Honeywell Zone Valve V8043 24V Wiring Diagram

Honeywell Zone Valve V8043 24V Wiring Diagram

Honeywell Zone Valve V8043 24V Wiring Diagram

5/5 (1👤)
🌡️ HVAC & Water Heating 🧮 14 schematics
★Rate It★
🧮 Diagram 🖨️ Print 📖 Instructions 🛠️ Troubleshooting 💬 FAQs

How many stars do you give this diagram?

Single valve

Typical wiring for one valve with its thermostat, transformer and end switch.

Single valve
TO LINEV8043EyellowredL1 (HOT)L2THERMOSTATMOTORAUXILIARYSWITCHTO CIRCULATOR ORANOTHER VALVEV8043FEND SWITCHTH-TRTHTRTHERMOSTATL1 (HOT)L224 V TRANSFORMERTO CIRCULATOR ORANOTHER VALVE

Terminals and components · 4

  • Transformer
  • Thermostat
  • Motor
  • End switch

About This Diagram

These diagrams are redrawn from pages 4–8 of the Honeywell Zone Valve V8043 24V manual, and we offer them completely free and in English. We have also categorized it in the Boilers & Zone Valves (HVAC & Water Heating) section on Diagramverse, and it has been rated by 1 user with an average rating of 5.0. If you have any specific questions about the Honeywell Zone Valve V8043 24V Wiring Diagram, we suggest checking the Frequently Asked Questions (FAQs) section.

Printable Honeywell Zone Valve V8043 24V Wiring Diagrams

Complete · V8043E (leadwires)

1 / 14
Honeywell Zone Valve V8043 24V Wiring Diagram – Complete · V8043E (leadwires)
Honeywell Zone Valve V8043 24V Wiring Diagram – Complete · V8043F (terminal board)
Honeywell Zone Valve V8043 24V Wiring Diagram – T822 zones · V8043A
Honeywell Zone Valve V8043 24V Wiring Diagram – T822 zones · V8043E + L4006A
Honeywell Zone Valve V8043 24V Wiring Diagram – T822 zones · V8043E + Aquastat
Honeywell Zone Valve V8043 24V Wiring Diagram – T87F zones · L8124G
Honeywell Zone Valve V8043 24V Wiring Diagram – T87F zones · W775A panel
Honeywell Zone Valve V8043 24V Wiring Diagram – T87F zones · AT87A transformer
Honeywell Zone Valve V8043 24V Wiring Diagram – Replacements · Taco · E
Honeywell Zone Valve V8043 24V Wiring Diagram – Replacements · Taco · F
Honeywell Zone Valve V8043 24V Wiring Diagram – Replacements · Dole/Flair · E
Honeywell Zone Valve V8043 24V Wiring Diagram – Replacements · Dole/Flair · F
Honeywell Zone Valve V8043 24V Wiring Diagram – Replacements · W-Rodgers · E
Honeywell Zone Valve V8043 24V Wiring Diagram – Replacements · W-Rodgers · F

Wiring Instructions

Before you start

First, pick the Honeywell Zone Valve V8043 24V tab that matches your installation. Use Complete for a single valve with its own transformer and thermostat. In that tab, choose V8043E (leadwires) if your valve has flying leads or V8043F (terminal board) if it has screw terminals. For multizone systems, use T822 zones or T87F zones and pick the variant that matches your boiler control, zone panel or extra transformer. Use Replacements when a 2-wire V8043E or V8043F is taking the place of a 3-wire Taco, Dole, Flair or White-Rodgers valve.

  • Tools: screwdrivers, a wire stripper, wire nuts, electrical tape, labels and a multimeter that reads AC volts and continuity.
  • Wire: No gauge is specified for this valve. 18 AWG thermostat cable is the usual choice for the 24 V wiring. Any wiring that carries 120 V, such as end switch circuits feeding a circulator, must be line-voltage wire sized for that circuit. All wiring must meet local codes.
  • Transformer capacity: Each valve draws 0.30 A, 7.2 VA maximum, at 24 V AC 60 Hz. Add 7.2 VA for every valve on the same transformer, plus any other 24 V loads it already powers.
  • End switch load: The end switch is rated 120 V, 4.4 A running and 26.4 A inrush, or 50 VA pilot duty at 24 V. Compare these figures with the nameplate of the circulator or relay it will switch.

Turn off the breaker or disconnect that feeds the transformer, the boiler and the circulator. Then confirm with your meter that the circuit is dead. Every line-voltage supply needs a disconnect and overload protection. This work is meant for a trained, experienced service technician. If you need a new 120 V circuit or changes inside the boiler's control wiring, hire a licensed electrician or heating contractor, and check whether your area requires a permit.

