Kilrock Big K Multi-Purpose Descaler - 400ml



Kilrock 2 for £8 Mix and Match

In Stock

Product code: 126396  | Model: BIGK
Want it by tomorrow? Order within and select Next Day Delivery at checkout.
    Why buy from Robert Dyas?
  • Home Delivery to most of UK Mainland Delivered within 5 working days from £3.95
    Next working day: £4.95
    Named day: £4.95
    Saturday: £7.95
    Find out more
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This Kilrock limescale remover is a brand leader that totally clears even heavily scaled appliances in just 5 minutes.

It removes hard water drip stains quickly and effectively from baths and taps and is ideal to use with metal or plastic kettles, shower heads, coffee makers, steam irons and toilets.

This is the original 5 dose multi-purpose descaler with a unique biodegradable, phosphate-free formula has been descaling kettles for over 70 years: nothing performs like it!

You'll get your home de-scaled in no time at all with this limescale remover by your side!

Features and Benefits

  • Descales in five minutes – This limescale remover can rid appliances from heavy limescale in just five short minutes.
  • Removes hard water drip stains – Great for use on baths, taps, metal or plastic kettles, shower heads and more. 
  • Phosphate-free – Phosphates are known to be bad for health and very damaging to the environment, so being phosphate-free is a great bonus for both you and the planet. 


  • Made in the UK
  • 400ml provides 5 doses
  • Phosphate-free

How To Use

  • Metal or plastic kettles: Half fill the kettle with water and bring to the boil
  • Stand kettle in a bowl in the sink in case of excess fizzing
  • Add 1 measure of Kilrock-K and leave for 5 mins or until the fizzing stops
  • Pour away contents, reboil kettle and pour away and rinse before reuse
  • Wash off any spillage
  • Shower heads: Mix one part Kilrock-K and 8 parts warm water in a bowl
  • Immerse head in solution until fizzing stops
  • Rinse head and bowl in cold water before reuse
  • Coffee makers: Refer to manufacturers handbook
  • Mix one part Kilrock-K and 8 parts warm water and carefully add to the appliance reservoir
  • Switch on and run as normal. Empty and repeat process twice with clean water
  • Steam irons: Mix one part Kilrock and 8 parts warm water in a jug
  • Warm iron and unplug
  • Pour solution into chamber to normal level
  • Place an upturned saucer in a plastic bowl and place the iron, soleplate down, on the saucer
  • Depress the steam button until all the solution is used. Repeat process with cold water
  • Wipe soleplate and iron ready to use
  • Toilet pans: Add 1 litre of hot tap water to the pan
  • Pour 2 measures of Kilrock-K into the pan
  • Leave until it stops fizzing. Brush and flush


  • Contains Formic Acid


We aim to deliver items that are currently in stock within five (5) working days (excluding Bank Holidays) after the date the order is placed.

Working days are defined as Monday-Friday 8am-7pm inclusive, excluding Saturday, Sunday and Public Holidays.

Please note that during particularly busy periods, it may take a little longer to receive your delivery and our carrier may attempt to deliver to you on a Saturday.


  Standard Next Day Named Day Saturday
Mainland UK (ex Isle of Wight) £3.95 £4.95 £4.95 £7.95
Highlands & Scottish Isles £11.95 N/A N/A N/A
Northern Ireland & Isles £11.95 N/A N/A N/A
Mainland UK (ex Isle of Wight):  
Standard: £3.95
Next Day: £4.95
Named Day: £4.95
Saturday: £7.95
Highlands & Scottish Isles:  
Standard: £11.95
Next Day: N/A
Named Day: N/A
Saturday: N/A
Northern Ireland & Isles:  
Standard: £11.95
Next Day: N/A
Named Day: N/A
Saturday: N/A

Next Day service will be available for orders placed on the website from Monday to Thursday before 3pm. Typical delivery time windows: Standard, Next Day, Named Day - 08:00 - 16:00

Our Saturday service is available for orders placed before Friday 3pm. Typical delivery time window: Saturday - 08:00 - 18:00


  Next Day Named Day Saturday
Mainland UK (ex Isle of Wight) £15.00 £15.00 £25.00
Mainland UK (ex Isle of Wight):  
Next Day: £15.00
Named Day: £15.00
Saturday: £25.00

