Install Instructions

5
TROUBLESHOOTING
Burner Will Not Fire See Flow Chart 1, page 6
Burner Will Not Shut Down See Flow Chart 2, page 7
Temperature Display Exceeds
High Limit Setting
Under normal operation, boiler temperature will continue to rise after the control shuts off
the burner. This condition, known as “thermal stacking”, results from hot boiler surfaces
continuing to release heat into the boiler water.
No Domestic Hot Water
Make sure the low limit setting on the HydroStat is set properly. NOTE: If the low limit
setting is dialed fully counter clockwise, it will shut off the low temperature maintenance
feature and will function as a cold start control. If boiler is operating in conjunction with
an indirect water heater, check to be sure the temperature control on the indirect tank is
set properly. Make sure any valves in between domestic hot water heating device, boiler,
and hot water taps are open.
Boiler Will Not Maintain
Low Limit Temperature
Check for overlapping high temperature setting. If the high limit setting is set below the
low limit setting, the control will default to the high limit setting and the corresponding
high limit differential setting.
Temperature Display
Differs from Boiler
T&P Gauge Temperature
Reading
Temperature variances can result from differing water temperatures within the boiler or
different reaction times of the two devices. If the HydroStat temperature is significantly
below the T&P gauge temperature, make sure the thermistor is inserted all the way to
the end of the well. If installed in an existing conventional well, check that hardened heat
conducting grease has not impeded the insertion of the thermistor. Clean or replace the
well to ensure proper insertion of the sensor.
LWCO “Active” Light
(Green LED) Is Not On
The HydroStat will only provide low water cut-off functionality when used in conjunction
with an insulated Electro-Well™. When attached to a standard immersion well, the
LWCO “Active” light will remain off and the HydroStat will provide temperature
functionality only.
Low Water Light
(Red LED) Is On
WARNING: A low water condition is a serious and potentially dangerous condition. Do
not attempt to add water to a hot boiler. Allow the boiler to fully cool before adding water.
1. If the heating system is filled with water, pull the sensor out of the well and inspect it.
Make sure that the metal clip on the sensor is intact. This metal clip must be in contact
with the inside of the copper well in order for the control to sense the presence of
water. Check that the well does not have excessive build-up of heat transfer grease
that may interfere with clip contacting the well.
2. Remove well and examine for excessive residue build-up. Clean and re-install.
LED LEGEND

TEMP ACTIVE Indicates that the HydroStat control is
powered and that the temperature function is active.

TEMP HIGH TEMP Illuminates when the boiler water
temperature reaches the high limit setting. It will remain lit
until the water temperature falls below the high limit setting
less the differential setting.
The HydroStat control will prevent burner operation while this
LED is on.
NOTE: This LED illuminates regularly during normal boiler
operation.

LWCO ACTIVE Indicates that the low water cut-off
(LWCO) function of the HydroStat control is active. When the
control is installed with a Hydrolevel Electro-Well, this LED
will be on at all times when the control is powered.
NOTE: If the control was installed with a well other than the
Electro-Well, this LED will not illuminate. This indicates that
the control is providing temperature function only.

LWCO LOW WATER Indicates that the boiler is in a
low water condition. The HydroStat control will prevent burner
operation during this condition.
IMPORTANT:
The system must be checked by a qualified heating
professional prior to resuming operation.
WARNING: ALLOW THE BOILER TO FULLY COOL
BEFORE ADDING WATER.