Can't lower temperature of Honeywell L4103A 1019

awf1130 · 03-09-2013, 09:40 AM

I'm having trouble lowering the temperature on my Honeywell L4103A 1019 Aquastat. I've gotten some help on other forums, including the plumbers forum on DIY, but someone there suggested I try here. I've found this documentation on the aquastat, but as you can see from the picture of mine, it's slightly different and the diagram in the doc doesn't do a great job of labeling the different parts.

I'm not really familiar with the terminology, but from the documentation I understand there is a factory-set setpoint - which is set by the factory and cannot be changed and an adjustable temperature setting scale (also referred to as a setpoint), which is the high temperature at which I would like the burner to shut off. And the solution in this post suggests that I need to set the low temp first and the high temp second, and then let it cycle through a few times.

Here's what I'm still trying to figure out:

In my photo, is #3 the marker for the lower or high temp?

What does the little lever (#2) do, is that for the lower or high temp?

The dial lists both warm/normal/hot as well as what appears to be actual temperatures (although all but one is faded). Which do I use for setting the temperatures that I want?

Here is my original post. Thanks for the help.

**beenthere** · 03-09-2013, 11:06 AM

3 is the indicator of whee you have the temp set to. Already set low in the pic. Is your water steaming, or do you just want to set it lower for vacation.

awf1130 · 03-09-2013, 04:37 PM

Quote:

Originally Posted by beenthere

3 is the indicator of whee you have the temp set to. Already set low in the pic. Is your water steaming, or do you just want to set it lower for vacation.

My water is steaming... probably up around 150 or 160 degrees.

**beenthere** · 03-09-2013, 05:35 PM

If its steaming with where you have the temp set, then either the control's well is coated with minerals which are insulating it, or the control is bad. If the well isn't coated, then the control needs replaced.

how · 03-09-2013, 05:47 PM

Is this residential boiler control. Details???
Usually there would also be a second aquastat. The first one being the operating control with the second one being a higher limit control.
Typically the thermostat would turn on the gas and pump. This control is just controlling the water temp by turning off the gas valve.
If the temp listed is 150 to 160 Fahrenheit, then that is normal. If you start operating a boiler lower than 140 that you'll end up with exchanger condensation, rust & scale.
Where is it steaming?
Could you explain why you wish to turn it further down?

**beenthere** · 03-09-2013, 06:16 PM

Oil fired water heater.

awf1130 · 03-09-2013, 09:18 PM

Quote:

Originally Posted by beenthere

Oil fired water heater.

How, that's correct, it's a TFI Therma-Flow Everhot Oil-fired Water Heater. And from what I understand, there is a factory-set setpoint that cannot be changed, as well as the high and low variable temp setpoints. 150-160 degrees is an estimate - it's hot enough to be melting the plastic tips on the racks of my dishwasher. More importantly, it's way too hot with two little kids in the house.

Beenthere, is it easy to check to see if the control's well is coated with minerals? Thanks for the help, appreciate it.

**beenthere** · 03-09-2013, 09:34 PM

Drain water heater. Disconnect wires and screw it out and examine it.

03-09-2013, 09:40 AM	#1
awf1130 Newbie Join Date: Mar 2013 Posts: 9	Can't lower temperature of Honeywell L4103A 1019 I'm having trouble lowering the temperature on my Honeywell L4103A 1019 Aquastat. I've gotten some help on other forums, including the plumbers forum on DIY, but someone there suggested I try here. I've found this documentation on the aquastat, but as you can see from the picture of mine, it's slightly different and the diagram in the doc doesn't do a great job of labeling the different parts. I'm not really familiar with the terminology, but from the documentation I understand there is a factory-set setpoint - which is set by the factory and cannot be changed and an adjustable temperature setting scale (also referred to as a setpoint), which is the high temperature at which I would like the burner to shut off. And the solution in this post suggests that I need to set the low temp first and the high temp second, and then let it cycle through a few times. Here's what I'm still trying to figure out: In my photo, is #3 the marker for the lower or high temp? What does the little lever (#2) do, is that for the lower or high temp? The dial lists both warm/normal/hot as well as what appears to be actual temperatures (although all but one is faded). Which do I use for setting the temperatures that I want? Here is my original post. Thanks for the help. Attached Thumbnails

03-09-2013, 05:35 PM	#4
beenthere An old Tradesmen Join Date: Oct 2008 Location: PA Posts: 19,065	Can't lower temperature of Honeywell L4103A 1019 If its steaming with where you have the temp set, then either the control's well is coated with minerals which are insulating it, or the control is bad. If the well isn't coated, then the control needs replaced.

03-09-2013, 05:47 PM	#5
how Member Join Date: Feb 2011 Location: Vancouver BC Posts: 1,416	Can't lower temperature of Honeywell L4103A 1019 Is this residential boiler control. Details??? Usually there would also be a second aquastat. The first one being the operating control with the second one being a higher limit control. Typically the thermostat would turn on the gas and pump. This control is just controlling the water temp by turning off the gas valve. If the temp listed is 150 to 160 Fahrenheit, then that is normal. If you start operating a boiler lower than 140 that you'll end up with exchanger condensation, rust & scale. Where is it steaming? Could you explain why you wish to turn it further down?

03-09-2013, 06:16 PM	#6
beenthere An old Tradesmen Join Date: Oct 2008 Location: PA Posts: 19,065	Can't lower temperature of Honeywell L4103A 1019 Oil fired water heater.

03-09-2013, 09:34 PM	#8
beenthere An old Tradesmen Join Date: Oct 2008 Location: PA Posts: 19,065	Can't lower temperature of Honeywell L4103A 1019 Drain water heater. Disconnect wires and screw it out and examine it.

Can't lower temperature of Honeywell L4103A 1019