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"Absolutely outstanding service. These folks really do know how to do an amazing job. I honestly am so delighted with everything they have done. The kit is superb, water tastes wonderful. They always send the filters quickly and have answered many questions I had when fitting the system and the replacement filters. I highly recommend them. Such lovely staff, always so helpful and easy to contact when you need advice. So very glad I went with them and so grateful to them for such a high quality service. 🤩 great work 🤩"
Kelly - June 2025
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Product Description
Bristan Boiling Tap Compatible Replacement Water Filter
Perfect compatible replacement water filter for your Bristan Hot Tap
Replaces GLL RAPSNK4 SF C and GLL RAPSNK3 C water filters
Protects your Bristan from limescale build up
Excellent taste and odour reduction
You get everything you need to swap over
British made using only top quality materials
Replace every 6 months*
Full Money Back Guarantee if not totally satisfied
Can be Stored for Years (IF never used / wet)
Brand New, Unopened and in the Original Packaging
How Long Does it last For?
*This filter should Last for 6 months in 95% of UK Water Areas
Dependent on your local water chemistry.
It can be hard for us to be completely sure that this filter will stop limescale for the entire 6 months - due to there being thousands of local water treatment plants in the UK, each with it's own a unique water chemistry - which can change regularly.(Even within the same area and postcode the water source can be different).
However, please rest assured that the cartridges do work well for the full 6 months for at least 95% of our customers.
You will know the filter's worn out when the limescale indicator on your Bristan changes (if you have one)... or ifyou see "film" on your tea and coffee... or you start tasting chlorine... or it's past 6 months - whichever is the sooner.
If you're in a particularly bad scale area the flow rate can make a big difference to how long the anti-scale element of your filter lasts. The slower the better.
We'll send you a free flow rate regulator / shut off valve to alllow you to adjust the flow rate of water through the filter into the tank.
How to Swap this New Filter with Your Bristan Original?
It's easy!
You simply swap out the old Bristan filter cartridge with our new one.
All you need to do is remove the in/out tubes and insert them into your new compatible cartridge.
Apart from that simply follow the original change instructions eg turning off the power supply and flushing the filter through etc.
(We send full instructions too!)
This customer had this to say about their Bristan compatible replacement filter: "Great service, filters arrived promptly, well packaged and I had it fitted within a few minutes. Almost half the orice of the one promoted bristan. Very happy. Well done"Richard Dunn
Check out this quick video sent in by a happy customer!
This shows an installation for a Proboil - but it's the same principle!
Free Tube Adapters?
Your original Bristan cartridge might have 3/8 tubing (9.6mm).
Like most water filters ours are 1/4 inch.
But don't worry. We include a free tube adapter in your kit in case you need them.
It takes seconds to setup. And you only need them once.
The filtration material inside both filters is basically the same.
And we'll send you a free Mounting Bracket to fit your new filter.
Not in a Hard Water Area?
If you are not in a hard water / limescale area then save yourself money by getting this standard inline filter.
However if you are in a very hard water area and want to better protect your hot tap / water tank then consider this more powerfulanti-scale filter.
It will also connect to your existing Bristan tank - but, if you choose that option, ask us for the free tube adapters (form 3/8th to our standard 1/4 inch tubing).
Does it Void Your Warranty?
Bristan and other boiling tap companies might say they will only warrant the original filter type supplied and claim it is "formulated specifically for their product"
... and that If you change it for an alternative filter it may have a "detrimental effect" to the system so will invalidate your warranty.
Well you do need an anti scale filter to prevent scale build up in your boiler (like you would for a kettle).
So, as far as that's concerned, any attempts to get you to keep using their filter would be fair enough.
But claiming a different filter will damage the unit is arguably like saying that using a different lightbulb to the one supplied will damage the light.
How can we put this any more politely?
Conclusion: The filter will NOT damage your boiling tap. But the manufacturer might use it as a reason to void your warranty.
