14
TROUBLESHOOTING GUIDE
Table 14-1
DISASSEMBLY
Control Valve - All maintenance on the valve should be done by a factory trained product specialist
with the exception of replacing the pressure sensing diaphragm. To replace the diaphragm remove all nuts and
bolts from the bottom cover. After removing the bottom cover, remove the lock nuts from the bottom of the
valve shaft. You will need to hold the platter to prevent the assembly from spinning, or hold the stem with
large a slotted screw driver in the slot at the bottom of the stem. After removing the nuts, slide the platter off,
then the old diaphragm, being careful not to lose the brass washer above the diaphragm. To reassemble follow
the reverse order. Make sure when tightening the cover bolts that you use a criss-cross pattern.
Problem Causes Solutions
The steam is not turned on to the unit. Open steam valve to the unit.
The water tubes in the heat exchanger are
plugged.
See Clean-In-Place operating instructions or remove
tube bundle and clean.
The differential pressure sensing diaphragm
is ruptured.
Replace the diaphragm.
The mixing valve is not properly adjusted. Adjust the unit according to the instructions.
The steam pressure is too low. Increase steam pressure (2 - 15 psig).
Air has accumulated in the shell of the heat
exchanger.
Install a thermostatic air vent on the shell.
The flow is above the rated capacity of the
unit.
Make sure unit is sized properly.
The tubes in the heat exchanger are scaled.
See Clean-In-Place operating instructions or remove
tube bundle and clean.
The mixing valve is not properly adjusted. Adjust the unit according to the instructions.
The steam pressure is too high. Decrease steam pressure (2 - 15 psig).
Recirculated water is continually diverting
through the Flo-Rite-Temp.
Check diverting valve for a stuck or failed thermal
capsule.
The steam is superheated. Pipe to saturated steam.
The mixing valve is not properly adjusted. Adjust the unit according to the instructions.
The inlet valve on the water supply is closed. Open valve.
There is no demand for hot water. Wait till demand is present then re-check.
The shell of the heat exchanger is not
properly drained.
Make sure steam trap is working and properly installed.
Make sure shell is level to floor. Do not elevate
condensate if pressure is low.
The steam pressure has dropped or a
vacuum has formed.
Increase pressure and install vacuum breaker at shell
drain (Figure 1-1).
The water pressure had dropped below that
of the steam pressure and steam is forming
inside of the water tubes.
Install a pressure switch on water inlet to shut off steam
on a drop in water pressure.
The unit
hammers and
bangs during
operation.
Only cold water
comes out of
the unit.
Only warm
water comes
out of the unit.
Extreme hot
water comes
out of the unit.
No water
comes out of
the unit.