Taco, Inc. will repair or replace without charge
(at the company’s option) any product or part
which is proven defective under normal use with-
in three (3) years from the date of start-up or
three (3) years and six (6) months from date of
shipment (whichever occurs first).
In order to obtain service under this warranty, it
is the responsibility of the purchaser to promptly
notify the local Taco stocking distributor or Taco
in writing and promptly deliver the subject prod-
uct or part, delivery prepaid, to the stocking dis-
tributor. For assistance on warranty returns, the
purchaser may either contact the local Taco
stocking distributor or Taco. If the subject prod-
uct or part contains no defect as covered in this
warranty, the purchaser will be billed for parts
and labor charges in effect at time of factory
examination and repair.
Any Taco product or part not installed or operat-
ed in conformity with Taco instructions or which
has been subject to misuse, misapplication, the
addition of petroleum-based fluids or certain
chemical additives to the systems, or other
abuse, will not be covered by this warranty.
If in doubt as to whether a particular substance
is suitable for use with a Taco product or part, or
for any application restrictions, consult the
applicable Taco instruction sheets or contact
Taco at [401-942-8000].
Taco reserves the right to provide replacement
products and parts which are substantially simi-
lar in design and functionally equivalent to the
defective product or part. Taco reserves the right
to make changes in details of design, construc-
tion, or arrangement of materials of its products
without notification.
TACO OFFERS THIS WARRANTY IN LIEU OF
ALL OTHER EXPRESS WARRANTIES. ANY
WARRANTY IMPLIED BY LAW INCLUDING
WARRANTIES OF MERCHANTABILITY OR
FITNESS IS IN EFFECT ONLY FOR THE
DURATION OF THE EXPRESS WARRANTY
SET FORTH IN THE FIRST PARAGRAPH
ABOVE.
THE ABOVE WARRANTIES ARE IN LIEU OF
ALL OTHER WARRANTIES, EXPRESS OR
STATUTORY, OR ANY OTHER WARRANTY
OBLIGATION ON THE PART OF TACO.
TACO WILL NOT BE LIABLE FOR ANY SPE-
CIAL, INCIDENTAL, INDIRECT OR CONSE-
QUENTIAL DAMAGES RESULTING FROM
THE USE OF ITS PRODUCTS OR ANY INCI-
DENTAL COSTS OF REMOVING OR REPLAC-
ING DEFECTIVE PRODUCTS.
This warranty gives the purchaser specific rights,
and the purchaser may have other rights which
vary from state to state. Some states do not
allow limitations on how long an implied warranty
lasts or on the exclusion of incidental or conse-
quential damages, so these limitations or exclu-
sions may not apply to you.
LIMITED WARRANTY STATEMENT
ond sensor can be placed alongside the one to be tested and the read-
ings compared. First measure the temperature using the thermometer
and then measure the resistance of the sensor at the control. The wires
from the sensor must not be connected to the control while the test is
performed. Using the chart below, estimate the temperature measured
by the sensor. The sensor and thermometer readings should be close.
If the test meter reads a very high resistance, there may be a broken
wire, a poor wiring connection or a defective sensor. If the resistance is
very low, the wiring may be shorted, there may be moisture in the sen-
sor or the sensor may be defective. To test for a defective sensor, mea-
sure the resistance directly at the sensor location.
The installer must ensure that this control and its wiring are isolated
and/or shielded from strong sources of electromagnetic noise. This
device complies with part 15 of the FCC Rules. Operation is subject to
the following two conditions: (1) This device may not cause harmful inter-
ference, and (2) this device must accept any interference received, includ-
ing interference that may cause undesired operation.
TECHNICAL DATA:
SR501-OR Boiler Reset Control Relay:
Control:
Microprocessor PI control.
This is not a
safety (limit) control.
Enclosure:
TYPE 1
Dimensions:
4
1
⁄
4
" W x 5
1
⁄
4
" H x 2
3
⁄
4
" D
Approvals:
UL listed for US and Canada, Temperature
Indicating and Regulating Equipment.
Power Supply:
120/60/1 VAC, 12 amps maximum
Relays: Boiler Relay 1 amp @ 24 VAC
Circulator Relay
1
⁄
3
HP (6 FLA, 36
LRA)
Thermostat: 24 VAC Class 2 Output
Sensors: NTC thermistor, 10 k
Ω
@ 77°F
(25°C ±0.2°C) ß=3892
Outdoor Design Temp.: -30°F to 40°F (-35°C to 5°C)
Boiler Minimum: 70°F or 140°F (21°C or 60°C)
Differential: 10°F or 20°F (6°C or 12°C)
WWSD: 70°F (21°C), blinks TSTAT light when
>70°F
WARNING:
Wiring connections must be made in accordance with all applicable electrical codes. Use copper wire only. 120 VAC wiring must have a min-
imum temperature rating of 75°C. Failure to follow this instruction can result in personal injury or death and/or property damage. 12-18 gauge wire rec-
ommended for 120 VAC connections, 14-22 gauge wire for thermostat connections, and 14-22 gauge wire for 24 VAC source connections.
TEMPERATURE RESISTANCE
°F
°C
Ω
-30
-34
234,196
-20
-29
165,180
-10
-23
118,018
0
-18
85,362
10
-12
62,465
20
-7
46,218
TEMPERATURE RESISTANCE
°F
°C
Ω
30
-1
34,558
40
4
26,099
50
10
19,900
60
16
15,311
70
21
11,883
80
27
9,299
TEMPERATURE RESISTANCE
°F
°C
Ω
90
32
7,334
100
38
5,828
110
43
4,665
120
49
3,760
130
54
3,050
140
60
2,490
TEMPERATURE RESISTANCE
°F
°C
Ω
150
66
2,045
160
71
1,689
170
77
1,403
180
82
1,172
190
88
983
200
93
829
Optional power stealing thermostat resistor part number: SRTR-001RP
(Value: 1000 Ohms, 1/2 watt or higher)
Replacement Switching Relay fuses part number: SR6A-001RP
(Manufacture: Littlefuse, Part Number: 229006)
A Taco Family Company
2016
