MVVS1.5 | Vacuum Switch 1.5, 435 PSI, 220V 16A

MVVS1.5 | Vacuum Switch 1.5, 435 PSI, 220V 16A

The MVVS1.5 Vacuum Switch is a safety-critical accessory designed to
protect electric pressure washers and hot-water systems that draw from a bulk
water tank. Set to trigger at approximately 1.5″ Hg of vacuum, this
normally-open switch closes when suction is present at the pump inlet and opens
when flow stops or the tank runs dry. By interrupting power to the burner,
heater, or control circuit whenever water supply is lost, the MVVS1.5 helps
prevent catastrophic dry-running, overheating, and component damage in
tank-fed pressure washing systems. :contentReference[oaicite:0]{index=0}

• Normally-open vacuum switch designed to close when pump vacuum is detected.
• Re-opens when the pump stops drawing water or the tank level drops too low.
• Recommended for electric pressure washers up to 3 GPM flow. :contentReference[oaicite:1]{index=1}
• Helps protect pumps, burners, and coils from dry-run and low-water conditions.
• Compatible with many AR / Mecline / hot-water skid and cabinet-style systems.

How the MVVS1.5 Works

Installed on the inlet side of a pump, the MVVS1.5 monitors vacuum created as
the pump draws water from a tank. During normal operation, suction at the
inlet side causes the internal diaphragm to move and close the switch
contacts, completing the electrical circuit to the burner or control relay.
When flow stops, the vacuum dissipates, the diaphragm returns to its rest
position, and the switch opens, breaking the circuit and shutting down the
burner or other controlled device. :contentReference[oaicite:2]{index=2}

Operating sequence

• Water present, pump ON: inlet vacuum reaches 1.5″ Hg or more, switch closes, burner/relay circuit is enabled. :contentReference[oaicite:3]{index=3}
• Flow stops or tank runs dry: vacuum drops, diaphragm rises, spring returns switch to open position.
• Open switch: burner or solenoid circuit is interrupted, fuel supply closes and firing stops. :contentReference[oaicite:4]{index=4}
• Restores automatically when water supply returns and vacuum is detected again.

Construction and Ratings

The MVVS1.5 is built as a compact, rugged assembly suitable for mounting in
the frame or cabinet of professional pressure washers. It uses a
vacuum-sensing diaphragm, internal spring, and electrical contacts sized for
typical burner or control loads. The switch is commonly supplied as a
220–230 V AC, 16 A rated device, giving ample capacity for
most burner control circuits and contactor coils. :contentReference[oaicite:5]{index=5}

• Vacuum setpoint: 1.5″ Hg. :contentReference[oaicite:6]{index=6}
• Electrical rating: up to 220–230 V AC, 16 A (typical contact rating). :contentReference[oaicite:7]{index=7}
• Contact type: normally open; closes on vacuum, opens on loss of vacuum. :contentReference[oaicite:8]{index=8}
• Hydraulic connection: 1/4″ FPT (female pipe thread) inlet / port. :contentReference[oaicite:9]{index=9}
• Max water temperature: around 131–176°F (55–80°C), depending on system rating. :contentReference[oaicite:10]{index=10}
• Typical system limits: often paired with pumps to ~2,600 PSI and up to ~6.7 GPM. :contentReference[oaicite:11]{index=11}
• Approximate weight: about 1.25 lb. :contentReference[oaicite:12]{index=12}

Design advantages

• Compact form factor for easy mounting in hot-water skids and cabinet units.
• Mechanical diaphragm design—no complex electronics or logic boards.
• Field-proven Mecline / AR pattern used widely in professional washers. :contentReference[oaicite:13]{index=13}
• Simple wiring: two contacts wired in series with burner or safety circuit.

System Integration

The MVVS1.5 is most commonly installed on tank-fed electric pressure
washers where system safety depends on verifying water supply before
enabling heat. It is typically wired in series with flow switches, thermostats,
pressure switches, and other safeties to create a layered interlock chain for
the burner or heating element.

• Intended for electric pressure washers up to 3 GPM from a gravity or float tank. :contentReference[oaicite:14]{index=14}
• Mounts in the suction line where pump inlet vacuum can be sensed reliably.
• Works alongside flow, pressure, and temperature switches as part of a burner safety loop.
• Can be used to control solenoids, contactors, or burner primary controls. :contentReference[oaicite:15]{index=15}

Typical wiring concept

• Hot feed passes through emergency stop, pressure switch, flow switch, and vacuum switch in series.
• Only when all safety devices are “made” does power reach the burner control or solenoid.
• Loss of water (no vacuum) instantly opens the MVVS1.5 and removes power from the burner circuit.

Typical Applications

MVVS1.5 | Vacuum Switch 1.5, 435 PSI, 220V 16A

Because it combines simple mechanical construction with proven reliability,
the MVVS1.5 appears in a wide range of professional pressure washing and
industrial cleaning equipment.

• Electric hot-water pressure washers fed from overhead or tote tanks.
• Cabinet-style parts washers that require verified inlet water before heat is enabled.
• Trailer and skid rigs using bulk water tanks with burner-equipped pump sets.
• Industrial wash bays where operators may frequently stop and start flow.
• Rental fleet machines where robust low-water protection reduces costly pump failures.

Key Specifications – MVVS1.5 Vacuum Switch

• SKU: MVVS1.5
• Type: vacuum-actuated, normally-open safety switch.
• Vacuum setpoint: 1.5″ Hg (closes on vacuum). :contentReference[oaicite:16]{index=16}
• Recommended flow range: electric pressure washers up to ~3 GPM. :contentReference[oaicite:17]{index=17}
• Electrical rating: up to ~220–230 V AC, 16 A contacts (check nameplate). :contentReference[oaicite:18]{index=18}
• Connection: 1/4″ FPT vacuum inlet / port.
• Max water temperature: typically 131–176°F (55–80°C), depending on model. :contentReference[oaicite:19]{index=19}
• Ambient rating: up to around 131°F (55°C) environment temperature. :contentReference[oaicite:20]{index=20}
• Typical system limits: up to ~2,600 PSI and 6.7 GPM when used in approved configurations. :contentReference[oaicite:21]{index=21}
• Approximate weight: about 1.25 lb.