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Discuss Calshot Inhibitor - Williams & Co. in the Product Reviews area at

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  1. Mike Jackson

    Mike Jackson Plumber GSR

    Well I used the Calshot Cleaner yesterday. It had been in the van for quite a few days so was nice and cold when I took it in. The calshot comes in a concertina type bottle that you squeeze to get the contents out. It is supplied with a threaded spigot and a plastic 1/2" FI connector. The spigot has a check valve fitted. The idea is to screw the connector onto the threaded spigot and then screw the whole thing onto the filling valve on the heating system. This was where I cam slightly unstuck, The filling point was pointing upwards under the boiler and there wasn't room to screw the calshot on. Not to be defeated I used a straight coupling to adapt the thread to 1/2 MI so that I could connect the bottle to the filling loop. It wasn't possible to connect the bottle straight to the filling loop as the end of the thread was flat.

    The instruction state that the pressure should be dropped on the system before the cleaner was injected but I decided to see if I could force the cleaner in with the system under pressure. No go, I had to lower the pressure so that I could squeeze the cleaner in. This is a distinct disadvantage over products like the fernox express range etc. which will go in under pressure although the calshot does retail at a lower price.

    When I stopped squeezing the container it started to refill from the heating system so I had to squeeze the cleaner back in and shut off the isolating valve quickly. This was a bit awkward as I had to use both hands to squeeze the container because I was connected to the filling loop rather than the rigid valve. The check valve is obviously not that effective.

    In all not a bad product, not as easy as the aerosol type products to inject into a system but does the trick at a lower price.

    In all honesty it's not something that I would look to buy myself as I have made an injection pump from a garden sprayer that enables me to inject the normal chemicals in under pressure without having to pay the premium price of an aerosol product.

    For someone that only uses CH chemicals very rarely it's not a bad product but for someone doing it on a regular basis it's a bit too much faffing about. Strikes me as more of a DIY product if I'm honest.
  2. Ray Stafford

    Ray Stafford Guest

    Re: Williams & Co product review thread

    Thanks Mike for such a detailed and thoughtful review. If thats the standard of reviewing that we can get on the forum, I have am sure that we can keep getting products to review from a range of manufacturers.

    Smashing job - thank you. :hurray:
    • Like Like x 1
  3. Dotty

    Dotty Guest

    Re: Williams & Co product review thread

    Calshot cleaner and inhibitor.

    Finally got the chance to use these on a domestic system this week. Unlike Mike J I had plenty of space to manoeuvre. The chemicals are fairly easy to dispense if, like me, you have bear paws. I can see how there would be a problem with the bottle back filling unles you're working through a non return valve as the bottle non return valve doesn't look to seal too well.

    The chemicals themselves are of a muchness. The delivery method is a nice idea but I think it.needs the nrv looking at.

    Would I buy it?

    I probably would as it is compact and fairly simple to use. The clincher for me with this over aerosols is the lack of a propellant. And the old hippie that dwells within me likes that.

    Thanks again Ray.
    • Like Like x 1
  4. Ray Stafford

    Ray Stafford Guest

    Re: Williams & Co product review thread

    Thanks Croppie. I will pass on the feedback regarding the NRV to the manufacturers.
  5. JCplumb

    JCplumb Plumber

    Re: Williams & Co product review thread - Calshot Inhibitor

    Had the chance to use one of the Calshots Ray provided last week but have been 'busy' so not posted a review until today.
    Added a radiator to my mums house last Friday, the heating system is only 3 years old and didn't need cleaning but I did drain it down with the intention of renewing the inhibitor.
    Hung and piped up the radiator, fitted everything except the blanking plug then screwed the Calshot in and squeezed. It was ridiculously easy to be fair.
    There's not really much more that can be said, if the system isn't under pressure these are ideal and come with everything you need, no mastik gun or funnel contraptions required.
    I have heard of issues where these are difficult to use when systems are pressurised but to be fair I'd usually release pressure and drain off a pint or so before adding inhibitor to a system, if a system needs inhibitor then I'd say it's a fair trade off to add a little oxygenated water in the process.
    Thanks Ray, I will be keeping a small stock of these as they are cheap enough and easy enough to use in the right circumstances. I also like the fact that they're a 1 shot deal and you just bin (recycle?) the container instead of having more than you need and ending up with half full tubs sloshing about.
  6. Ray Stafford

    Ray Stafford Guest

    Re: Williams & Co product review thread

    Thanks JCplumb. Glad it went well.

  7. kay-jay

    kay-jay Trusted Plumber GSR

    Re: Williams & Co product review thread

    Calshot inhibitor

    Finally got a chance to use this product at the weekend.
    Added via radiator vent. The so called nrv is a bit cheap as others have said. Wasn't really a problem fir me though as system was empty.

    Simply screwed bottle to rad vent and pushed the concertina bottle.
    All nice and easy customer even commented on what a great idea it was.

    I found it was easy to use and simpler than most other methods. There was no spillage either. My only criticism is that there is about 50ml left in the bottle which you can't get out without pouring it as if it was a normal bottle if inhibitor which of course defeats the object...

    All in all a decent enough product but if it came down to it would i spend the extra couple if quid on it???

    Possibly not.

    For me the biggest thing in this products favour is that a full dose us 500ml not a litre which means i can pour it all into a tf1.

    I would like to see a range if 500ml dose bottles available generally.
  8. Ray Stafford

    Ray Stafford Guest

    Re: Williams & Co product review thread

    Thanks Kay-Jay. Glad it went well. With our BOGOF offer, you don't even have to worry about your pocket either! :)
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