The Zone Valve Control 304V connects up to four thermostats and operates zone valves to provide heating to a zoned
hydronic heating system. The 304V operates a system pump whenever a zone valve opens. Zone 1 can operate either
a zone valve or a circulator to provide heat to an indirect domestic hot water tank with optional priority over zones
2 through 4. The 304V includes optional exercising to prevent circulator seizure when not in use, and optional post
purge operation of the domestic hot water tank to maximize energy savings. The 304V provides a RoomResponse
signal to modulating-condensing boilers to optimize comfort while improving boiler efficiency.
Features
• RoomResponse
• Compatible with all 24 V (ac) thermostats
• Compatible with 2, 3 and 4-wire zone valves
• Unlimited zone expansion
• Zone priority
• Priority override
• Pump exercising
• Post purge
TM
signal
•
LED for each zone, priority, end switch and RoomResponse
User Interface ....................................................................7
Indicator LED ................................................................. 7
Sequence of Operation .....................................................7
Technical Data ...................................................................8
Limited Warranty and Product Return Procedure .............8
Important Safety Information
It is your responsibility to ensure that this control is safely installed according to all applicable codes and standards. tekmar is
not responsible for damages resulting from improper installation and/or maintenance.
This is a safety-alert symbol. The safety alert symbol is shown alone or used with a signal word (DANGER,
WARNING, or CAUTION), a pictorial and/or a safety message to identify hazards. When you see this symbol
alone or with a signal word on your equipment or in this manual, be alert to the potential for death or serious
personal injury.
This pictorial alerts you to electricity, electrocution, and shock hazards.
This symbol identifies hazards which, if not avoided, could result in death or serious injury.
This symbol identifies hazards which, if not avoided, could result in minor or moderate injury.
This symbol identifies practices, actions, or failure to act which could result in property damage or damage to
the equipment.
Read manual and all product labels BEFORE using the equipment. Do not use unless you know
the safe and proper operation of this equipment. Keep this manual available for easy access by all
users. Replacement manuals are available at tekmarControls.com
•
It is the installer’s responsibility to ensure that this control is safely installed according to all applicable codes and
standards.
•
Improper installation and operation of this control could result in damage to the equipment and possibly even personal
injury or death.
• This control is not intended for use as a primary limit control. Other controls that are intended and certified as safety limits
must be placed into the control circuit.
The control includes fuses and transformer that are serviceable. Do not attempt to service any other parts on the control.
Attempting to service the control voids the warranty.
• Strip all wiring to a length of 3/8 in. or 10 mm for all terminals.
• A circuit breaker or power disconnect that provides power to the control should be located nearby and clearly labeled.
• Refer to the current and voltage ratings at the back of this manual before connecting devices to this control.
The installer must ensure that this control and its wiring are
isolated and/or shielded from strong sources of electromagnetic
noise. Conversely, this Class B digital apparatus complies
with Part 15 of the FCC Rules and meets all requirements of
the Canadian Interference-Causing Equipment Regulations.
However, if this control does cause harmful interference to
radio or television reception, which is determined by turning
the control off and on, the user is encouraged to try to correct
the interference by re-orientating or relocating the receiving
antenna, relocating the receiver with respect to this control,
and/or connecting the control to a different circuit from that
to which the receiver is connected.
Cet appareil numérique de la classe B respecte toutes les exigences du Règlement sur le matériel brouilleur du Canada.
• Needle-nose pliers
• Wire stripper
• Four 1/8" - 1" wood screws
• 1 Installation and Operation Manual 304V_D
Location
• Keep the control dry. Avoid potential leakage onto the control.
• Maintain relative humidity less than 90% in a non-condensing environment.
• Avoid exposure to extreme temperatures beyond 32-122°F (0-50°C).
• Install away from equipment, appliances, or other sources of electrical interference.
• Install to allow easy access for wiring, viewing, and adjusting the display screen.
• Install approximately 5 feet (1.5 m) off the finished floor.
• Locate the control near pumps and/or zone valves if possible.
• Provide a solid backing which the enclosure can be mounted to. Example: plywood or wall studs.
• Use the conduit knockouts provided on the upper, lower, and back of the enclosure for wiring.
Installing the Enclosure
To prevent the risk of personal injury and/or death, make sure power
is not applied to the control until it is fully installed and ready for final
testing. All work must be done with power to the circuit being worked
on turned off.
Please be aware local codes may require this control to be installed
or connected by an electrician.
The Zone Valve Control 304V operates four heating zones. When the thermostat calls for heat, the zone valve opens, the system
pump is turned on and the boiler is fired.
