As an essential retailer, our stores remain open across the UK

Sentinel Internal Leak Sealer 1Ltr (99730)

£ 15.99INC VAT

Add to basket for...

Sentinel Internal Leak Sealer 1Ltr (99730)

Internal Leak Sealer for small inaccessible leaks and weeping joints in all types of indirect heating systems including those containing aluminium components. Compatible with elastomers.

  • 1 Year Guarantee

More Info

View all: Sentinel Central Heating Leak Sealers

Bulk Save Save up to 10%
Bulk savings
QTY Price per item Saving
1 - 2 £15.99 (£15.99/Ltr) -
3 - 5 £15.19 (£15.19/Ltr) Save 5%
6 + £14.39 (£14.39/Ltr) Save 10%
£15.99INC VAT (£15.99/Ltr)

Add to basket for...

Sentinel Internal Leak Sealer 1Ltr is rated 4.6 out of 5 by 78.
  • y_2021, m_1, d_19, h_22
  • bvseo_bulk, prod_bvrr, vn_bulk_3.0.12
  • cp_1, bvpage1
  • co_hasreviews, tv_0, tr_78
  • loc_en_GB, sid_99730, prod, sort_[SortEntry(order=FEATURED, direction=DESCENDING), SortEntry(order=SUBMISSION_TIME, direction=DESCENDING)]
  • clientName_screwfix
  • bvseo_sdk, java_sdk, bvseo-4.0.0
  • CLOUD, getAggregateRating, 35ms
  • REVIEWS, PRODUCT

Add to saved list...

Save
Rated 4 out of 5 by from So far so good Used half bottle in a 5 radiator combi system. Been losing pressure for a while now.1 bar over a week. Filled via magnaclean body. Pressure been stable for a couple of days now. Collection was ready within minutes. Shop was empty. Good to see staff cleaning counters and floors in quiet periods.
Date published: 2021-01-15
Rated 5 out of 5 by from Good Job Done Stopped a joint leak instantly, very pleased. Good product.
Date published: 2021-01-13
Rated 1 out of 5 by from Waste of money I have a combo boiler with 10 radiators and had a small leak on a compression fitting , more like a small weep . Put 2 litre of this sealant in and it still leaks. Ran the system got for 24h and then another day as normal but it did not seal the small leak. Finally had to make access to the fitting a buy a special spanner. Better to save your money and buy a spanner . The spanner gives a better result and is cheaper. Don’t wast your time using this sealant.
Date published: 2021-01-10
Rated 5 out of 5 by from BIG LEAK UNDER CONCRETED FLOOR Customer had a huge leak from a pipe buried deep in concrete downstairs bathroom (old cole shed). Combi boiler would drop from 1.5 bar to zero pressure in less than 10 minutes so I knew it was a big leak. If I'm honest I didn't think a sealer would work, I thought it'd be up with the floor and put in new pipework which would been a huge job as the pipe runs about 10meters under concrete. Anyway, I put in 1/3 of the bottle in via the in-line magnetic filler, refilled, bleed, and ran the ch system.... 10 mins later pressure was still dropping but nowhere near the speed it was before. So I added 1/3 more to the system, 2/3s in total....BOOM! Fixed! Couldn't quite believe it but 12 hours later pressure hasn't dropped. I'm going to wait a week and put the remaining 1/3 in whether it drops or not. Let's see how it holds up long term but I can promise and vouch that it fixed a huge leak using just 2/3's
Date published: 2021-01-06
  • y_2021, m_1, d_19, h_22
  • bvseo_bulk, prod_bvrr, vn_bulk_3.0.12
  • cp_1, bvpage1
  • co_hasreviews, tv_0, tr_78
  • loc_en_GB, sid_99730, prod, sort_[SortEntry(order=FEATURED, direction=DESCENDING), SortEntry(order=SUBMISSION_TIME, direction=DESCENDING)]
  • clientName_screwfix
  • bvseo_sdk, java_sdk, bvseo-4.0.0
  • CLOUD, getReviews, 10ms
  • REVIEWS, PRODUCT

Can this leak sealer be used in a microbore system?

Asked by: Sherrif
Hello - Generally, you can use Sentinel Leak Sealer on any system (and pipework) but caution has to be exercised with microbore particularly if the system is not clean and potential for sludge to clog up. Kind Regards, Sentinel Customer Services
Answered by: Sentinel Product Help
Date published: 2021-01-13

Compatable with ALADDIN HV30C AUTOVENTS?

Is this solution compatible with self bleeding radiator vents such as 'ALADDIN HV30C AUTOVENTS' (34093)?
Asked by: 7heaven
Hello - These are autovents (air bleed) for radiators. If the Sentinel Leak Sealer was to get into the autovent and dried out (as water evaporates) it may clog it up and stop it from functioning. Kind Regards, Sentinel Customer Services
Answered by: Sentinel Product Help
Date published: 2020-12-16

Can I pour this directly in the radiator? If not. Which one can I pour directly in the radiator?

I do not want any sealant to use in the expansion tank. I would like to pour it in directly in the radiator. I believe should pour it in upper floor radiator and it will travel to other radiators etc
Asked by: Nazzy2020
Hello - 1 litre or 1 400ml aerosol of Sentinel Leak Sealer is sufficient to treat a typical domestic system of up to 10 radiators. Larger systems should be dosed with twice this amount. After dosing is complete, the system should be operated normally for at least 15 minutes as heat is beneficial to the sealing process. Open Systems: Dose via F&E cistern, via a by-pass feeder or use a Sentinel Dosing Vessel. Sealed Systems: If the system is empty, add to any convenient point before filling. If full, use a Sentinel Dosing Vessel to inject via the filling loop or other access point. Sentinel Customer Services
Answered by: Sentinel Product Help
Date published: 2020-12-15

Does this work with Fernox Hp-5c?

Hello there, I have an air source heat pump (water to water) central heating system with an annoying leak. The system is already dosed with Fernox HP-5c liquid, If I add Sentinel leak sealer would these two products be compatible?
Asked by: Anonymous
Hello, Sentinel products are compatible with other major brands' products. Kind regards, Sentinel Customer Services Team
Answered by: Sentinel Product Help
Date published: 2020-12-03

Will this work with fernox inhibitor's

Asked by: Emhmk1
Hello, Sentinel products are compatible with other major brands' products. Kind regards, Sentinel Customer Services Team
Answered by: Sentinel Product Help
Date published: 2020-12-03
  • y_2021, m_1, d_19, h_22CST
  • bvseo_bulk, prod_bvqa, vn_bulk_3.0.12
  • cp_1, bvpage1
  • co_hasquestionsanswers, tq_43
  • loc_en_GB, sid_99730, prod, sort_[SortEntry(order=LOCALE, direction=DESCENDING), SortEntry(order=FEATURED, direction=DESCENDING), SortEntry(order=SUBMISSION_TIME, direction=DESCENDING)]
  • clientName_screwfix
  • bvseo_sdk, java_sdk, bvseo-4.0.0
  • CLOUD, getReviews, 20ms
  • QUESTIONS, PRODUCT
  • bvseo-msg: BV SEO Content for this product did not include verbose reviews.;
Specification
Brand Sentinel
Manufacturer Guarantee 1 Year Guarantee
Pack Size 1
Pieces in Pack/Case 1
Product Type Internal Leak Sealer
Volume 1 Ltr

Downloads

Safety Data Sheet (COSHH)