Hydrolevel 3100 User Manual
Warning, Caution, Hydrostat installed with electro-well
83 Water Street • New Haven, CT 06511 • Phone (203) 776-0473 • FAX (203) 773-1019 •
Combination Low Water
Cut-Off & Universal
Temperature Limit Control
for Gas Boilers
Electrical shock hazard. To prevent electrical shock, death or
equipment damage, disconnect power supply before
installing or servicing control. Only qualified personnel may install or service this control in
accordance with local codes and ordinances. Read instructions completely before proceeding.
To prevent serious
should be thoroughly cooled before installing or
• Dual Function Design – HydroStat performs both high temperature limit and low
water cut-off functions when installed with a Hydrolevel Electro-Well™.
• Replaces Common Aquastat
Models – Can be installed on existing immersion
wells to replace both cold-start and triple-action Aquastats
. Industry standard
wiring designations make change-outs quick and easy.
• Digital Display – Easy to read LED continually displays boiler temperature. Also
displays temperature limit and differential settings during adjustment.
• Easy to Set – Dials for setting temperature limits and differentials eliminate
• Advanced Micro-Controller Design – Utilizes dual thermistor technology for
better accuracy, response and reliability.
*Aquastat is a registered trademark of Honeywell International, Inc.
When installed with the Hydrolevel Electro-Well,
HydroStat will provide
both temperature and low water
cut-off functionality. If the control was supplied by the
boiler manufacturer, it was installed with an Electro-
Well. The Electro-Well is available separately for field
installations. See Electro-Well models on page 8.
When installed on a standard immersion well, HydroStat will not provide low water cut-off functionality.
HydroStat installed with
a standard immersion well
For field replacement of common Aquastat
HydroStat can be installed with the immersion well
already on the boiler. In this configuration, HydroStat
will provide the temperature functionality of the control
being replaced, but will not provide low water cut-off
functionality. The “LWCO Active” LED will not illuminate.
For proper opera-
tion of the low
water cut-off func-
tion, there must
be a minimum of
between the cop-
per well tube and
any surface within