Need timer advice

[coilerman]

I was thinking of adding a timer to my pump and heater circuit and read that some of the Intermatic timers have a feature whereby the heater shuts off 20 minutes before the pump. "Eliminates the problem of pounding and knocking due to overheated water, reduces scale and lime deposits and extends the service life of the heater."

How important is this? I have a Hayward H350 gas heater.

 

[JasonLion]

Some heaters absolutely require a fireman switch, some really don't care. Nearly all heaters will last longer if they are they are turned off before the pump turns off, only a few will outright fail. If I remember correctly the H350 is a heater that does not require a fireman switch but will most likely last longer if you have one.

 

[budster]

The T101PR201 or T104PR201 will get you there.