C
ONTROLS
M
ADE
E
ASY
.
®
TACO, INC.
, 1160 Cranston Street, Cranston, RI 02920 Telephone: (401) 942-8000 FAX: (401) 942-2360.
TACO (Canada), Ltd.
, 8450 Lawson Road, Unit #3, Milton, Ontario L9T 0J8. Telephone: 905/564-9422. FAX: 905/564-9436.
Visit our web site at:
http://www.taco-hvac.com
Printed in USA
Copyright 2013
TACO, Inc.
Taco, Inc. will repair or replace without charge
(at the company’s option) any product or part
which is proven defective under normal use
within 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 FIT-
NESS 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 STATU-
TORY, OR ANY OTHER WARRANTY OBLIGA-
TION 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 INCIDENTAL
COSTS OF REMOVING OR REPLACING
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 war-
ranty lasts or on the exclusion of incidental or
consequential damages, so these limitations or
exclusions may not apply to you.
LIMITED WARRANTY STATEMENT
120 VAC
INPUT
THERMOSTATS
BOILER
H
N
MASTER
EXISTING
ZONE
CONTROL
T
TO: "TT" ON BOILER
AQUASTAT
AQUASTAT ON
DHW HEATER
A
Note: If Zone Control comes on without a call for heat,
reverse Reset Override input (1 & 2) wires on SR501-EXP.
ZONE
CONTROL
BOIL
SEN
OUT
SEN
BOILER SENSOR
OUTDOOR
SENSOR
PC700
JUMPER
DHW
HEATER
CIRCULATOR
CIRCULATOR
PRIMARY
CIRCULATOR
(OPTIONAL)
POWER
ZONE 1
LED
INDICATORS
FUSE
6 AMP
FUSE
6 AMP
SR 501-EXP-4
POWER
CONTROLS
SLAVE
PRIORITY ON
RESET
PRIMARY PUMP ON
POST PURGE ON
PRIORITY PROTECT ON
PUMP EXERCISE ON
30 SEC/2 WK
MASTER
OFF
OFF
OFF
OFF
OFF
NORMAL
4 MIN/24 HOUR
ACCESSORY
PORT
H
N/O
N
H
120 VAC
CIRCULATOR
PRIMARY
OUTPUT
N/C
INPUT
120 VAC
END
SWITCH
RESET
OVERRIDE
THERMOSTAT
EXPANSION
X
W
R
X
1
A
2
C
B
24 VOLTS AC ONLY
C
SINGLE ZONE
EXPANDABLE SWITCHING RELAY
FOUR ZONE SWITCHING RELAY
120 VAC CIRCULATORS
ZC
INPUT
120 VAC
ZONE 1 ZONE 2 ZONE 3 ZONE 4
ZONE1 ZONE2 ZONE3
SR 504-4
FUSE
6 AMP
FUSE
6 AMP
FUSE
6 AMP
FUSE
6 AMP
FUSE
6 AMP
X X
R
W R
W R
W
R
W
ISOLATED
END
SWITCH THERMOSTATS (24 VAC)
PRIORITY
120 VAC
ZR
H
H
N H
N H
N H
N
H
N
H
ZONE4
ZONE 2
POWER
ZONE 1
ZONE 3
ZONE 4
LED
INDICATORS
ZONE 4
PRIORITY
OFF
ON
PRIORITY
SR501-EXP and PC700 Boiler Reset Control Connected to an Existing Switching Relay
For additional wiring diagrams, see www.taco-hvac.com.
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)
