Baxi Slim, does not work without a thermostat

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Baxi Slim, does not work without a thermostat

Postby Jager » Sat May 12, 2018 5:50 pm

With a thermostat, everything works well.
With a jumper instead of a thermostat when sending the command CS=XX a flag is set central heating enable (CH=1)

but the burner does not turn on, experienced to find out that the burner is activated only if the flag is activated central heating mode

When operating from a thermostat, the flag central heating mode active.
The question is how to activate central heating mode forcibly?
Thank you
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Re: Baxi Slim, does not work without a thermostat

Postby hvxl » Sat May 12, 2018 8:58 pm

You're confusing cause and effect. The Central heating mode flag is reported by the boiler to indicate the burner is activated, not the other way around. Perhaps the CS value you provided is just not high enough. But unfortunately you didn't mention what you used.

Also the two pictures you include both show Central heating enable and Central heating mode active. So those seem to be from a working situation. It is usually most helpful to provide some information for the non-working situation. Due to this lack of information I cannot make any useful suggestions.

Note: You are either expected to put a jumper instead of a thermostat, or use the CS command. I have no idea what happens when you do both at the same time. It never occurred to me to try that.

If you want me to look into this, please remove the jumper, run a CS=0 command, and let the boiler sit for a few minutes to allow any anti-cycle timer to run out. Then issue a CS command with a sufficient high value (e.g. CS=70). Collect the OTmonitor log from a few minutes before until a few minutes after the CS command and upload that somewhere or attach it to your post.
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