Master
T-stat 1 Priority = Off
Exercising = On
Post Purge = On
Mod Boiler = depends on boiler
System Pump During Priority = On
System Pump With Member Calls = Off
Zone Valve End Switches = Off
Included 510 Ω resistor must
be installed when using power
stealing thermostats
(e.g. Thermostat T3)
The Zone Valve Control 304V operates a three heating zones and a domestic hot water tank. When a thermostat calls for heat,
the zone valve opens and the system pump and the boiler turn on once the zone valve end switch closes. The domestic hot
water tank is heated using a pump. When priority is selected, the heating zones are shut off while the hot water tank is heated.
End switch jumper required for Zone 1
when using a pump and Zone Valve End
Switch DIP = On
T1
T2T3
A1
P1L NPS
V1
V2V3
5 of 12
DIP Switches
Master
T-stat 1 Priority = On
Exercising = On
Post Purge = On
Mod Boiler = depends on boiler
System Pump During Priority = Off
System Pump With Member Calls = On
Zone Valve End Switches = On
Included 510 Ω resistor must
be installed when using
power stealing thermostats
(e.g. Thermostat T3)
Two Zone Valve Control 304V operate seven heating zones and a domestic hot water tank. When a thermostat calls for heat,
the zone valve opens. The hot water tank is heated using a pump when the tank aquastat calls for heat. The master control
operates the system pump and the boiler when there is a call for heat on either the master or member control.
Off when power disconnected or transformer fuse is blown.
Priority
• On when zone 1 has priority over zones 2 to 4.
• Flashing while in priority override.
RoomResponse
• On when modulating condensing boiler is operating below
maximum setting.
TM
System Pump
• On when zone valve end switches are closed (valve open).
•
Off when zone valve end switches are open circuit (valves closed).
Sequence of Operation
Zone Operation
When a thermostat calls for heat by closing the R and W terminals:
• 24 V (ac) is applied to the corresponding zone valve.
• The corresponding zone indicator LED is turned on.
Boiler Operation
When a thermostat calls for heat by closing the R and W terminals:
• The boiler end switch XX is closed to fire the boiler. This re-
quires the control DIP switch to be set to Master.
• The RoomResponseTM 0-10 V (dc) or 4-20 mA signal is sent
to a modulating-condensing boiler.
DHW Operation
Many modulating-condensing boilers have multiple temperature
call inputs. Wire the DHW end switch to input recommended
in the boiler's manual.
When a zone 1 calls for heat by closing the R and W terminals:
• The DHW end switch is closed to fire the boiler at the DHW
temperature.
• The Mod Boiler output is changed to 10 V (dc) or 20 mA.
Priority Override
•
The Priorit y LED light flashes when priority override is in effect.
•
Priority for zone 1 is in effect for 60 minutes after which priority
override starts by shutting off zone 1 and resumes heating
on zones 2 through 4 and expansion zones.
•
During priority override, the mod max dial setting limits the
RoomResponseTM Signal to the boiler.
Master / Member DIP Switch
•
Allows for unlimited expansion using additional Switching
Relays and/or Zone Valve Controls.
•
The Master Switching Relay is wired and operates the boiler.
• If using a single Switching Relay set to Master.
•
When using multiple Switching Relays and/or Zone Valve
Controls, set one control to Master and set all other controls
to Member.
•
The boiler end switch XX only closes when the DIP switch
is set to Master and does not close when set to Member.
T-Stat 1 Priority DIP Switch
When T-Stat 1 is calling for heat by closing the R and W terminals:
• 115 V (ac) is applied to the Priority Pump 1.
• Zone 1 indicator LED is turned on.
• Priority indicator LED is turned on.
• Zones 2 to 4 zone valves and LEDs are turned off.
• Expansion Member controls shut off their zones.
Zone 1 Call
• On when thermostat 1 calls for heat.
• Off when thermostat 1 stops calling for heat.
Zones 2 to 4 Call
• On when the corresponding thermostat calls for heat.
• Off during priority operation.
• Off when corresponding thermostat stops calling for heat.
Zones 1 to 4 Valve Open
•
On when corresponding thermostat calls for heat and the
zone valve is open (zone valve end switch closed).
•
Off when zone valve closed (zone valve end switch open circuit).
• Off when corresponding thermostat stops calling for heat.
• After 60 minutes of continuous zone 1 call for DHW heating
the control goes into priority override. This prevents building
freeze up if the DHW tank aquastat fails in the closed position.
• A jumper wire must be installed on the zone 1 end switch if
a pump is installed and the Zone Valve End Switches DIP
switch is set on.
