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MANUALS (1)
Product Highlights
Description
The Taco SR506-5 Switching Relay is the best choice for all your zoning needs, with advanced PowerPort Cards, external diagnostic lights, switchable priority and contractor friendly PC board layouts. Combined with the time proven reliability of the 00 family of circulators and thermostats, total system integrating is achieved. External indicator lights provide instant diagnostic feedback, making a snap of service calls or new installation start-ups.
- Built-in; Post Purge and Pump Exercise Functions
- Switchable Primary Circulator Output
- Two Boiler Contacts, Utilizes Full Functionality of
- Mod-Con Boilers
- Expandable to 20 Zoning Panels (120 zones if all are six zone panels)
- Taco Control Mobile App (not Required for all functions)
- Wireless Update Capabilities
- Four Programmable Outputs
- DHW Recirculation Smartplus Logic
- Diagnostic Lights for All Outputs
- Additional Space for Wiring
- More Space To Write Zone Information
- Easy to Remove Hinged Cover
- Rear Knockouts
- Standard Control Upgradeable
Specs
| Depth (Inches): | 3" |
|---|---|
| Height: | 7-1/2" |
| Amperage: | 20 |
| Width (Inches): | 11-3/4" |
Questions?
Product Reviews
Most Liked Positive Review
Zones!
Most Liked Negative Review
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Fairly good. Could be better.
Broke down in the first season
I would not buy again
This zone controller is what i needed
Good product
Solid product.
Works great
Best product
6 Zone Relay for Circulator Pumps
I would buy this again
Great price and fast shipping.
Product Q&A
53 QuestionsQ: Can I use 4 Nest Thermostats with Taco SR504-4 ? Any special wiring is required?
Asked by Issacsim 8 years ago
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Verified Reply- SupplyHouse StaffYou can wire up to quantity four 24 volt thermostats into the Taco SR504-4. Please refer to the wiring guide supplied by Taco for any and all wiring instructions: https://s3.amazonaws.com/s3.supplyhouse.com/manuals/1351151766524/85275_PROD_FILE.pdf
Q: how to wire 4 zone switching relay to a zone valve
Asked by Dan 10 years ago
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Verified Reply- Supplyhouse StaffThe SR panels are meant to control 120VAC circ. pumps not zone valves, the ZVC panel is for valves.
Q: can two of these units be linked together to run two zones?
Asked by Dan 11 years ago
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Verified Reply- SupplyHouse StaffYes, there is also SR502-4 that will work for two zones.
Q: Am I correct in understanding the use of a multi-zone switching relay will eliminate the existing Honeywell relays, by permitting direct control of the circulators?
Asked by skip 11 years ago
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Verified Reply- Supplyhouse Staffyes it will
The Taco multi zone switching relay controls the circulators. It does not replace the Aquastat relay that ignites the boiler.
That is the way we set it up. We replaced the old relays with this Taco unit.
Q: power light is green and both zone lights are red. Is this correct?
Asked by Dave 11 years ago
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Yes, the power led light is green and the 2 zone led lights are red. Paul rothstein
Power light is always on. Zone light are only red when the zone is calling for heat.
As long as both zones are calling, this is correct
If both lights are red it means those zones are calling for heat Kristian Wolff Wolffsystems "I will always go left, when everybody else goes right"
The green power light should always be on. The red zone lights should come on and off as your thermostats call for heat - on indicates the call for heat from that zone.
Yes Sent from my Virgin Mobile phone.
Yes, that's correct.
Power light is green and zone lights are red only when circulators are on. This is how it should be. As each zone calls for heat the light turns red when the circulator turns on. I hope this helps you
Correct
Q: What do you do when one zone 1 pump does not turn on even when thermostat is calling
Asked by tech wanna b 12 years ago
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check your installation and settings on the unit. If all is okay, replace the unit. Mike
I'm pretty sure that control panel had led lights to show if pumps are turned in. Is tge corresponding light lit? If so is the 120 volts on pump terminals? If no led try to short out inputs where thermostat is connected if there's voltage on pump terminals you may have bad pump Kristian Wolff Wolffsystems "I will always go left, when everybody else goes right"
#1 Check the thermostat wire at the switching relay to make sure that the circuit is closed when the tstat is calling. (broken or disconnected tstat wire) #2 Check for 110v at output to pump at switching relay. (bad relay{little plastic cube}) #3 If you have 110v to pump the pump is bad
Q: I have this installed with one zone set for my radiant floor. Mercury thermostat and taco zone valve that zone. Can I add an high limit aquastat (Honeywell 6006) to that zone and wire it (low voltage) to turn on the taco zone valve even if the thermostat isnt calling? Essentially I am creating a high heat limit dump zone for my wood boiler. If the pipe temp reaches 180 degrees, the zone will open and flow to the radiant heat. Thanks for the help.