Don't worry!
Although many customers have bought these alternatives and are perfectly happy with them, please don't worry. It's all on a Full Money Back Guarantee basis.
If you don't like it for any reason you can send it back!
Will it Affect Your Scale Reading?
No it won't affect your scale monitor / read-out. This will work in the same way as before.
Will it Affect Your Filter Warning Light?
It shouldn't do! That light is almost certainly set on a simple timer.
Just reset the light in the usual way.
Free Wall Mounting Clip
We'll include a wall mounting clip with your order - for free.
You can use this to mount the filter neatly in your cupboard.
You'll only need to fit thisonce - they're easy and convenient.
(The clip is optional. Simply add it from the screen pop up at the checkout stage.)
Bristan Boiling Tap Compatible Replacement Water Filter
Perfect compatible replacement water filter for your Bristan Hot Tap
Replaces GLL RAPSNK4 SF C and GLL RAPSNK3 C water filters
Protects your Bristan from limescale build up
Excellent taste and odour reduction
You get everything you need to swap over
British made using only top quality materials
Replace every 6 months*
Full Money Back Guarantee if not totally satisfied
Can be Stored for Years (IF never used / wet)
Brand New, Unopened and in the Original Packaging
How Long Does it last For?
*This filter should Last for 6 months in 95% of UK Water Areas
Dependent on your local water chemistry.
It can be hard for us to be completely sure that this filter will stop limescale for the entire 6 months - due to there being thousands of local water treatment plants in the UK, each with it's own a unique water chemistry - which can change regularly.(Even within the same area and postcode the water source can be different).
However, please rest assured that the cartridges do work well for the full 6 months for at least 95% of our customers.
You will know the filter's worn out when the limescale indicator on your Bristan changes (if you have one)... or ifyou see "film" on your tea and coffee... or you start tasting chlorine... or it's past 6 months - whichever is the sooner.
If you're in a particularly bad scale area the flow rate can make a big difference to how long the anti-scale element of your filter lasts. The slower the better.
We'll send you a free flow rate regulator / shut off valve to alllow you to adjust the flow rate of water through the filter into the tank.
How to Swap this New Filter with Your Bristan Original?
It's easy!
You simply swap out the old Bristan filter cartridge with our new one.
All you need to do is remove the in/out tubes and insert them into your new compatible cartridge.
Apart from that simply follow the original change instructions eg turning off the power supply and flushing the filter through etc.
(We send full instructions too!)
This customer had this to say about their Bristan compatible replacement filter: "Great service, filters arrived promptly, well packaged and I had it fitted within a few minutes. Almost half the orice of the one promoted bristan. Very happy. Well done"Richard Dunn
Check out this quick video sent in by a happy customer!
This shows an installation for a Proboil - but it's the same principle!
Free Tube Adapters?
Your original Bristan cartridge might have 3/8 tubing (9.6mm).
Like most water filters ours are 1/4 inch.
But don't worry. We include a free tube adapter in your kit in case you need them.
It takes seconds to setup. And you only need them once.
The filtration material inside both filters is basically the same.
And we'll send you a free Mounting Bracket to fit your new filter.
Not in a Hard Water Area?
If you are not in a hard water / limescale area then save yourself money by getting this standard inline filter.
However if you are in a very hard water area and want to better protect your hot tap / water tank then consider this more powerfulanti-scale filter.
It will also connect to your existing Bristan tank - but, if you choose that option, ask us for the free tube adapters (form 3/8th to our standard 1/4 inch tubing).
Does it Void Your Warranty?
Bristan and other boiling tap companies might say they will only warrant the original filter type supplied and claim it is "formulated specifically for their product"
... and that If you change it for an alternative filter it may have a "detrimental effect" to the system so will invalidate your warranty.
Well you do need an anti scale filter to prevent scale build up in your boiler (like you would for a kettle).