Step-by-step wiring

  1. Confirm the valve is mounted with the flow in the direction of the arrow on the body. On horizontal pipe, the actuator must sit level with or above the pipe centerline. When replacing a valve, label every old wire with the letters shown in the Replacements tab before you disconnect it, and note its position and color.
  2. Connect the 24 V transformer primary to L1 (hot) and L2 through its disconnect.
  3. Wire the 24 V control loop. On a V8043E, run one transformer secondary lead to the thermostat. Run the thermostat's other wire to one yellow lead, and connect the second yellow lead to the other secondary lead. On a V8043F, land one secondary lead on TH-TR and connect the thermostat between TH-TR and TH. Then run the other secondary lead to TR. TH-TR is only a tie point and does not connect to the motor.
  4. For multiple zones, one transformer side feeds all the thermostats and the other side goes to one motor lead, or TR, on each valve. On a V8043A, the black lead goes to the thermostat. If the total load exceeds your transformer, an AT87A transformer powers up to five more valves, and each additional W775A panel powers up to four more.
  5. With an L8124G aquastat, follow that variant exactly, including the jumper added on each valve. With a W775A panel, wire each zone to its own row: thermostat on R and W, TH to BR, TR to W, and the end switch to the zone's two B terminals.
  6. Wire the end switch: the two red leads on a V8043E, or the two top terminals on a V8043F. On a single valve, it starts the circulator or another valve. In multizone systems, wire all end switches in parallel so that any open zone runs the circulator and burner. In the L4006A variant, the red leads connect to L1 (120 V) and the L4006A. In the aquastat and Dole/Flair variants, they go to the T-T terminals.
  7. For a White-Rodgers replacement, use thermostat terminals 6 and 4. Tape the unused wire from terminal 5 and tuck it away. If the old transformer also powered the auxiliary circuit, use the alternate wiring shown for that case.
  8. Tighten every connection and tug-test each wire nut. Keep the 24 V wiring physically separated from the 120 V wiring, then refit the actuator cover.

Testing and start-up

Restore power and measure the transformer secondary; it should read about 24 V AC. Raise the zone thermostat above room temperature. The valve should open smoothly. At the end of the opening stroke, the end switch should close and the circulator or burner circuit should start. While the thermostat is calling, you should read about 24 V AC across the two yellow leads, or across TH and TR.

Lower the setpoint below room temperature. The spring should close the valve, the voltage across the motor should drop to zero and the auxiliary equipment should stop. Repeat this on every zone, and check that each valve goes from closed to open and back to closed without sticking. If you opened the valve by hand, the manual lever releases automatically the first time the motor is powered.

Safety notes

  • The transformer primary and, in many layouts, the end switch carry 120 V even though the thermostat side is 24 V. Treat the red leads as live unless you have confirmed otherwise.
  • Never jumper the motor terminals, not even briefly. Doing so can burn out the heat anticipator in the thermostat.
  • Do not exceed the end switch rating. As a general rule, use a properly rated relay for any load larger than the rating.
  • Keep the valve where the ambient temperature stays at or below 125°F and the fluid stays at or below 200°F.

Troubleshooting

Symptom Probable Cause What to Check
Nothing happens when the thermostat calls: the valve doesn't move and there's no hum No 24 V: tripped breaker, open disconnect, or the transformer primary isn't wired to L1 and L2 Measure the transformer secondary; you should read about 24 V AC. If it reads zero, check for 120 V on the primary and inspect the breaker and disconnect.
The transformer has power, but a V8043F valve won't open on a call for heat The thermostat is landed on TR instead of TH, or the transformer lead is on TH instead of the TH-TR tie terminal With the thermostat calling, measure across TH and TR; it should read about 24 V AC. Rewire so that the transformer goes to TH-TR, the thermostat runs between TH-TR and TH, and the other transformer side goes to TR.
The valve opens but the circulator or burner never starts The end switch isn't wired, is wired to the wrong terminals, or the auxiliary circuit has no power With the valve fully open and the power off, check continuity across the red leads or the two top end switch terminals; they should read closed. Then confirm the circuit they feed has its supply, for example L1 or the T-T terminals.
I opened the valve with the lever and the pump doesn't run Normal: the end switch does not close when the valve is opened manually Use the thermostat to open the valve. The lever releases on the next electrical operation, and the end switch then closes at the end of the opening stroke.
Only one zone starts the circulator, or the pump runs only when all zones call End switches wired in series, or only one zone's end switch is connected Rewire all end switches in parallel to the circulator or burner circuit. Test each zone on its own: every zone should start the circulator.
The valve stays open after the thermostat is satisfied A short or jumper across the thermostat wires or motor leads, or the lever is locked at MAN. OPEN With the thermostat satisfied, measure across the motor leads; it should read 0 V. Look for a nicked cable or leftover jumper, and check the lever position.
The thermostat stopped controlling after someone jumpered the valve wires The thermostat's heat anticipator burned out Repair or replace the thermostat, and never jumper the valve coil terminals again.
Valves open slowly or not at all when several zones call, and the transformer runs hot The transformer is undersized for the number of valves Add 7.2 VA per valve and compare the total with the transformer's VA rating. Measure the secondary with all zones calling. Add an AT87A transformer or another W775A panel if needed.
The new valve runs nonstop or ignores the thermostat after replacing a 3-wire valve Old wires were mismatched, or terminal 5 on a White-Rodgers thermostat was left connected Match every wire to its letter in the Replacements variant for your old brand. On White-Rodgers systems, use terminals 6 and 4 only, and tape the wire from 5.
The end switch contacts are pitted or the circulator stutters The circulator draws more than the end switch rating Check the circulator nameplate against 4.4 A running and 26.4 A inrush at 120 V. If it's higher, switch the circulator through a properly rated relay.
Zones open but the boiler never fires, in a system with an aquastat The red leads aren't on the aquastat's T-T terminals Confirm the end switches are in parallel on T-T. With a zone open, check continuity across T-T at the aquastat; it should read closed.

