Air in CH system and hot water returning to FE tank via the cold feed

[Ric2013]

You posted


I got it from one of your files above... "Selectric UPS Old Style" page 1 shows speed 1 curve starting at 3.75/3.76M ?.

Can you look at the chart on my file again and tell me what you see? I make it between 3.5 and 3.6 and would like to know if this is human or electronic error.
This is how it appears on my screen:

 

[doitmyself]

Can you look at the chart on my file again and tell me what you see? I make it between 3.5 and 3.6 and would like to know if this is human or electronic error.
This is how it appears on my screen:View attachment 36507

I have to agree with john.g. The speed 1 line crosses the y-axis at 3.75.

 

[John.g]

Can you look at the chart on my file again and tell me what you see? I make it between 3.5 and 3.6 and would like to know if this is human or electronic error.
This is how it appears on my screen:View attachment 36507

(Internet down for past few hours so couldn't relpy)

A bit confused as to why you ask human /electronic error as this I presume is a grundfos data sheet that you posted?, I just copied the data from it into my own spreadsheet, if you can post the proper chart I can incorporate that data in the spreadsheet and re post.

 

[Ric2013]

It's okay John. I'm not very good at reading data from a screen for some reason and I was reading the digits 3.5 against the 3.75 line.

So ignore my comments above.

 

[John.g]

It's okay John. I'm not very good at reading data from a screen for some reason and I was reading the digits 3.5 against the 3.75 line.

So ignore my comments above.

No problem, if you do come across any info on that 25-50 selectric with those power settings I would appreciate it. (#70)

 

[Ric2013]

Have you tried asking Grundfos? I think that's where I got the file for the VERY old Selectric pumps from. Rang them and asked for the curves IIRC.

 

[doitmyself]

Can you post any links (charts etc) to a UPS 25-50 Selectric, power outputs 40W, 65W & 95W. (installed in a new build house in 2005/2006), still running.
Thanks.

The curves are exactly the same as for the UPS 15-50 Selectric of the same vintage. The innards are the same, it's just the connections which are different.

 

[John.g]

The curves are exactly the same as for the UPS 15-50 Selectric of the same vintage. The innards are the same, it's just the connections which are different.

ref post#61
File "selectric UPS pumps old" shows the UPS 15-50 with power inputs of 35/45/50 watts. In "selectric very old" it shows the UPS 15-50 with power inputs of 40/65/100 watts with different speeds/curves, my query pump, a UPS 25-50 has power inputs of 40/65/95 so I will assume that the pump curves are similar to the latter one, above, its a 2005/2006 install. I wonder what was the time span period for the UPS 15-50 35/45/50 watts.

 

[doitmyself]

Here is the info you are looking for. The PC 9706 on pump data plate (see pic of the pump) shows that it was in production in 1997.

 

[John.g]

Here is the info you are looking for. The PC 9706 on pump data plate (see pic of the pump) shows that it was in production in 1997.

Thanks for that data.