RIMS for Dummies Wiring Questions

So I've been through most of the wiring threads on HBT and have accumulated a lot of information -- thanks to everyone who contributed to those threads. I do have a couple of questions that I couldn't quite figure out and am hoping for some input. I'll be using the SYL-2352 PID, 20 Amp SSR, March pump, 1500 watt 120v heater element and 15 amp service. When all is on, I know that's pushing the 15 amps a little but I really don't have another option at this point. I'm also thinking about adding a .25 amp fast blow fuse to protect the PID, though please give me your thoughts on that. Have thought about a slow blow fuse for the pump but I think I'm going without that.

Question about the size of wire. I had planned on using 14 gauge wire for everything consistent with the 15 amp service. But I read in one of the threads that it's possible to use 22 gauge wire from power source to PID to SSR. Will that work? If so, what size wire would I run from the SSR to the element?

I'm also having trouble sourcing a fuse holder for the .25 amp fuse that will accept 14 gauge wire, which also suggests to me that I'm missing something.

Lastly, I'd like to add a light that lights up when the element is on. Looking at some diagrams, looks like the light just goes inline between the element and the SSR. Is that right?

Thanks for any help you can provide.

I would definitely fuse the PID. As for the pump, as long as your wiring between it and your breaker is sufficient enough, then you shouldn't need a fuse as the breaker would be your safety.

22ga would probably work fine considering that the PID and SSR will pull very little power. This is of course assuming that you're only wiring the coil side of your SSR with the 22ga and not the load side. I think I would still just wire it with something thicker than that though just for peace of mind, however. For the amount of wire that you'll be using, it's not like you'd be saving a whole lot by going to a smaller guage anyway. 14ga should be okay for the load side of things. But I'll let someone else chime in just in case that's incorrect. I'm pretty sure though that 14ga is good for 15a without a problem and your 15a breaker would trip before the wire melted.

Have you considered an in-line fuse holder? That should work fine. You could also step it up to .5a or even 1a and still have a well protected PID.

You don't want to run the power for your element through the lamp (or inline) as that will treat your lamp as a fuse and most likely blow it out real quick. So just run two wires off of your SSR, one to the element, and one to your lamp. Run the neutral for the lamp back to your negative bus.

Thanks Dave. I think I get it now -- I didn't appreciate the distinct operations of the load side versus the coil side of the SSR (scary I know). I have looked at in-line fuses/holders and will do that -- I just hadn't found one that would take the small .25amp fuse and accept 14 gauge wire. I have seen them with 18 gauge wire, which addresses your other point and should work well. I get what you're saying about the lamp and will do that. Thanks again!