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MDI Mercury parts are essential for dependable switching and load control in HVAC applications. They include contactors, mercury relays, coils, and steel strap connectors for accurate performance. These parts help ensure efficiency, prevent electrical failures, and extend the overall service life of equipment.
-13%MDI Mercury Displacement 35NO-277A 1-Pole Contactor 277VSpecial Price $109.48 Regular Price $125.90
-13%MDI Mercury Displacement 230NO-220AU 2-Pole Contactor 30 AMP 208/240VSpecial Price $115.05 Regular Price $132.31
-13%MDI Mercury Displacement 335NO-120A ContactorSpecial Price $178.13 Regular Price $204.85Out of stock
-13%MDI Mercury Displacement 35NO-120AT Mercury Displacement Contactor Top Terminals 120VSpecial Price $66.14 Regular Price $76.06Out of stock
-13%MDI Mercury Displacement 35NO-277AH 1-Pole N/O Contactor 35A 277VSpecial Price $85.86 Regular Price $98.74Out of stock
-13%MDI Mercury Displacement 35NO-24DH Mercury Contactor 24VDCSpecial Price $62.06 Regular Price $71.36Out of stock
-13%MDI Mercury Displacement 35NO-24A 1-Pole N/O Contactor 24VSpecial Price $69.14 Regular Price $79.51Out of stock
-13%MDI Mercury Displacement 35NO-120ATB N/O Contactor Top Terminal 35A 120VSpecial Price $75.87 Regular Price $87.26Out of stock- -13%MDI Mercury Displacement 335NO-24-18 Contactor Steel StrapSpecial Price $178.13 Regular Price $204.85Out of stock
- -13%MDI Mercury Displacement 235NO-24A-18 2-Pole Contactor 35 AMP 24V CoilSpecial Price $130.07 Regular Price $149.58Out of stock
MDI Mercury Parts for HVAC Appliance Replacements
MDI Mercury replacement parts are designed to provide reliable switching and load control in HVAC systems. These components, such as contactors, relays, and coil units, ensure smooth electrical operation and consistent performance. By managing power flow safely and efficiently, they protect equipment from failures and extend system life.
When parts begin to fail, systems may show inconsistent power delivery or unexpected equipment shutdowns. Flickering displays or irregular thermostat responses can also signal failing parts within the system. Faulty contactors may stick or chatter, leading to unstable operation and potential overheating risks. Signs such as burnt odors or persistent buzzing noises often indicate deteriorating components.
At PartsHnC, availability meets reliability with every replacement part you’re searching for. We provide top-quality, trusted parts, including 1-pole 277V, 2-pole 35A 24V coil, 30A 208/240V, 120V top terminal, 24VDC, steel strap models, and more.
FAQs
What causes frequent chattering in mercury relays?
Relay chatter often results from weak coil voltage, loose connections, or deteriorating mercury displacement contacts.
Why does my system shut down under heavy load?
Defective MDI mercury contactors fail to handle rated amperage, causing overheating and unexpected system shutdown.
How do I troubleshoot overheating mercury contactors?
Check coil resistance, terminal tightness, contact surface integrity, and rated load compliance immediately.
What should I do if my breaker keeps tripping when the HVAC runs?
Breaker trips usually mean damaged mercury contacts are overheating; swapping parts restores normal system operation.
Why does my HVAC unit smell like something is burning?
Overheated coils or failing relays can burn insulation; replace them quickly to avoid serious damage.
How do I fix flickering power in my HVAC unit?
Flickering power suggests failing relays interrupt current; fresh replacements ensure consistent power flow.