Next Day service will be available for orders placed on the website from Monday to Thursday before 3pm. Typical delivery time windows: Next Day, Named Day - 08:00 - 18:00

Our Saturday service is available for orders placed before Friday 3pm. Typical delivery time window: Saturday - 08:00 - 18:00

Unfortunately, we currently cannot deliver bulky products to the following locations: Highlands & Scottish Isles, Isle of Man & Isles of Scilly, Northern Ireland, Isle of Wight


Some of the items sold on our website are delivered direct from our suppliers; this is clearly indicated on the relevant product page. Lead times for these items do vary from 5 working days up to 28 days. Please be aware that we can only arrange for delivery of these products to mainland UK addresses. Vendor direct products are delivered for FREE.


Returning an item couldn't be simpler with our 30 day money back guarantee:

Most of our products are covered by our 30 day no quibble money-back-guarantee as long as they are with their original packaging, unused and in a resaleable condition.

This promise exceeds your legal rights under the Consumer Contracts Regulations

Products not covered by our 30 day money-back-guarantee

  1. Large Kitchen Appliances (including washing machines, cookers, dishwashers, fridge freezers, hobs, cooker hoods and dryers)
  2. Outdoor Garden Furniture
  3. Indoor Furniture
  4. Products delivered direct from our approved suppliers (this is highlighted on the product detail page)

To return an item, you can either:

  1. Visit your nearest store with your receipt and we’ll give you a refund or exchange.
  2. Download a returns form or use the form on your delivery and returns note, enclosed with your goods. We recommend you obtain proof of posting when returning your items.
  3. Email or call our Customer Services team at [email protected] or 0333 103 6677 and they will provide you with returns instructions.

See our Delivery and Returns section for more information.

Ratings & Reviews


89 Reviews

4.9 / 5 Quality

4.8 / 5 Value

Rating snapshot
  • 5 / 5Quality

    5 / 5Value

    22 August 2019

    Kilrock descaler,

    This product does everything it says on the label extremely efficiently. Very pleased with the results.

  • 4 / 5Quality

    4 / 5Value

    22 July 2019

    Wow! It works wonders

    BIG K - this really does a wonderful job of descaling. I have used other brands but none have been this efficient. Used on kettles and iron, and will now try other items in the home.

  • 5 / 5Quality

    5 / 5Value

    06 July 2019


    Went to eastleigh store bought this product, on the advice of of staff. What a clean kettle very good thanks.

  • 5 / 5Quality

    5 / 5Value

    25 June 2019

    Great Product - does what it says

    On a visit to our daughter's in Didcot, & visited the Robert Dyas store (our own home area doesn't have one, but I think that they are wonderful shops). Found all we were looking for, & then at the counter I was recommended this product - & descaler was something else we were going to get elsewhere. Descaled our daughter's very badly scaled kettle - & it was clear in 5 minutes, as it said on the can. Brilliant product. Now home with no Robert Dyas within range, so the question now is whether I pay out for the delivery cost by buying it online.

  • 5 / 5Quality

    5 / 5Value

    14 June 2019


    works instantly, have used this many times, does a great job

  • 5 / 5Quality

    5 / 5Value

    05 June 2019

    So easy to use with great results!

    Having to use descaler so often here was a real chore. I picked up Kilrock Multi-Purpose Descaler on a whim and would never use anything else. It’s quick and easy to use with quite brilliant results.

  • 5 / 5Quality

    4 / 5Value

    27 May 2019

    Clean kettle!

    Brilliant de scaler... I use much less than recommend in just boiled water. I only leave in for a couple of minutes, rinse, boil again, rinse again then I have a scale free kettle for a couple of weeks. Bought on special deal so even better!

  • 5 / 5Quality

    5 / 5Value

    15 May 2019

    Easy Descaler

    I use this for our kettle and shower heads and haven’t found a product that works so quickly and easily.

  • 5 / 5Quality

    5 / 5Value

    14 May 2019

    First rate

    Excellent product and much cheaper than other products I have tried!

  • 5 / 5Quality

    5 / 5Value

    12 May 2019

    sparkling loos

    my loos are sparking clean and the price is fair. Am happy with my purchase.