Fireman's switch ON when timer is OFF???

[vl]

I have Intermatic T104R201 to control pump/SWG and Pentair MiniMax NT with digital controls (on a circuit which is not controlled by timer switch).

For whatever reason fireman's switch was not wired to the heater by previous owner and entire setup was running 24/7. So I decided to wire it to save on costs.

To my surprise, heater detected "on" signal even when I flicked timer switch to "off".

After testing it for awhile it looks like fireman's switch goes back to "on" when timer lever goes fully to "off". Is this normal? This doesn't work for me since heater is not connected to the timer switch directly (and I like to have it on a separate breaker).

Proof is in the pudding, of course, so some pics:
ON - fireman's switch is on as expected


Intermediate - fireman's switch is off as expected


Off - fireman's switch is pass the bump on the lever and is ON AGAIN!

 

[JasonLion]

The fireman switch only turns off the heater during the startup and shutdown periods. The heater should turn it's self off when the pump is off.

 

[vl]

The fireman switch only turns off the heater during the startup and shutdown periods. The heater should turn it's self off when the pump is off.

Hmm, bad design though - it relies on fail-safe in the heater. What happens if pressure sensor in the heater fails? - entire heater goes caboom. Timer knows system is off and yet doesn't send the signal.

I wonder if electronic timers have control signal for the heaters that stays off when pump is off?
Could someone recommend a model?

 

[JasonLion]

If you are worried about it you should wire the heater to the same power as the pump. Then it can never be on unless the pump is also on. The fireman switch is specifically about the cool down period at the end of a cycle and nothing else.