Hydrolevel 700 Series User Manual
Low water cut-offs, Where to install, Probe installation
HOT WATER BOILERS: Probe must be installed at or
above the minimum safe water level established by the
boiler manufacturer. The probe may be installed directly
in the boiler (A) if a suitable tapping is available, in the
riser (B), in the header horizontally (C), or in the header
vertically (D). IMPORTANT: To assure proper drainage,
pipe diameter should be no less than 1" on installations
in vertical piping and no less than 1
1
⁄
4
" on installations in
horizontal piping.
WARNING: To prevent electrical shock or equipment damage, power must be off during installation or servicing of the control. To prevent
serious burns, the boiler should be thoroughly cooled before installing or servicing control. Only qualified personnel may install or service
the control in accordance with local codes and ordinances. Read instructions completely before proceeding.
TEE MOUNTING: If a field fabricated tee is used, make sure that the tee drains thoroughly when the
water level falls below it, and that it conforms to the spacing requirements described in Step 3.
Models equipped with the shorter EL1214-SV probe can be installed in most standard reducing tees.
Safgard cast iron tees are also available to accommodate all probe models (See page 4).
Loosen the two control box cover bind-
ing head screws and remove the cover.
Slide keyhole slots over probe mounting
screws and tighten screws (with either a
1/4" hex head driver or flat screwdriver.
Connect the ring terminal wire lead to the probe terminal
stud and secure with the lock washer and wing nut provided.
With the power removed, proceed with installation and
wiring according to Method A or B described on next page.
STEAM BOILERS (Secondary) : Control must be installed in a suitable tapping provided in
the boiler(A), or in an equalizing line(B). The control should be located below the level of the
primary low water cut-off but above the lowest permissable water line as specified by the
boiler manufacturer.
Note: For installations in equalizing lines, Hydrolevel recommends the use of Safgard Tees
(see step 2).
Low Water Cut-Offs
500 / 600 / 700 Series
24 VAC Operating Voltage
Automatically shuts off burner in a low water condition to prevent
boiler damage.
Low maintenance. No moving parts to wear stick or hang up, as in
float devices.
Test button (500 & 600 Series) allows the burner circuit and
control to be tested without lowering the water level.
Manual reset feature (500 & 700 Series) will not lock out in power
failures.
1. Where To Install
2. Tee Options
4. Control Mounting
3. Probe Installation
MINIMUM
WATER LEVEL
HOT WATER
BOILER
A
B
C
D
SECONDARY
LWCO
SECONDARY
LWCO
LOW WATER
CUT-OFF PUMP
CONTROLLER
LOW WATER
CUT-OFF PUMP
CONTROLLER
STANDARD
REDUCING TEE
(SV Models Only)
FOEM-TEE
(160psi)
1214C-2 TEE
(250psi)
FABRICATED TEE
TYPICAL STEAM BOILER
INSTALLATIONS
HOT WATER BOILER
INSTALLATIONS
A
B
Check to insure 1/4" clearance from probe to
any surface within the boiler or tee. When
installed in a tee, the probe tip should extend
fully into the pipe run. Apply pipe sealing com-
pound to threads.
Note: Use of Teflon tape is not recommended.