Jump to content

Jandy Lx400 Hi Lim Sw Error


bigdog100

Recommended Posts

You are likely going to have to have a service call. Generally a Hi Limit problem is due to a flow problem through the heater rather than a problem with the switch. I'm not familiar with the Jandy heater, but most heater have a thermal regulator threaded into the heater manifold and it works similar to a thermostat in a car. Depending on the type of regulator, it could be simply that the spring (if so equipped)is not working (because it's been chemically damaged, debris stuck in it, etc), the regulator itself could be bad...trying to think of other possibilities.

In any case, probably not something you want to tackle yourself if you are not particularly mechanically inclined.

Link to comment
Share on other sites

  • 3 weeks later...

High limits on that heater are located directly under where the plumbing goes in and out. There will be two silver cover plates over with philips screws that hold the hi-lims in place. Each will have two white wires. Remove them and do a visual inspection. With polymer headers there will be a brass bolt/nut that transfers the heat from the water to the face of the limit switch. If the limits are corroded at all check to make sure that those brass bolts aren't leaking into the limit area. IIRC the bolts are still available, and the limits are certainly available.

Keep in mind, if the limits look fine, you can still check them for continuity with a meter. It is also possible that the wire has been broken. If the limits have actually had to perform their intended job they also have a life span. Jandy usually says about 10-12 cycles.

Link to comment
Share on other sites

  • 3 weeks later...
  • 2 weeks later...
  • 1 year later...
  • 2 weeks later...

The sensors are in the inlet/outlet housing underneath the 2 inch pipes. They are typically covered by a small stainless steel plate. You will see the white wires for them leave the housing and go into the heater cabinet. It is explained above. There is also another safety switch down by the burner assemble that looks like a resistor. It is supposed to detect if you have a flame roll-out but, sometimes this switch goes bad and becomes an open circuit. Most of these safety switches can be bypassed with a set of alligator jumpers as a method of diagnosis only. Do not leave any of the safety switches bypassed for obvious reasons!

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Unfortunately, your content contains terms that we do not allow. Please edit your content to remove the highlighted words below.
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...