Asked by Scott 12 years ago
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Yes, I wonder though if your radiant has enough btu transfer for a dump zone. The mixing valve will greatly reduce the amount of hot water drawn off the boiler. I also found on my wood boiler that using digital aquastats ( I used Johnson Controls A -419) made the switching far more consistent. The mechanical aquastats vary a lot when switching. Mine control forced air blowers and the dump zone. The mechanical ones seem to vary as much as 6 or 7 degrees and are subject to sticking(?) I noticed this because they were frequently switching when I slammed the door or tapped on the aquastat. With the digital ones if you set them to switch at say 181 degrees it will switch at 181 degrees. The price has dropped since I bought mine also. About $65.00. Good Luck, Dan
Absolutely. The thermostat is normally open, and the SPDT on the 6006 can be wired that way. So, you can wire the single zone in parallel through both devices. To do this you would want (ideally) to source the 24VAC from a single source (the SR 506 or the thermostat). If you have to use separate 24VAC sources for each device I would recommend using two zones; one for the thermostat and one for the aquastat, then wire the zone valve in parallel to each zone (assuming you have spare zones). One caveat, many safety devices would normally be wired through the normally closed contacts so that a wire break looks like a safety event. Not really a good way to do that with the 506, you would need an interposing relay and that defeats the purpose.
Q: which relay is priority for my indirect hot water tank ? sr506-4 . thanks, gary
Asked by gary 12 years ago
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Zone 6. See here <http://s3.supplyhouse.com/manuals/13***.****6/85287_PROD_FILE.pdfc> .
the last zone, in your case zone 6 is the priority but there is a switch you must turn on so the priority is active top right side of circuit board
Q: Does this switching relay have a "primary" pump control? Im thinking of using a Primary/Secondary type system and I will need the Primary pump to start when ever one of the zones calls for heat.
Asked by Eric 12 years ago
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Some people call the boiler loop the primary and some call it the secondary. I prefer to call it the primary because the heat originates from there. Why isn't the boiler turning on the primary pump? The relay just closes the dry TT contacts that turn on the boiler which turns on the primary pump. The switching relay turns on the secondary pumps when the thermostats call for heat. Be sure and connect the primary loop to the secondary loop thru closely spaced T's to hydrolicly separate the two loops. (Prevent pump interference in the two loops.) Primary and secondary looping is used with high resistant to flow boilers. High head boilers.
NO Sent from my iPad
It will turn make the booker call for heat so just wire the primary circulator off of the boiler. Once a Tstat calls fir heat the secondary pump will start, once boiler starts then the primary pump will as well Kristian Wolff Wolffsystems
Sort of. Whenever any of the zones calls for heat the boiler start signal at X-X will be closed. This signal is intended to start the boiler, if you're not using it for boiler control you can use it to start a primary pump. The X-X signal is a control signal, it is not rated for full power to the pump like the zone relay outputs. If you don't need all 6 zones then you can use one of the zone relays for your primary. Connect the X-X contacts to the thermostat input for the zone you want to use for your primary. Then, whenever any zone calls for heat X-X will close, which in turn will be seen as a call for heat on the primary zone. When the other zones clear the X-X will open (the circuit doesn't seal itself), causing the primary to shut down. If you don't have a spare zone you can do the same thing with an external primary pump relay (the SR501 or pretty much any other suitable relay). If you also want to use the X-X signal for the boiler then it gets more complicated.