Exercising DIP Switch
ON: Each circulator pump is energized for 30 seconds every
72 hours.
OFF: Circulator pump exercising disabled.
Post Purge DIP Switch
ON: After thermostat 1 stops calling for heat, the zone 1 priority
pump and zone valve remain on for 2 minutes to purge heat
from the boiler to the zone.
OFF: Post purge disabled.
Mod Boiler DIP Switch
Select either 0-10 V (dc) or 4-20 mA signal to the modulating
condensing boiler. Consult the boiler manual to determine the
signal type. The DIP switch position does not matter if the
modulating boiler output is not used.
System Pump During Priority DIP Switch
On: System pump operates when zone 1 calls for heat.
Off: System pump shuts off when zone 1 calls for heat. Typically
set off when using a pump for heating a domestic hot water tank.
System Pump With Member Call DIP Switch
On: System pump on the master control runs when a zone on
a member control calls for heat.
Off: System pump on the master control does not turn on when
a zone on a member control calls for heat.
Zone Valve End Switches DIP Switch
On: System pump and boiler will not turn on until the zone
valve end switch is closed. Select this option when using 3 or
4-wire zone valves.
Off: System pump and boiler turn on immediately when a
thermostat calls for heat. Select this option when using 2-wire
zone valves.
Fuses
• All fuses are T5A 250V slow blow.
•
Fuse 1 and 2 correspond to the 24 V (ac) transformer power
supply. If a fuse is blown, first check that the thermostat wiring
is not shorted. Then replace the fuse.
The RoomResponseTM signal adjusts the temperature of a
modulating condensing boiler that accepts a 0-10 V(dc) or 4-20
mA signal input. It works by continually adjusting boiler water
temperatures to the lowest possible value to meet comfort
without wasting energy. This is done by monitoring each
thermostat's on and off time pattern and determines the ideal
water temperature for each zone. The control then chooses the
highest water temperature requirement of all the thermostats
and provides a 0-10 V (dc) or 4-20 mA signal proportional to
the boiler operating temperature. The RoomResponseTM signal
is a DOE compliant method of controlling boiler temperature
to building load. The RoomResponseTM signal is not available
to on/off boilers.
Benefits of the RoomResponseTM signal include:
• Increase in boiler efficiency
• Reduction of room temperature swings
RoomResponseTM signal from member controls
Demand signal. 0 Vdc = demand. 2 Vdc = no demand
Mod Max % dial set to 100% in the illustration.
• Reduction in expansion noises from heating pipes
Mod Max % Dial
The upper limit of the 0-10 V (dc) or 4 -20 mA signal to the
modulating condensing boiler can be set using the Mod Max
% Dial. This sets the upper temperature limit for the boiler.
The dial is only applicable to controls set as the Master.
Mod Max %Max VoltageMax mA
50512
60613.6
70715.2
80816.8
90918.4
1001020
Setting the Max Mod % Dial
Required Adapter
Boiler Make/Model
Aerco AM seriesNot required0-10 V50%65%80%100 %
Bosch GreenstarICM Module0-10 V55%70%80%100%
Buderus GB142, GB162EM10 Module0-10 V50%60%75%90%
Burnham® Alpine
Camus® Modulating Micoflame
HTP EliteNot required0-10 V50%65%80%90%
IBC VFC and SL series*
Laars® Mascot LXNot required0-10 V55%70%85%100%
Laars® Mascot FTNot required0-10 V50%65%80%100 %
Lochinvar® Knight
Lochinvar
NTI Trinity Fire Tube and LXNot required4-20 mA55%65%75%90%
Literature304V_C, 304V_D, 304V_J
ControlMicroprocessor control. This is not a safety (limit) control.
Packaged weight5.0 lb. (2250 g)
Dimensions8-3/16" H x 10-11/16" W x 2-3/8" D (208 x 271 x 60 mm)
EnclosureCover: ABS plastic, Base: galvanized steel, NEMA type 1
Approvals
Ambient conditions32 to 122°F (0 to 50°C), ≤ 90% RH non-condensing
Power supply115 V (ac) ±10%, 60 Hz, 11 A
Transformer40 VA at 24 V (ac) , expandable to 80 VA with additional transformer M3069 (sold separately)
Control load7 VA at 24 V (ac)
FusesT5A 250 V slow blow 5 x 20 mm glass fuse, two spare fuses included
Zone valve outputs24 V (ac), 2 A max each, one transformer 33 VA, two transformer 73 VA
Zone valve end switch24 V (ac)
Pump relays230 V (ac), 5 A, 1/3 hp
Boiler XX end switch24 V (ac), 5 A
DHW end switch24 V (ac), 5 A
Mod boiler output0-10 V (dc) 500 Ω min impedance / 4-20 mA 1 kΩ max impedance
CSA C US, RoHS
Limited Warranty and Product Return Procedure
Limited Warranty The liability of tekmar under this warranty is limited. The
Purchaser, by taking receipt of any tekmar product (“Product”), acknowledges th e terms of the Limited Warranty in effe ct at the time of such Product
sale and acknowledges that it has read and understands same.
