Honeywell aquastat l8124c User Manual

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1. Read these instructions carefully. Failure to follow 

them could damage the product or cause a 
hazardous condition. 

2. Check the ratings given in the instructions and on 

the product to make sure the product is suitable for 
your application. 

3. Installer must be a trained, experienced service 

technician.

4. After installation is complete, check out product 

operation as provided in these instructions.

Electrical Shock Hazard.
Can cause severe injury, death or equipment 
damage.
Disconnect power supply before beginning 
installation to prevent electrical shock or 
equipment damage.

Bend the tubing, if necessary, to hold the bulb against the 
bottom of the well. Do not make a sharp bend in the 
tubing. A sharp bend can produce a break in the tubing 
and cause loss of fill. This condition will cause the high 
and low limit controllers to be continuously made.

Select models have an adjustable capillary length. 
See Fig. 1.

Each relay is suitable for use with an immersion well for 
insertion into the boiler. (Check individual OS number 
specifications to determine whether a well is supplied 

with the relay.) Refer to form 68-0040, Wells and Fittings 
for Temperature Controllers, to order well. A compression 
fitting is available for applications where direct immersion 
of the sensing bulb is desired. A 124904 Well Adapter 
(see Fig. 2) can be ordered separately to adapt some 
other wells to the mounting clamp. The boiler must be 
provided with a tapping that allows horizontal mounting of 
the well. It should be located where boiler water of 
average temperature can circulate around the well.

1. Turn off all power and drain the boiler.
2. If no tapping is provided, prepare one, properly 

sized and threaded, at the selected location.

3. Install the immersion well in the boiler tapping and 

tighten securely.

NOTE: Do not use the case as a handle to tighten.

4. Refill boiler and check for water leakage.
5. Loosen but do not remove the clamp screw on 

the bottom (L8124A,E) or on top (L8124C,L,M) 
of case.

6. Insert the element in the well until it bottoms. 

See Fig. 2.

7. Fit the case onto the well so that the clamp on the 

case slides over the flange on the well. Securely 
tighten clamp screw. 

Electrical Shock Hazard.
Can cause severe injury, death or equipment 
damage.
Disconnect power before wiring to prevent 
electrical shock or equipment damage.

All wiring must comply with local electrical codes and 
ordinances. The limits given in the Specifications section 
must not be exceeded when applying this control. 
Terminals on these Aquastat Relays are approved for 
copper wire only.

Refer to the insert on the inside of the Aquastat Relay 
cover or to Table 1 for electrical ratings and maximum 
load information. Use manufacturer instructions when 
wiring controlled equipment or refer to typical hookups in 
Fig. 3 through 11.

Explosion Hazard.
Can cause severe injury, death or property 
damage.
Use this product only in systems with a pressure 
relief valve.

If the B1 terminal on the device being replaced is a 1/4 in. 
(6 mm) tab terminal, use the existing wiring harness 
terminals to install the replacement device. If the B1 
terminal on the device being replaced is a screw 
terminal, insert the provided tab terminal to screw 
terminal adapter on the 1/4 in. (6 mm) tab terminal of the 
replacement device. After the adapter is installed, the 
existing wraparound wire end may be reused to make an 
electrical connection to the B1 terminal.

M8882

SENSING ELEMENT IS FACTORY FORMED FOR 1.5 IN.
INSULATION WELL ASSEMBLIES.

FOR 3 IN. INSULATION WELL ASSEMBLIES, PULL OUT
SUFFICIENT CAPILLARY TO ASSURE THAT THE CAPSULE
BOTTOMS IN THE WELL.

STRAIGHTEN CAPILLARY  SUFFICIENTLY SO IT DOES NOT 
INTERFERE WITH INSERTION OF THE CAPSULE INTO THE WELL.

CAUTION:
EXCESSIVE HANDLING OR SHARP BENDS 
CAN DAMAGE THE CAPILLARY.

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