I am not sure it needs to have a primary pump relay. In a normal single-pump set-up, the thermostat gets wired into the boiler's control panel. When the thermostat calls for heat, the boiler closes the loop for the system pump, and water flows through the entire heating system. The way I set-up my system, I had three zone pumps on the secondary loop and a small circulator on the primary (boiler) side. The three zone pumps were wired into the switching relay, along with the respective zone thermostats. When a thermostat called for heat, it would signal the switching relay which does two things. 1) it closes the loop to the corresponding zone pump(s) and 2) it signals the boiler there is a call for heat, using the same wiring connection as the thermostat in a single zone system. So now when the switching relay signals to the boiler there is a call for heat (in lieu of the thermostat in a single-zone system), the boiler responds to the call for heat and powers the attached primary pump (which is the system pump in a single-zone system described above). Therefore, the primary-side pump is powered directly off the boiler's control panel and doesn't need a connection on the switching relay. I hope this makes sense and that it helped.
On further re-consideration. Do this. Get a switching relay that covers all the pump zones+primary pump. Wire this way--connect all the thermostats and secondary pump to the switching relay. Connect the dry TT contacts to the thermostat connection of the primary pump zone. I assume you are not connecting the dry TT contacts to a boiler. If so forget this idea. The boiler has it's own transformer and the switching relay has it's own transformer. Connecting the two voltages together may put them in reverse polarity. Not good. When the thermostats call for heat the secondary pump and the primary pump will turn on together.
To plainly answer your question, No! Can't be done. You need a single pump relay and a switching relay for the number of zones that you have. Connect the switching relay to the secondary pumps and the thermostats and the switching relay dry TT contacts to the primary single pump relay which will turn the primary pump on when the thermostats call for heat. Taco makes a pump that has a built in relay, I believe, eliminating the need for a single pump relay.
Q: I've had this unit about 6 years, operating two zones in the house. Zone 2 works perfectly. Zone 1 functions correctly when the thermostat calls for heat but there is now an unusual "clicking" noise at the relay unit that continues even as the hot water circulates. There is no clicking heard when zone 2 operates. Both zones accurately heat to thermostat settings. What is wrong and how do I fix it?
Asked by Cloud 12 years ago
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Sounds like relay chatter, which is likely one of two things: 1. The relay is dying - the coil could be losing its mojo. Easiest way to investigate is to pull the cover off the unit. The relays are standard ice-cube units, you could swap 1 and 2, if the problem moves to 2 then it is the relay. You could also swap 1 with 3 (which it sounds like you are not using), if the problem goes away you're done. If you haven't worked with these relays, they just pull straight out of the base, then get pushed back in. 2. The voltage to the relay coil is falling below the lower limit. Assuming you are using the built-in 24V supply and since zone 2 is working this would point to a bad connection or a bad thermostat switch. There could be just enough resistance that the voltage is right at the lower limit. If you are using a separate power supply then you would have to start there. Easiest way to test this is to disconnect the thermostat input for zone 1 and just connect a jumper directly at the controller. If the problem goes away then you know the problem is outside the box. If it doesn't go away (and your jumper connections are solid and clean) then the problem is inside the controller. See idea 1 above. If it is inside the unit you should be able to actually see the relays activate with the cover removed, if you see one cycling then you know the problem is with either that relay or the wiring to it.
If both t-stats are powered by the same 24volt transformer, that rules out the transformer. If each t-stat has its own it's possible that that unit is intermittent, use a digital voltmeter to confirm if voltage is not constant. If voltage is steady, (24~28v). Relay is defective. If you have a spare zone move leads to that zone. Maybe relay can be replaced without replacing the entire unit. Bob. Sent from my iPad
Here is a guess: Does the red light for zone 1 blink when it clicks? 1 If so, you might have a problem with the thermostat or the wire. Try swapping thermostats - top rule out a thermostat problem Try putting a jumper on the Zone 1 thermostat connection- to rule out a faulty wire 2 If it does not blink you may have an internal problem with the relay - unusual, but possible. Try swapping the relay cubes for zone 1 with one of the others. Try moving the thermostat wire and the circulator wire to zone 3 if not is unused. Has any electrical work been done on or near the heating system? I have seen relays click and chatter when they get backfed voltage from another circuit This could happen on the low voltage or the line voltage side Are the thermostats the same? battery powered?