(f) Connect wires to terminals
pressure temperature control (fig. 4-37B).
(m) Tighten compression fitting packing
(g) Reconnect aluminum tubing line to
(3) Test Operation.
(h) Insert 3/8 IPS x 1 inch long pipe
(a) Operate water pump and check all
nipple into header connection previously used for
connections for water leaks.
temperature control bulb.
(b) Connect fuel and electrical supply
(i) Thread 3/8 IPS x 1/2 inch IPS
reducing ell onto nipple.
(c) Turn fuel pump motor switch on and
(j) Remove 1/2 inch pressure relief
check fuel lines for leaks.
valve and street ell from header. Street ell will not be
required with new arrangement. Reinstall the pressure
(d) Open fuel shutoff valve and fire
relief valve in the 3/8 x 1/2 inch reducing ell.
heater at maximum firing rate (100 PSIG pressure on
fuel pressure gauge).
(k) Attach drain line to discharge of
pressure relief valve.
(e) Observe water temperature gauge.
Fuel solenoid valve will be de-energized when water
(l) Using compression fitting, install
temperature reaches a temperature of about 120F.
temperature bulb into connection previously used for the
pressure relief valve (fig. 4-37C).
energized when water temperature is 90F.
Figure 4-37. Installation