Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.
Laars Endurance issues

kcopp
Member Posts: 4,305
in Gas Heating
Having an issue w/ a Laars endurance Combi boiler. Nat Gas.
Customer complains about inconsistent hot water output... also was/ is getting the F4 error.
Manual says to swap out the sensor in the boiler (2400-445) I did that and still the issues persist.
Issue also appears to be intermittent... Runs fine when I am there then shows up later.
This is the newer version grey/ gold jacket.
Customer complains about inconsistent hot water output... also was/ is getting the F4 error.
Manual says to swap out the sensor in the boiler (2400-445) I did that and still the issues persist.
Issue also appears to be intermittent... Runs fine when I am there then shows up later.
This is the newer version grey/ gold jacket.
0
Comments
-
Did you ever resolve the issue? I am getting an intermittent F4 error. This is accompanied by a banging noise and the pressure gauge jumping up and down. I turn the unit off and on and the problem goes away. I have tested the sensor with an ohmeter and it tested good (1.4K ohms). I am wondering if the sensor is only failing when it gets hot inside the unit.0
-
-
I am suspecting insufficient water flow causing the water to flash boil and the high temperature of the water causing the sensor to go out of range. I measured the amperage of the system pump and it is double what it is supposed to be. So, I am leaning towards changing it.0
Categories
- All Categories
- 84.7K THE MAIN WALL
- 3K A-C, Heat Pumps & Refrigeration
- 54 Biomass
- 421 Carbon Monoxide Awareness
- 58 Chimneys & Flues
- 1.8K Domestic Hot Water
- 5K Gas Heating
- 124 Geothermal
- 158 Indoor-Air Quality
- 3.2K Oil Heating
- 57 Pipe Deterioration
- 830 Plumbing
- 5.6K Radiant Heating
- 373 Solar
- 14.3K Strictly Steam
- 3.1K Thermostats and Controls
- 55 Water Quality
- 42 Industry Classes
- 83 Job Opportunities
- 24 Recall Announcements