Peltier Fridge?

I'm currently a novice with Arduino, and have little programming experience, and need some help with efficiency, and where to go from here.
Currently, I've got it to log temperature from a 100k Thermistor, and if the temperature is at or above 38 degrees Fahrenheit it turns on a Solid State Relay controlling a peltier unit inside a small insulated box, and once it is at or below 36 degrees Fahrenheit, it turns the peltier unit back off.
However, I tried to make it flash a warning led of red letting me know that the temperature is above 40 degrees Fahrenheit, and the peltier unit didn't activate.
As this is my first code, I figured I'd have some problems.
here's my code, any help with efficiency, ect. would be greatly appreciated.

#include <math.h>

int pinOut = 10;

double Thermistor(int RawADC) {
  double Temp;
  Temp = log(10000.0 * ((1024.0 / RawADC - 1)));
  Temp = 1 / (0.001129148 + (0.000234125 + (0.0000000876741 * Temp * Temp )) * Temp );
  Temp = Temp - 273.15;
  Temp = (Temp * 9.0) / 5.0 + 32.0;
  return Temp;
}

void setup() {
  Serial.begin(9600);
  pinMode(10, OUTPUT);
  pinMode(7, OUTPUT); //Green Led = On
  pinMode(8, OUTPUT); //Red Led = Error
  pinMode(2, OUTPUT); //Blue Led = Standby
  //pinMode(4, OUTPUT); //Buzzer (Unused pin)
}

void loop() {
  int val;
  double temp;
  val = analogRead(0);
  temp = Thermistor(val);
  Serial.print("Temperature = ");
  Serial.print(temp);
  Serial.println(" F");
  if (temp >= 38) {
    digitalWrite(pinOut, HIGH);
    delay(1000);
    digitalWrite(7, HIGH);
    delay(1000);
    digitalWrite(7, LOW);
  }
  else {
    if (temp <= 36) {
      digitalWrite(pinOut, LOW);
      digitalWrite(2, HIGH);
    }
    else {
      if (temp >= 40) {
        delay(1000);
        digitalWrite(8, HIGH);
        delay(1000);
        digitalWrite(8, HIGH);
      }
    }
  }
  delay(500);
}

Temp isn't going to be 40 at that its 26k ohms if you have a divider with say 10k to five volts it's center reading will be 736 so your cooler is just kicking on and off at your first two setting.
And like post 1# you need a elseif you have error or use a case statement.