Honeywell L8148E Issues

tcassano87

Have a Peerless Hydronic Boiler with a Honeywell L8148E Aquastat relay, it also uses a Nest Themostat with 2 wires for references. It has a pilot, Damper opens, boiler kicks on but not sending power to the circulator. Tested C1/2 not getting 110, but power is obviously coming in. Forgot to take a picture of the inside of the relay but my feeling is I have a bad Relay cause it’s not sending power to the circulator.
don’t believe that secondary Aquastat is an issue cause it’s set incredibly high and insanely high limit. LWC isn’t even hooked up

tcassano87

also curious if there is a true difference between a

Honeywell Aquastat L8148E1257

Honeywell Aquastat L8148E1265

$200 price difference cause the first one has a vent damper damper connection but don’t see any noticeable difference between on the internal parts besides the white flap and the number on the transformer

109A_5

Hello tcassano87,

There is a relay in the L8148E Aquastat that does the switching, It could be bad, it is quite common IMO that the solder joints that connect the relay to the circuit board fail. They can be repaired by someone skilled in that type of repair or the L8148E Aquastat may need to be replaced to resolve your issue.

Sometimes flexing the circuit board or side pressure on the base of the relay with a nonmetallic insulated tool can verify the issue.

EdTheHeaterMan

You are not supposed to get 120 VAC at B1 and B2. You are supposed to get 24 VAC on your L8148E

But don't replace it with the same control. After your are sure that the control is defective get an electronic control. But first make sure the control is really defective and not some other part of the system.

L8148A is for oil heat and has 120VAC at B1 and B2.

I believe you have a 24 V gas valve that is connected to B1 and B2

109A_5

Not sure what the different is besides the price.

EdTheHeaterMan

This Hydrolevel 3200 control will do the same job and is less expensive

tcassano87

https://forum.heatinghelp.com/discussion/comment/1832589#Comment_1832589

didn’t see that thank you, sometimes the obvious is right there lol

tcassano87

I have 110 coming in, didn’t say anything about B1, that I know send 24v to the gas valve

EdTheHeaterMan

https://forum.heatinghelp.com/discussion/comment/1832599#Comment_1832599

Sorry, I read it wrong. The C1 and C2 should send 120 VAC out. sometimes a solder joint needs to be corrected on the under side of the control as @109A_5 suggested…. If you still believe the control is defective then use this Hydrolevel 3200 as your replacement. It is less expensive that any of the L8124 controls. Look inside… it has all the same wire terminals and plug for the vent damper.

tcassano87

https://forum.heatinghelp.com/discussion/comment/1832593#Comment_1832593

great to know thank you for your help

EdTheHeaterMan

In order to verify that the relay is the problem, You can try to connect the circulator directly to 115 VAC. if the heat from the boiler starts to move thru the pipes, then you know the circulator is good. Once you determine that the circ. pump is working you then try the wiggle thing on the actual relay part of the control when there is a call for heat, suggested by @109A_5. If you can't get the relay to click in on a call for heat then you have a bad L8148E aquastat relay. If the relay pulls in as it should, and the burner operates as it should, then you may have a bad solder connection on the Neutral from the relay to the C2. If that is the case, then you can get the neutral for the circulator pump from the L2 terminal. If that solves the problem, then you are done. Just leave the L2 wire and the C2 wire under the same L2 screw. That is an acceptable final permanent repair.

tcassano87

https://forum.heatinghelp.com/discussion/comment/1832593#Comment_1832593

https://forum.heatinghelp.com/discussion/comment/1832704#Comment_1832704

great to know thank you that’s a good idea with the neutral, I do know the circulator is fine cause I switched it out for a brand new just to made sure since I had one with me and it takes a couple minutes.

EdTheHeaterMan

I do know the circulator is fine cause I switched it out for a brand new just to made sure since I had one with me and it takes a couple minutes.

Read my tag line. You can verify the old pump is working without replacing it with a new pump. I hope you had isolation valves before and after the pump so you didn't need to drain the entire system.