The tekmar Limited Warranty to the Purchaser on the Products sold hereunder
is a manufacturer’s pass-through warranty which the Purchaser is authorized to
pass through to its customers. Under the Limited Warranty, each tekmar Product is warranted against defects in workmanship and materials if the Product
is installed and used in compliance with tekmar’s instructions, ordinary wear
and tear excepted. The pass-through warranty period is for a period of twenty-four (24) months from the production date if the Product is not installed during
that period, or twelve (12) months from the documented date of installation if
installed within twenty-four (24) months from the production date.
The liability of tekmar under the Limited Warranty shall be limited to, at tekmar’s
sole discretion: the cost of parts and labor provided by tekmar to repair defects in
materials and / or workmanship of the defective product; or to the exchange of the
defective product for a warranty replacement product; or to the granting of credit
limited to the original cost of the defective product, and such repair, exchange or
credit shall be the sole remedy available from tekmar, and, without limiting the
foregoing in any way, tekmar is not responsible, in contract, tor t or strict product liability, for any other losses, costs, expenses, inconveniences, or damages,
whether direct, indirect, special, secondary, incidental or consequential, arising
from ownership or use of the produc t, or from defects in workmanship or materials,
including any liability for fundamental breach of contract.
The pass-through Limited Warranty applies only to those defective Products
returned to tekmar during the warranty period. This Limited Warranty does not
cover the cost of the parts or labor to remove or transport the defective Product, or
to reinstall the repaired or replacement Product, all such costs and expenses being
subjec t to Purchaser’s agreement and warrant y with its customers.
Any re pre sen tat ion s or war ranties about th e Produc ts made by Purchaser to its customers which are different from or in excess of the tekmar Limited Warranty are the
Purchaser’s sole responsibilit y and obligation. Purchaser shall indemnify and hold
tekmar harmless from and against any and all claims, liabilities and damages of any
kind or nature which arise out of or are related to any such representations or warranties by Purchaser to its customers.
The pass-through Limi ted Warrant y does not apply if the returned Produ ct has been
damaged by negligence by persons other than tekmar, accident, fire, Act of God,
abu se or misu se; or has been damaged by modi fications, alterations or att ach men ts
made subsequent to purchase which have not been authorized by tekmar; or if the
Product was not installed in compliance with tekmar’s instructions and / or the local
co des and ord inanc es; or if due to defe ctiv e ins ta llati on of the Produc t; or if the Pro duct was not used in compliance with tekmar’s instructions.
THIS WARRANTY IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESS OR
IMPLIED, WHICH THE GOVERNING LAW ALLOWS PARTIES TO CONTRACTUALLY EXCLUDE, INCLUDING, WITHOUT LIMITATION, IMPLIED WARRANTIES
OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, DURABILITY OR DESCRIPTION OF THE PRODUCT, ITS NON-INFRINGEMENT OF
ANY RELEVANT PATENTS OR TRADEMARKS, AND ITS COMPLIANCE WITH
OR NON-VIOLATION OF ANY APPLICABLE ENVIRONMENTAL, HEALTH OR
SAFETY LEGISLATION; THE TERM OF ANY OTHER WARRANTY NOT HEREBY
CONTRACTUALLY EXCLUDED IS LIMITED SUCH THAT IT SHALL NOT EXTEND
BEYOND TWENTY-FOUR (24) MONTHS FROM THE PRODUCTION DATE, TO
THE EXTENT THAT SUCH LIMITATION IS ALLOWED BY THE GOVERNING LAW.
Product Warranty Return Procedure All Products that are believed to have
defects in workmanship or materials must be returne d, together with a written
description of the defect, to the tekmar Representative assigned to the territory in
which such Product is located. If tekmar receives an inquiry from someone other
than a tekmar Representative, including an inquiry from Purchaser (if not a tekmar
Representative) or Purchaser’s customers, regarding a potential warranty claim,
tekmar’s sole obli gation shall be to pr ovide the address and other contact info rmation regarding the appropriate Representative.
WARNING: This product contains chemicals known to the State of
California to cause cancer and birth defects or other reproductive harm.
For more information: Watts.com/prop65
All specications are subject to change without notice