Intermatic Timer Replacement ... How do I find model number I have? What's that other thing?

[Leonian]

I have a pair of Intermatic timers regulating my pool pumps. One timer controls my pool pump for the filter, the other controls a booster pump for my Polaris cleaner. The yellow dial on the filter pump (your left in the attached photo with the two dials) no longer works. I can see gears move on the timer motor (in the back of the timer), but the yellow dial with the time markings doesn’t rotate. I have no problem if I pull on the dial and want to reset the time, but once set, the time does not change.

It was thinking I should replace this timer. My questions:
1) What model do I have? I can’t seem to find that information on the timer.
2) What does that thing in the lower right corner of the left timer do? It is not present on the right timer. Will the presence of this thing complicate my replacing the timer?

Thank you in advance for your help

 

[JamesW]

It's a T32404R timer.

The bad part is T104M201. That includes the fireman's switch. The other timer is a
T104M, which doesn't have the fireman's switch. If you don't need the fireman's switch, you can get the T104M timer mechanism.

https://www.intermatic.com/pool-and-spa/mechanical-controls/t32404r

The thing on the left timer is a fireman's switch, which turns off a gas heater about 15 minutes before the pump turns off.

 

[ajw22]

The thing on the right corner of the left timer will turn off a heater 20 minutes before the pump turns off. It cools down the heater before the pump shuts off.

 

[Leonian]

Thank you for your responses. They were most helpful.
I've ordered a T104M201 to replace my inoperative one.
I'm glad I asked about that thing that is the fireman's switch. I had never noticed that the heater shuts off before the pump. Then again, the heater hasn't been working since last summer ... but that's another project. My first order of business is to get the pump timer working.

Thanks again.
TFP is a great resource.