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.
Honeywell L7224U controller Err 5

Swilliam
Member Posts: 1
in Oil Heating
Just replaced my L7224U controller because the old one got fried when using a portable generator. So I simply put the wires back in the same positions in the new unit. But I get an Err 5 code, which means "Low Line; check L1-L2, 110Vac" There is 121 V across the L1 and L2 wires, same as for the rest of the house. Any ideas?
0
Categories
- All Categories
- 86.7K THE MAIN WALL
- 3.1K A-C, Heat Pumps & Refrigeration
- 55 Biomass
- 423 Carbon Monoxide Awareness
- 102 Chimneys & Flues
- 2K Domestic Hot Water
- 5.6K Gas Heating
- 102 Geothermal
- 158 Indoor-Air Quality
- 3.5K Oil Heating
- 68 Pipe Deterioration
- 935 Plumbing
- 6.2K Radiant Heating
- 384 Solar
- 15.3K Strictly Steam
- 3.4K Thermostats and Controls
- 54 Water Quality
- 43 Industry Classes
- 47 Job Opportunities
- 17 Recall Announcements