train horn

i bought a 3pc train horn from a truck shop n for some reason it blasts wen my tank is at 100psi or lower.it uses a solenoid,is there a way to get a diff one or wat.

if you have a 10 switch box...run another valve like the ones you have for your suspension to it and replace your see-saw switch with a single switch (or where ever) and just use it like that.