--- product_id: 745060045 title: "SUPCO SPP6 Relay/Capacitor Hard Start Kit with 500% Increase Starting Torque by Sealed Unit Parts Co., Inc." brand: "supco" price: "£16.24" currency: GBP in_stock: false url: https://www.desertcart.co.uk/products/745060045-supco-spp6-relay-capacitor-hard-start-kit-with-500-increase store_origin: GB region: United Kingdom --- # 500% boost in starting torque No batteries required, maintenance-free Plug-and-play relay/capacitor design SUPCO SPP6 Relay/Capacitor Hard Start Kit with 500% Increase Starting Torque by Sealed Unit Parts Co., Inc. **Brand:** supco **Price:** £16.24 **Availability:** ❌ Out of Stock ## Summary > ⚡ Power up your HVAC game with unstoppable starting torque! ## Quick Answers - **What is this?** SUPCO SPP6 Relay/Capacitor Hard Start Kit with 500% Increase Starting Torque by Sealed Unit Parts Co., Inc. by supco - **How much does it cost?** £16.24 with free shipping - **Is it available?** Currently out of stock - **Where can I buy it?** [www.desertcart.co.uk](https://www.desertcart.co.uk/products/745060045-supco-spp6-relay-capacitor-hard-start-kit-with-500-increase) ## Best For - supco enthusiasts ## Why This Product - Trusted supco brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **Durable Build:** Crafted from robust ABS material ensuring long-lasting performance and reliability. - • **Seamless Compatibility:** Specifically engineered for permanent split capacitor single-phase A/C and heat pump systems. - • **Effortless Installation:** Compact, lightweight design (136g) makes upgrades quick and hassle-free. - • **Energy Efficient Upgrade:** Boost system efficiency without adding extra power draw or maintenance. - • **Turbocharge Your Compressor:** Experience a staggering 500% increase in starting torque for faster, smoother startups. ## Overview The SUPCO SPP6 Hard Start Kit delivers a 500% increase in compressor starting torque, designed for permanent split capacitor single-phase A/C and heat pump systems. Lightweight and made from durable ABS, it offers an easy, maintenance-free installation that enhances system reliability and efficiency. ## Description Relay/Capacitor Hard Start Kit 500% INCR STARTING TORQUE; Increased Compressor Starting torque. Designed for use on permanent split capacitor single phase A/C and heat pump systems; the country of origin is China ## Features - SUPCO SPP6 relay/Capacitor Hard Start Kit with 500% increase starting torque ## Technical Specifications | Specification | Value | |---------------|-------| | Part number | SPP6 | | Item Weight | 136 g | | Product Dimensions | 16.51 x 18.42 x 16.51 cm; 136.08 g | | Is Discontinued By Manufacturer | No | | Material | Acrylonitrile Butadiene Styrene (ABS) | | Voltage | 230 Volts | | Batteries Included | No | | Batteries Required? | No | | Item Dimensions LxWxH | 16.5 x 18.4 x 16.5 cm | ## Product Details - **Capacitance:** 6 Microfarad - **Material:** Acrylonitrile Butadiene Styrene (ABS) - **UPC:** 687152031528 687152197361 ## Images ![SUPCO SPP6 Relay/Capacitor Hard Start Kit with 500% Increase Starting Torque by Sealed Unit Parts Co., Inc. - Image 1](https://m.media-amazon.com/images/I/71wgg5wU+zL.jpg) ![SUPCO SPP6 Relay/Capacitor Hard Start Kit with 500% Increase Starting Torque by Sealed Unit Parts Co., Inc. - Image 2](https://m.media-amazon.com/images/I/7162p8bSyDL.jpg) ![SUPCO SPP6 Relay/Capacitor Hard Start Kit with 500% Increase Starting Torque by Sealed Unit Parts Co., Inc. - Image 3](https://m.media-amazon.com/images/I/719JrXrxE5L.jpg) ![SUPCO SPP6 Relay/Capacitor Hard Start Kit with 500% Increase Starting Torque by Sealed Unit Parts Co., Inc. - Image 4](https://m.media-amazon.com/images/I/71a8PcI2EgL.jpg) ![SUPCO SPP6 Relay/Capacitor Hard Start Kit with 500% Increase Starting Torque by Sealed Unit Parts Co., Inc. - Image 5](https://m.media-amazon.com/images/I/31LvJXYzB6L.jpg) ## Questions & Answers **Q: I live in Az.I need a hard start kit for a 30,000 btu 2.5 ton,which one do you recommend?