stainless adaptor into pump

[e67]

I have a 1 and 1/4 male thread adapter with a 1 inch barb that screws into the top of a submersible pump. I noticed that it only screws easily into the Grundfos SQ 200
about 3-4 threads before it starts to bind. Seems a little tight to me considering that there are about 10 threads going into the pump. Anyone else had this situation with the SQ 200? And did you use teflon tape on these threads? And how tight should I go on this connection?

 

[ThaiTaffy]

I have a 1 and 1/4 male thread adapter with a 1 inch barb that screws into the top of a submersible pump. I noticed that it only screws easily into the Grundfos SQ 200
about 3-4 threads before it starts to bind. Seems a little tight to me considering that there are about 10 threads going into the pump. Anyone else had this situation with the SQ 200? And did you use teflon tape on these threads? And how tight should I go on this connection?

Could be a different thread pitch could be a tapered thread, typically I use tru-blu liquid PTFE on any non drinking water applications aswell as a small amount of PTFE tape this lubricates the thread some making the initial tightening easier. Check the data sheet for a specification on thread the Europeans love to use weird metric threads that almost fit similar imperial fittings.

 

[wpns]

Could this be the difference between NPT (tapered) abd BSP (straight) threads?

 

[ThaiTaffy]

Could this be the difference between NPT (tapered) abd BSP (straight) threads?

That's what I would think.

 

[wpns]

Europeans love to use weird metric threads that almost fit similar imperial fittings.

I won't point out that BSP is a British standard. Also, "G" threads, the bane of my existence, almost NPT but not quite, where the adapter can cost more than the thing you are connecting.

 

[ThaiTaffy]

I won't point out that BSP is a British standard. Also, "G" threads, the bane of my existence, almost NPT but not quite, where the adapter can cost more than the thing you are connecting.

Of course its British we pretty much invented everything.

 

[wpns]

Yeah, I'm looking for an RS485 (*) pressure sensor but it's available in either G1/4 or M20-1.5, and the adapters (is G1/4 the same as BSP 1/4?) are confusing and expensive, and getting it wrong is way too easy.

(*) Just to keep it topical for DIYsolar.

 

[ThaiTaffy]

Yep g1/4 is the same as bspp

 

[e67]

so in general at least in the USA its ok to use teflon on the threads??

 

[ThaiTaffy]

so in general at least in the USA its ok to use teflon on the threads??

Can't see any reason not too just bare in mind tapered threads use whatever you want but straight threads leave the first 1 or two threads then go ham then add more if not using an additional thread compound.

 

[outboard1196]

I have a 1 and 1/4 male thread adapter with a 1 inch barb that screws into the top of a submersible pump. I noticed that it only screws easily into the Grundfos SQ 200
about 3-4 threads before it starts to bind. Seems a little tight to me considering that there are about 10 threads going into the pump. Anyone else had this situation with the SQ 200? And did you use teflon tape on these threads? And how tight should I go on this connection?

Where did you get the fitting from ?

 

[e67]

Aqua Science online...btw another question... about the Grundfos SQ 200 ,a very common pump nowadays...would you wire that 2 wire with 12/2 or 10/2 Romex?? What has been your experience with it regarding start up and run ....?100 ft well and 200 ft total to pressure tank...

 

[outboard1196]

Aqua Science online...btw another question... about the Grundfos SQ 200 ,a very common pump nowadays...would you wire that 2 wire with 12/2 or 10/2 Romex?? What has been your experience with it regarding start up and run ....?100 ft well and 200 ft total to pressure tank...

Hmmm I ordered fittings from them too and they didn't screw in correct like the thread was cut too big .
For in the well casing you need Submersible pump wire . me personally I used dual rated thhn / thwn wire .
What's the full number of the pump ? The book should have wire specs called out for length.
I have an sq5 and see around 1000w .