1. WATER HEATER DOES NOT HEAT WATER
Step 1. 24 vdc is not available from pump unit.
Troubleshoot pump unit. See malfunction 5,
Step 2. Check for defective thermostatic switch S1
using the following procedures:
a. Remove TD2 tube from its socket.
Check from TD2 socket, hole 7, to switch
static switch S1 in top of the boiler is bad.