** A: The Supco uses a Positive Temperature Coefficient Relay (as stated on their website) not a Potential Relay. Not Good! Only use Hard Start Kits that use a true Potential Relay. The RectorSeal Kickstart (2 wire) and the 5-2-1 Compressor Saver (3 wire) hard start kits use a Potential Relay. I recommend the Kickstart (it uses 2 wires that connect to the Run Capacitor - HERM and COM). But the Compressor Saver is also good (3 wires with one connecting to the common / ground on the Contactor relay). They both work the same way - the Potential Relay detects the pickup voltage (back EMF). This causes the relay to disconnect the start capacitor when the compressor reaches about 75% speed (usually less than a second). Note: Supco does have hard start kits with a Mechanical Potential Relay (Models 3W1, 3W2, & 3W3) but they are not available on Amazon. **Q: If there is an existing start capacitor, can you put this one in parallel with it or the run capacitor?** A: This takes the place of the start capacitor. It gives an old compressor a "punch" as it starts and it immediately goes out of the start up circuit. They work! It is wired in parallel with the run capacitor, which stays in teh circuit so your compressor will run more efficiently..electrically speaking. **Q: Can a hard start kit help an a/c compressor start when powered by a generator which more than satisfies the unit's FLA but is just shy of the LRA?** A: Greetings,I use these for my rental apartment AC units they keep these old units running and starting easy! They need to be checked every 2 year or so. If you are just shy of the Locked Rotor Amperage; The amperage the motor draws when the voltage is first applied to the motor and the rotor has not started to turn. This amperage is usually up to 300% of the motors running amperage. Once the rotor starts to turn the motor generates a back EMF (electro motive force) that opposes the high inrush current. This back EMF drives the amperage down until the motor gets up to its rated speed at which time the motor amperage will be at its run amperage. This device helps starting and should make you successful. Make sure that your line voltage is being properly supplied during the high current peak that you have proper AWG for the load and length from your generator to your compressor as it could be a voltage drop issue.Never the less a good part and should help.Best of LuckDarrell **Q: Is this pretty easy to install? Is it just removing two wires from the old capacitor and reattaching to the new hard start capacitor? Thanks.** A: The hard start cap installs in parallel with the old cap. You connect one wire to the common and one wire to the herm terminals on the old cap. This just gives the compressor an extra kick. I would recommend that you get the 5-2-1 hard start kit instead. I have tried both and the 5-2-1 works better. Just search on Amazon for 5-2-1 hard start kit. ## Frequently Bought Together - SUPCO SPP6 Relay/Capacitor Hard Start Kit with 500% Increase Starting Torque - VEXUNGA 45/5 uF 45+5 MFD 370V or 440V Dual Run Start Round A/C Capacitor 45 5 uF 370 440 Volt VAC CBB65B Air Conditioner Capacitors for AC Unit Fan Motor Start or Heat Pump or Condenser Straight Cool - TITAN PRO, 1 Count (Pack of 1), No Color Packard TRCFD455 45+5MFD 440/370V Round Run Capacitor Replaces PRCFD455 --- ## Why Shop on Desertcart? - 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016 - 🌍 **Shop Globally** — Access 737+ million products across 21 categories - 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price - 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members) - 🔒 **Secure Payments** — Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.co.uk/products/745060045-supco-spp6-relay-capacitor-hard-start-kit-with-500-increase](https://www.desertcart.co.uk/products/745060045-supco-spp6-relay-capacitor-hard-start-kit-with-500-increase) --- *Product available on Desertcart United Kingdom* *Store origin: GB* *Last updated: 2026-05-19*