it's working. It's only putting out 2.3 volts to the pump though instead of 120!!

[slimjim]

What terminals are you using? Is it your loop pump that supplies the heat exchanger? If so, plug it in and run it constant.

[ralphxj]

What terminals are you using? Is it your loop pump that supplies the heat exchanger? If so, plug it in and run it constant.

It's hooked to C1 and C2. This is for the house loop. It's currently plugged directly into the wall so I have heat. I have one of my zone valves manual opened so there was always water circulating.

[Trint]

Not familiar with that one looks a little different then mine, best I can say is try to test both sides of the relay and see if its working.  May be able to get a stand alone relay somewhere? If the burner fires I assume the transformer is good.

[ralphxj]

Figured it out!! It had to do with my low temp dial. I must have moved it too high and it messed something up. Not sure what happened, but some time with the multimeter and it seems to be working now.

Now to figure out how that thing works so I know how to set it correctly. Really should have made notes on what it was set at before I started the OWB install!! Anyone have any tips on setting the 3 dials for a normal oil boiler setup??

[slimjim]

The C-1 terminal powers up your circ on a call for heat  but only after the boiler high temp minus differential is achieved, typical temp settings are High 185. Low. 140 and 15 degree differential. Lots of people don't understand how this works so this is a good time to explain it.

High limit.   Shuts off boiler at setpoint

Differential.  On a call for heat with a 15 degree setpoint, the burner will fire at anything below 170, without a call for heat, nothing happens.

Low limit  without a call for heat in the house,the burner will fire at any temp below the setpoint in order to protect the domestic water temp.

This control is typically used on less efficient boilers with a domestic water heat coil installed into the water jacket, it is not used on high efficiency cold start,low water volume boilers with an indirect hot water tank.