Honeywell L8124a C Manual

® U.S. Registered Trademark
Copyright © 2001 Honeywell  •  All Rights Reserved 
INSTALLATION INSTRUCTIONS
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L8124B,E,G,L
Aquastat
® Relays
APPLICATION
These immersion type controllers provide high limit, low 
limit, and circulator control in forced hydronic heating 
systems that include domestic hot water. Table 1 lists the 
various TRADELINE
® models and applications.
SPECIFICATIONS
Low Limit:
Setting: 110°F to 220°F (43°C to 104°C), adjustable.
Differential: 10°F to 25°F (6°C to 14°C),...

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.
Fig. 1. Internal view of L8124G,L.
WARNINGExplosion Hazard.
Can cause serious injury, death or property 
damage.
Use this product only in systems with a pressure 
relief valve.
WARNINGElectrical Shock Hazard.
Can cause serious injury or death.
Disconnect power supply before beginning 
installation to prevent electrical shock or 
equipment damage.
IMPORTANT:
1. Terminals on these Aquastat
® Relays are 
approved for copper wire only.
2. Immersion well must snugly...

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5.5.If the old immersion well is otherwise suitable but 
does not fit the L8124 Clamp, the124904 Well 
Adapter (ordered separately) must be used as 
follows:a. After loosening the immersion well clamp 
screw, fit the adapter onto the capillary tube 
(Fig. 3).
b. Make sure the adapter fits into the hole in the 
case. Position the clamp properly on the 
adapter flange, then tighten the clamp screw.
c. Return to step 4a. above, and complete the 
installation.
Fig....

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Fig. 4. L8124B in gas-fired, millivolt, forced hot water, tankless, zoned pump system.
Fig. 5. L8124B single zone connections and internal 
schematic.Fig. 6. L8124Esingle zone connections and internal 
schematic.
L1 (HOT)
L2
1
2
3
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED.
CONTROL CASE MUST BE CONNECTED TO EARTH GROUND. USE GROUNDING SCREW PROVIDED.
B1 IS 1/4 IN. TAB TERMINAL.
TT
1
23
456
M8841
THPP
1
2
3TRPP
MILLIVOLTAGE
GAS...

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Fig. 7. L8124E in 24V, gas-fired, forced hot water, tankless, zoned, pump system.
Fig. 8. L8124E in 24V, gas-fired forced hot water, 
tankless system.
Fig. 9. L8124G,L multizone system with zone valve 
connections and internal schematic.
L1 (HOT)
L2
1
2
3
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED.
CONTROL CASE MUST BE CONNECTED TO EARTH GROUND. USE GROUNDING SCREW PROVIDED.
B1 IS 1/4 IN. TAB TERMINAL.
TT
1
23
456
M1794A
TH...

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Fig. 10. L8124E multizone system with circulator connections and internal schematic.
Fig. 11. L8124L multizone system with circulator connections and internal schematic.
M8828
L1 
(HOT) L21
1
2
3POWER SUPPLY. PROVIDE DISCONNECT MEANS AND 
OVERLOAD PROTECTION AS REQUIRED.
CONTROL CASE MUST BE CONNECTED TO EARTH 
GROUND. USE GROUNDING SCREW PROVIDED.
B1 IS 1/4 IN. TAB TERMINAL.
2
1
4
3
5
6
ZONE 1
LOW VOLTAGETHERMOSTAT R845A RELAY ZONE 1
ZONE 1
CIRCULATOR TO...

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Fig. 12. Relationship of setpoints and 
differential adjustments.
Fig. 13. Setting stop in position to limit the high limit 
setting to 180°F (82°C).
OPERATION (FIG. 12)
High LimitThe high limit opens and turns off the burner when the 
water temperature reaches the set point. The high limit 
automatically resets after the water temperature drops 
past the set point and through the 10°F (6°C) differential.
WARNINGExplosion Hazard.
Can cause serious injury, death...

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MATERIAL SAFETY DATA SHEET
Section 1. Product And Company 
Identification
Product Name: Heat Conductive Compound
MSDS ID: DS9021
Synonyms: MS1699
Product Use: Heat conductive material used to enhance 
contact and heat transfer in temperature sensor 
applications.
Manufacturer: Honeywell Inc., 1985 Douglas Drive North, 
Minneapolis, MN 55422.Date Released: October 8, 1999
Customer Response Center: 800-328-5111
Emergency Telephone Information: 888-809-3787
NFPA...

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Section 7. Handling and StorageStore in dry place. Keep container closed when not in 
use.
Section 8. Exposure Controls and 
Personal Protection.
Ventilation: No special ventilation is required when 
working with this product.
Respiratory Protection: None required.
Eye Protection: Not normally required. However, use 
chemical safety goggles or faceshield if potential for 
eye contact exists, especially if material is heated.
Hand/Clothing Protection: Not normally...

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