So, as far as that's concerned, any attempts to get you to keep using their filter would be fair enough.
But claiming a different filter will damage the unit is arguably like saying that using a different lightbulb to the one supplied will damage the light.
How can we put this any more politely?
Conclusion: The filter will NOT damage your boiling tap. But the manufacturer might use it as a reason to void your warranty.
Don't worry!
Although many customers have bought these alternatives and are perfectly happy with them, please don't worry. It's all on a Full Money Back Guarantee basis.
If you don't like it for any reason you can send it back!
Will it Affect Your Scale Reading?
No it won't affect your scale monitor / read-out. This will work in the same way as before.
Will it Affect Your Filter Warning Light?
It shouldn't do! That light is almost certainly set on a simple timer.
Just reset the light in the usual way.
Free Wall Mounting Clip
We'll include a wall mounting clip with your order - for free.
You can use this to mount the filter neatly in your cupboard.
You'll only need to fit thisonce - they're easy and convenient.
(The clip is optional. Simply add it from the screen pop up at the checkout stage.)
... and our Money Back Guarantee should help reassure you that we are an honest firm who will give you a first class, long term service.
How to get help
Call our help line on 020 8761 6611 at any time during UK office hours ie 9 am to 6 pm
Or email us for a rapid response.
Our policy is always to get back to you within an hour - or one working day at most.
Returns
In addition to your 3 Year Warranty, if for any reason you change your mind about your purchase within 90 days of receiving the goods, you can return your product for a full and complete refund *
PLUS we will pay for your return postage(UK only)
*This applies to individuals/ consumers using the products in domestic settings. Businesses please see our terms and conditions
Delivery Times
Order before 3 pm on any working day and we guarantee your order will be sent out the same day (not on weekends)
(To be honest we often manage to send them even after 3pm. But we can't promise that).
All prices on the website include delivery charges and VAT except where stated otherwise.
Delivery Charges
Your Standard "Free Delivery Included" is Second Class
This usually takes between 3 to 5 working days ie does not count weekends or Bank Holidays
Pay Extra for First Class
You also have the option at checkout to pay extra for First Class.
This should result in next day working delivery to mainland UK.
BUT please note while 95% do arrive next day this is not guaranteed.
However arrival within two working days is almost certain.
You can see your delivery costs at the checkout stage before you buy.
We are a family run business who value our customers. We've been trading for over twenty five years. So we won't be "here today gone tomorrow". Your Money Back Guarantees and Warranties will be safe.
Fully Accredited
Members of Safebuy the leading Consumer Assurance Scheme for online retailers approved under the Trading Standards Institute's Consumer Codes Approval Scheme.
Repeat Customers
Many of our clients have been buying filters from us for several years. Over 95% keep coming back to renew their filter because we offer a friendly, helpful service and great value prices. Checkout our TrustPilot reviews.
We’re Trustworthy
We have a huge number of great independent testimonials. For example on the Approved Consumer Code Directory for the Trading Standards Institute and on Google Certified Shops.
Such an improvement over unfiltered water. Losing microplastics, scale, chlorine and all the other nasties that can work their way in is just a bit of piece of mind for me in relation to my kids.
– Nick Love
I've had the filter installed for 1 month now and the water tastes loads better and no more smell of chemicals, just clean fresh filtered water I'd say it's the best water I've ever had.
– Neil Bradfield
“My filter fits easy and I am happy. We weigh the old filter when it is removed, filled with gunge which never got into our bodies with this filter. It’s quite frightening. My filter is worth every penny!
– Kathleen Gibson
Such an improvement over unfiltered water. Losing microplastics, scale, chlorine and all the other nasties that can work their way in is just a bit of piece of mind for me in relation to my kids.
– Nick Love
I've had the filter installed for 1 month now and the water tastes loads better and no more smell of chemicals, just clean fresh filtered water I'd say it's the best water I've ever had.
– Neil Bradfield
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