resideo Aquastat L8148A User manual

PRODUCT DATA
60-2278-10
L8148A,E,J
Aquastat® Relays
APPLICATION
The L8148 Aquastat®Relays are immersion type hydronic
controllers that combine high limit protection with switching
relay control of burner and circulator motors.
FEATURES
• All models are used with a 24 Vac thermostat.
• Models include special terminals for adding remote, low
limit temperature control.
• L8148E,J have terminals for adding zone valve system
wiring.
• L8148E models are available with plug for connecting
Aquastat Relay directly to D892/M892 Vent Dampers.
• All devices include transformer to provide power for the
low voltage control circuit. Different models provide
switching of line, low, or millivoltage burner circuit.
• Case available for horizontal or vertical mounting.
• Combinations of two insulation and two insertion well
lengths are available.
Horizontal
Mounting
Vertical
Mounting
Contents
Application .......................................................................... 1
Features .............................................................................. 1
Specifications ..................................................................... 2
Installation .......................................................................... 3
Setting and Adjustments ................................................... 11
Operation ............................................................................ 11
Checkout ............................................................................. 11

L8148A,E,J AQUASTAT® RELAYS
60-2278—10 2
SPECIFICATIONS
IMPORTANT
The specifications given in this publication do not
include normal manufacturing tolerances. Therefore,
this unit may not exactly match the listed
specifications. Also, this product is tested and
calibrated under closely controlled conditions, and
some minor differences in performance can be
expected if those conditions are changed.
Models: See Table 2.
Electrical Ratings:
Table 1. Circulator Control Circuit (Amperes).
Voltage and Frequency: 120 Vac, 60 Hz.
Burner Control Circuits:
Line Voltage: Ratings same as for circulator above.
Low Voltage: 0.8A maximum at 24 Vac.
Millivoltage: 0.25A at 1/4 to 12 Vdc.
Approvals:
Underwriters Laboratories Inc. Listed: File No. MP466, Guide
No. MBPR (models with well); Guide No. MBPR2 (models
without well).
Canadian Standards Association Certified: File No. LR1620,
Guide No. 400-E-O.
ANSI Miswiring: Models with 1/4 in. tab terminal meet ANSI
Appliance Miswiring Standard.
Immersion Well Dimensions:
Brass Spud for Boiler Fitting: 1/2 or 3/4 NPT.
Insulation Depth: 1-1/2 or 3 in. (38 or 76 mm).
NOTE: Not all models include wells. If well is not included
but is needed, refer to form 68-0040 to order.
Insertion Length: 3-3/8 in. (86 mm).
Maximum Pressure On Immersion Well:
255 psi (1758 kPa).
Maximum Bulb Temperature:
40°F higher than setpoint, or up to 265°F (23°C higher than
setpoint, or up to 129°C).
Material Safety Data Sheets (MSDS): For more information on
heat-conductive compound, see form 69-0955.
Maximum Ambient Temperature:
150°F (66°C) with 1.2A, 24V load.
77°F (25°C) with 1.4A, 24V load.
Table 2. Standard L8148 Model Specifications.
aSee Fig. 1 for case dimensions.
bNumber of V8043 Zone Valves that can be powered from the L8148 without additional transformer(s). 1.2A load is the
maximum permissible when ambient temperature exceeds 77°F (25°C).
cNumber of R8230C Relays that can be powered from the L8148. Additional relays in groups of four or fewer require an additional
transformer.
dModels available with plug for connecting L8148E directly to the D892/M892 Vent Dampers.
eModels available with plug (L8148E) and 50 VA transformer are for use with the Resideo SV9500/SV9600 SmartValve® System
Control. No zone valves or relays can be powered from the L8148 when used with SV9500/SV9600 gas valves.
Maximum Ambient Temperature:
150°F (66°C) with 1.2A 24V load;
77°F (25°C) with 1.4A 24V load.
Thermostat Heat Anticipator Setting: 0.2A.
Standard Scale Range: 180°F to 240°F (82°C to 116°C).
Differential: Nonadjustable.
Finish: Gray enamel.
Optional Specifications:
Scale Range: 140°F to 240°F (60°C to 116°C).
High Limit Dial Stop.
Case Dimensions: See Fig. 1.
Accessories:
107408 Heat Conductive Compound (4 oz. can). For
more information, see form 69-0955, Heat Conductive
Compound.
124904 Well Adapter. For ordering information, see form
68-0040, Immersion Wells and Compression Fittings.
Type 120 Vac 240 Vac
Full Load 7.4 3.7
Locked Rotor 44.4 22.7
Model
Number
Burner
Circuit
Voltage
Mounting
Casea
Special
Provision for
Adding Remote
Low Limit
High
Limit
Second
Limit
Circulator
Control
Maximum Number
of Zone Controls
Thermostat
Required
Manual/
Auto
SwitchValvesbRelaysc
L8148A Line Horizontal Yes Yes No Can be
added
remotely
— — 24V No
L8148Ed,e Low Vertical 2 4
L8148J Low or
millivolt
Vertical or
horizontal
Yes