Frequently Asked Questions (FAQs)


What is the difference between the V8043A, V8043E and V8043F?
The V8043A has leadwires and no end switch, the V8043E has leadwires plus an end switch, and the V8043F has a screw terminal board plus an end switch. On the E, the motor uses the two yellow leads and the end switch uses the two red leads. On the F, the motor connects to TH and TR, and the end switch uses the two top terminals. Choose E or F if the valve itself needs to start a circulator or burner. The A suits systems where something else handles that.

Can I mix V8043E and V8043F valves in the same system?
Yes. If your local code permits, the V8043E and V8043F can be used interchangeably when each is wired as shown for its type. The yellow leads of the E do the same job as TH and TR on the F, and the red leads match the F's end switch terminals. Wire each valve from its own variant in the diagram, and keep all end switches in parallel so that any zone can start the circulator.

What size transformer do I need for my zone valves?
Allow 7.2 VA for each V8043 valve on the transformer. Three valves need at least 21.6 VA, plus anything else the transformer already powers. Each valve draws 0.30 A at 24 V AC. When one transformer can't handle all the zones, an AT87A transformer powers up to five more valves, and each additional W775A panel, which has its own transformer, handles up to four more. Check the VA rating printed on your transformer before adding zones.

What is the TH-TR terminal on the V8043F for?
TH-TR is a tie terminal that joins the transformer lead to one side of the thermostat. It is not connected to the motor. The thermostat wires between TH-TR and TH, and the other transformer lead goes to TR, so the motor gets 24 V across TH and TR only when the thermostat closes. In replacement wiring the tie point is optional, but using it keeps the splice neat and inside the terminal enclosure.

Can the end switch run my 120 V circulator directly?
Often it can, but only within its rating: 120 V, 4.4 A running and 26.4 A inrush, or 50 VA pilot duty at 24 V. Check your circulator's nameplate. If the running or starting current is higher, have the end switch drive a relay or the boiler's T-T terminals instead, which is general good practice for larger pumps. Remember that when the end switch switches 120 V, the red leads are live whenever the circuit is energized.

Can I replace a 3-wire Taco, Dole, Flair or White-Rodgers valve with a V8043?
Yes. A 2-wire V8043E or V8043F can replace these 3-wire valves using the existing transformer and thermostat wiring. Select your old brand and the E or F variant in the Replacements tab, and match each lettered wire before connecting. White-Rodgers systems use thermostat terminals 6 and 4, with the wire from 5 taped off. Also confirm that the V8043's pressure rating suits your system, since it differs between models.

Is the V8043 normally open or normally closed?
The V8043 is normally closed. With 24 V applied to the motor it opens, and when power is removed an internal spring closes it. This means a power failure leaves the zone closed. If you need heat without power, move the manual lever slowly and firmly to MAN. OPEN, where the stop holds it. The valve returns to automatic operation the next time it is energized.

Which thermostats work with the V8043?
The typical choices are the T87F and T822, and the diagram shows both. Any heating thermostat that switches a 24 V circuit and can handle the valve's 0.30 A current should work. If your thermostat has an adjustable heat anticipator, set it according to the thermostat maker's instructions for the current it switches. Smart thermostats may need a common wire for their own power, so check their requirements before wiring.

Can I leave the valve energized all the time?
You can, but it's not recommended. The valve is designed for normal on-off cycling, and keeping the motor powered continuously shortens its life. If a zone needs to stay open for a long period, for example during service, the manual lever is a better option. Keep in mind that the end switch does not close when the valve is opened by hand, so the circulator won't start from that zone.

Can I use the V8043 with glycol, potable water or steam?
It is suitable for closed hydronic systems with water or a glycol/water mix of up to 50:50. It is not for potable water, steam or oxygenated water. Systems with frequent make-up water carry dissolved oxygen, which wears out the rubber plug inside the valve until it fails. Fluid temperature must stay at or below 200°F, and the maximum system pressure is 300 psi.

Related Product Diagrams

Go up