Lunt O Ring Replacement.

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Lunt O Ring Replacement.


Post by CarlGreen »

Hi All (Admin, I was not sure where to post this so please feel free to move to more appropriate forum if its not suited to this one)

I needed to replace the O rings on m Lunt60 THa.
Bresser (UK) sent me replacement O rings (Charged 10 euros plus 6 euros delivery - which is fair enough I guess) However, They advertise 2 different sizes on their website (3 Actually but the one for the Lunt 50 states it is only for the 50) So I ordered one of each of the other sizes they offer for the 60 (Basically a 34mm and a 32mm) They arrived promptly, however, NEITHER fit my pressure tuner!

The largest one is too small compared to the one actually on my Tuner (I measured it and it is approximately 45mm diameter?) Also, I have 2 of them on my tuner (They sent one of each size.....thought they would sell them as a set of 2 if that's what is on the tuner so alarm bells rang as soon as packet was opened)

Has anyone else got a Tuner that takes (Double) O rings of this diameter? If so, do you know where I can get replacements?

Thought I would ask on here in an attempt to pre-empt any bad news from Lunt (Such as its so old they have discontinued the tuner spare parts are not available!

Thanks all.
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Re: Lunt O Ring Replacement.


Post by admin »


seems like as good a place as any for it...

I would have thought that O-rings are fairly much a commodity item, and there's probably no difference between those used for a pressure tuner than those used in some completely different application - the important things are the diameter across the O and the thickness of the ring. If you have a digital micrometer you should be able to measure both and then probably order matching (or close to matching) rings off of Ebay or similar. The price is likely to be dominated by the postage, so it may make sense to order a few variations of the size you think you need if the postage is combined.


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