L8148A,E,J AQUASTAT® RELAYS
360-2278—10
Fig. 1. L8148 dimensions in in. (mm).
Fig. 2. Internal view of L8148A Aquasta® Relay.
Fig. 3. Internal view of L8148E Aquastat® Relay.
INSTALLATION
When Installing this Product…
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.
WARNING
Explosion Hazard.
Can cause severe injury, death or property damage.
This product is intended for use only in systems with a
pressure relief valve.
WARNING
Electrical Shock Hazard.
Can cause severe injury, death or equipment damage.
1. Disconnect power supply before beginning
installation to prevent electrical shock or equipment
damage.
2. Never apply a jumper across (or short) terminals B1,
B2, or B3. This burns out the transformer.
3-1/8
(79)
1/8 (3)
6-1/8
(156)
3-3/8
(86)
2-1/8 (54)
(VERTICAL
MOUNT)
1-1/4 (32) (HORIZONTAL
MOUNTÑBOTTOM)
KNOCKOUTS FOR
1/2 (13) CONDUIT
4-5/16 (110)
1-1/4 (32)
(VERTICAL
MOUNT)
3-1/16 (78)
(HORIZONTAL
MOUNT)
M8925
M8926
VOLTAGE
BARRIER
TRANSFORMER
SWITCHING
RELAY
HIGH
LIMIT
DIAL
M8927
TRANSFORMER
SWITCHING
RELAY
HIGH
LIMIT
DIAL
GROUNDING SCREW

L8148A,E,J AQUASTAT® RELAYS
60-2278—10 4
Mounting
Boilers have tappings to allow immersion well (which must be
ordered separately) to be mounted horizontally so boiler water
of average temperature can circulate freely around the well.
1. Turn off all power and drain the boiler.
2. If no tapping is provided, prepare one properly sized and
threaded, and locate near the top of the boiler.
3. Coat the well threads sparingly with pipe dope, install
the well in the boiler tapping, and tighten securely.
NOTE: Do not attempt to tighten by using the case as
a handle.
4. Refill the boiler and check for water leakage.
5. Increase sensitivity of the bulb by coating with a good
heat-conductive compound. When used, coat the bulb
completely.
6. Insert the bulb element into the well until it bottoms. If
necessary, slightly bend the tube inside the case to hold
the bulb against the bottom of the well.
NOTE: Some models have a tubing length adjustable to 3 in.
(76 mm). In these models, pull out extra tubing from
inside the case, if needed.
7. Center the loop of excess tubing in front of the
immersion well so it cannot touch any electrical parts.
8. Fit the case onto the well so the clamp on the case
slides over the flange on the well. Tighten the clamp
screw securely.
IMPORTANT
Best thermal response is obtained with a well that
snugly fits the sensing bulb. For wells used, the bulb
should be inserted until it rests against the bottom of
the well. Use a well of correct length and bend the
tubing, if necessary, to hold the bulb against the
bottom of well, but do not make a sharp bend in the
tubing.
If the well does not fit snugly on the bulb, use the heat-
conductive compound as follows: Fold the plastic bag of
compound lengthwise and twist it gently. Then snip off the
end of the bag and work the open end of the bag all the way
into the well. Slowly pull out the bag while squeezing it firmly
to distribute the compound evenly in the well. Insert the bulb
all the way to the bottom of the well. Bend the tubing, if
necessary, to hold the bulb against the bottom of the well and
to hold the outer end of the bulb firmly in contact with the side
of the well (Fig. 4). Wipe excess compound off the outer end of
the well.
Wiring
IMPORTANT
Terminals on the L8148 Aquastat Relay are approved
for use with only copper wire. The terminals allow
only wrap-around wiring.
1.Strip 7/16 in. of insulation
from the wire end.
2.Wrap the wire at least 3/4 of
the distance around the screw
as shown.
3.Using a standard, flat-headed
screwdriver, tighten the screw
until the wire is snugly in
contact with the screw and contact plate.
4. Tighten the screw an additional one-half turn.
NOTE: Do not use a push-type ratchet screwdriver.
Disconnect power supply before making wiring connections
to prevent electrical shock or equipment damage.
All wiring must comply with local electrical codes and
ordinances. Do not exceed limits in the Specifications section
when applying this control.
When wiring a switch equipped with 1/4 in. tab terminal
connector, use 18 to 22 gauge wire with AMP Inc. part no.
2-520129-2 fully insulated flag receptacle connector or
equivalent.
The L8148E,J can power up to two V8043 Zone Valves.
Additional valves, in groups of two or fewer, require an
additional transformer. Follow appropriate wiring diagrams,
see Fig. 5 through 14, when using zone valves or a low limit
controller.
NOTE: On systems requiring a vent damper, the vent damper
can be connected directly to some L8148E Aquastat
Relay models (Fig. 12) or an S8610 Ignition Module
(Fig. 11).
When the vent damper is plugged into the Aquastat Relay, a
fuse in the Aquastat Relay will blow when the thermostat first
closes. Once the fuse is blown, the Aquastat Relay will not
operate unless the vent damper is connected.
When the vent damper is plugged into the Aquastat Relay, a
fuse in the Aquastat Relay will blow when the thermostat first
closes. Once the fuse is blown, the Aquastat Relay will not
operate unless the vent damper is connected.
With the vent damper plugged into the S8610, a fuse in the
ignition module will blow when first powered. Once the fuse is
blown, the ignition module will not operate unless the vent
damper is connected.
M8843A

