Pentair 42002-0025S Replacement 140F Automatic Gas Shutoff (AGS) Switch | Design for Pool & Spa Heater | Easy Installation Pool Maintenance Kit & Accessories | 18-Month Warranty & USA Support

My Pentair 400 series pool water heater shut down with a service lamp on that presented me with a challenge to figure out what happened. Removing the front and back panels of the heater allows access to 4 wing nuts that will allow removal of the top section. By doing those steps it is possible to look at the backside of the touch panel control board, where you should see a red lamp lit up, at one of four fault codes, that will identify the general fault area causing the problem. Mine had the 'AGS' lamp on, which meant the 'Auto Gas Shut Off' sensor failed. Gaining access to this switch required removing the side water in and out panel and installing this new sensor. It worked like a charm and I avoided having to pay a service tech to come out, who by the way mentioned he was three weeks out to check out my heater in the forst place. This aftermarket part is reasonably priced and works perfectly to restore a AGS lamp fault code, that will get your system up and running in short order.

Install new part working great

Well made and priced.

Great replacement.

Great product, arrived on time and at a fair cost

Installed part and it resolved the problem of heater not firing.

does its job as described. no issues

My pool heater was throwing off an error - AGS and did a little research and decided to try this part as the fix. installed it, turned it back on and it now heats. So a $21 part saved a larger service call!

Delivered on time and was a drop in replacement for the OEM part at more than half the cost