Adapter for USA Garden Hose Thread

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Niel

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# 160247 29-Dec-2014 21:51

Some time ago there was a post (can;t find it now) about someone that fell into exactly the same trap as me, bought an Orbit irrigation timer from Amazon for much less than the local price just to discover in USA they use a special "Garden Hose Thread" for garden hoses. It is close to, but not the same as used by virtually every other country. To make it worse, the part number that Orbit uses for the product sold in the USA is exactly the same as in NZ. My temporary (now almost a year) solution is to use 2 washers to seal before the different pitch thread interferes.

I have tracked down an apparently suitable adapter that could be used for connecting 19mm polypipe. I have not bought it yet, but pretty sure this is it. GHT is approximately 26mm diameter, the size in the listing refers to the hose size and you can also get ones for 16mm or 12mm hoses.
http://www.ebay.co.uk/itm/400818114319

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Aredwood

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# 1205845 30-Dec-2014 02:21

I wouldn't waste any time with that. Since it is listed on Ebay UK, it would most likely be for UK pipe thread. And UK pipe thread happens to be exactly the same as NZ thread. What you want is a BSP to NPT adaptor. BSP = British standard pipe thread = thread type used in NZ, Aust, all of UK and Europe. (Sometimes called BSPT instead of BSP) NPT = National pipe thread = Thread used in USA and probably Canada.

As for the adaptors you need, 1 each of http://www.ebay.com/itm/Brass-Male-Female-NPT-BSP-Adaptor-/331405318178?pt=LH_DefaultDomain_3&var=&hash=item4d294bd822 and
http://www.ebay.com/itm/Brass-Male-Female-BSP-NPT-Adaptor-/231411509637?pt=LH_DefaultDomain_3&var=&hash=item35e1336985 You need the 3/4 inch size.

Niel

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# 1205856 30-Dec-2014 07:23

Nope, USA household indoor thread is NPT but outdoor garden thread is GHT or Garden Hose Thread. To complicate matters, it seems their irrigation systems are NPT as it is permanently plumbed in, just garden hoses (taps) are GHT. There are no thread cutters for it as it is tapered, so you can't even modify a BSP thread even though it is very close to the same.
Standards and connectors section: https://en.wikipedia.org/wiki/Garden_hose

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steve98

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# 1205887 30-Dec-2014 08:57

Niel: Some time ago there was a post (can;t find it now) about someone that fell into exactly the same trap as me, bought an Orbit irrigation timer from Amazon for much less than the local price just to discover in USA they use a special "Garden Hose Thread" for garden hoses. It is close to, but not the same as used by virtually every other country. To make it worse, the part number that Orbit uses for the product sold in the USA is exactly the same as in NZ. My temporary (now almost a year) solution is to use 2 washers to seal before the different pitch thread interferes.

I have tracked down an apparently suitable adapter that could be used for connecting 19mm polypipe. I have not bought it yet, but pretty sure this is it. GHT is approximately 26mm diameter, the size in the listing refers to the hose size and you can also get ones for 16mm or 12mm hoses.
http://www.ebay.co.uk/itm/400818114319

Hi Niel - that was my thread! Thanks so much for this, I might order some and see how I go. Your workaround of using two washers has worked pretty well for us so far but it would be nice to have it done 'properly'. I'll look into getting some shipped over and will let you know how I go. Thanks again.

Niel

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# 1205906 30-Dec-2014 09:13

Just to clarify, it is the garden tap timers that are GHT and the permanently installed irrigation systems that are NPT.

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RunningMan

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# 1205941 30-Dec-2014 10:24

For reference - original thread:

http://www.geekzone.co.nz/forums.asp?ForumId=141&TopicId=153734