L8148A,E,J AQUASTAT® RELAYS
560-2278—10
Fig. 4. Position of bulb in immersion well, and use of well adapter when required.
CAUTION
Equipment Damage Hazard.
Exceeding load limits can damage the equipment.
1. When L8148E or J is used to power zone valves, low voltage 1.4A; 1.2A load is the maximum permissible when ambient
temperature exceeds 77°F (25°C). Use additional transformer(s) if load exceeds ratings.
2. When L8148E (with 50 VA transformer) is used to power SV9500/SV9600, a separate transformer must be used to
power zone valves.
Fig. 5. External connections and internal schematic for L8148A.
CONTROLLER
CASE
IMMERSION
WELL CLAMP
ADAPTER
IMMERSION
WELL SPUD
BOILER
OLD IMMERSION
WELL ASSEMBLY
BACK OF
CONTROLLER
CASE
IMMERSION
WELL CLAMP
SCREW
ADAPTER
SENSING
BULB
HEAT-CONDUCTIVE COMPOUND
SETSCREW
CAPILLARY
TUBE
(C)
IMMERSION
WELL CLAMP
IMMERSION
WELL CLAMP SCREW
SHORT TUBE
FITS IN CENTRAL
RECESS OF ADAPTER
BEND THE CAPILLARY TUBE TO HOLD THE SENSING BULB IN GOOD
THERMAL CONTACT WITH THE IMMERSION WELL AT POINTS (A) AND (B).
ASSURE THAT CAPILLARY TUBE FITS FREELY IN THE ADAPTER SO THE
TENSION OF THE CAPILLARY TUBE AT POINT (C) HOLDS THE SENSING
BULB IN GOOD THERMAL CONTACT WITH THE IMMERSION WELL AT POINT (D).
M8830A
1
1
2
2
(D)
(B)
(A)
C1 C2 B1 B2
R
W
B
GL1 L2 TT
3
B
R
L1
L2
G
TT3
C1
C2 B2 B1
JUMPER
1K 1K2
1K1
BR
L6006
LOW LIMIT
CONTROLLER
L1
HOT
L2
24V
THERMOSTAT
L8148A
HIGH
LIMIT
TO LINE
VOLTAGE
OIL BURNER
RELAY OR
GAS VALVE
CIRCULATOR
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD
PROTECTION AS REQUIRED.
REMOVE JUMPER WHEN ADDING L6006 LOW LIMIT CONTROLLER.
CONTROL CASE MUST BE CONNECTED TO EARTH GROUND.
USE GROUNDING SCREW PROVIDED.
B1 IS 1/4 IN. TAB TERMINAL.
1
2
3
4
4
1
2
3
M2842A
L8148A 4