Too much Pressure with Grundros UPS15-58FC, 3-Speed Circulator Pump, 1/25 HP, 11

Reply

  #1  
Old 01-16-12, 07:25 PM
Member
Thread Starter
Join Date: Jan 2012
Location: United States
Posts: 4
Received 0 Votes on 0 Posts
Too much Pressure with Grundros UPS15-58FC, 3-Speed Circulator Pump, 1/25 HP, 11

I have this Grundros UPS15-58FC, 3-Speed Circulator pump running on a 1/2 inch 250 foot underfloor pex leg. The rest of the home is is circulated by a boiler pump in my 2000 sq/ft home with cast iron radiators in the rest of the house.

The Grundros pump just is on the pex leg but the return goes back to the main boiler system return. My problem is that after about 24 hours my 12 lbs system is up to the the system relief valve pressure of 30 lbs. and it is actively venting.

There is an old style large expansion tank on the system, I don't know what it is set at as I never had to pay any attention to it. Do I need another expansion tank in the leg somewhere?

My system is set up similar to Figure 2 on this page. http://media.wattswater.com/1915905.pdf But no flow check or check valve as there is a cv in the pump.

What can I do to stop the pressure build up?

Thanks
 
Sponsored Links
  #2  
Old 01-16-12, 07:34 PM
lawrosa's Avatar
Super Moderator
Join Date: Dec 2010
Location: Galivants Ferry SC USA
Posts: 18,026
Received 42 Votes on 37 Posts
Do a search on here, "Expansion tank". I know there are sevaral threads regarding draining your type tank and the proper steps to do so.


Not sure what pros are on tonight. I will look around for you.

Pics of your boiler from all angles will help also. We may see things you dont.

But from what you state, I would start with the expansion tank. It probably needs to be drained and the air cusion replaced for thermal expansion.

Mike NJ
 

Last edited by lawrosa; 01-16-12 at 07:51 PM.
  #3  
Old 01-16-12, 07:38 PM
Member
Join Date: Aug 2009
Location: USA
Posts: 4,947
Received 0 Votes on 0 Posts
It could be that your expansion tank is water logged. There needs to be a cushion of air in the tank. You need to drain the tank completely of water and then refill your system to a min of 12 psi when cold. This will give you the air cushion you need. Make sure you get all the water out though.

It could also be that the auto fill valve is slowly leaking water past its seal. If you have a tankless coil for domestic hot water, those can leak water from the domestic side into the boiler size raising the pressure.
 
  #4  
Old 01-16-12, 08:45 PM
rbeck's Avatar
Member
Join Date: Jul 2007
Posts: 2,466
Received 2 Votes on 2 Posts
  #5  
Old 01-17-12, 05:33 PM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 3 Votes on 2 Posts
Yes, do the expansion tank service, but...

To me this sounds suspiciously like what Droo said; the fill valve is leaking through...

My problem is that after about 24 hours my 12 lbs system is up to the the system relief valve pressure of 30 lbs. and it is actively venting.
 
  #6  
Old 01-17-12, 08:00 PM
Member
Thread Starter
Join Date: Jan 2012
Location: United States
Posts: 4
Received 0 Votes on 0 Posts
OK so I got home late and drained the expansion tank late last night when it was cold, just as directed with your helpful instructions. There was about 7 gallons of water that came out.

It is not too cold today in Buffalo so the heat just came on in the AM. The pressure was up around 20 when it was done bringing the temp up to daytime setting. I got home and since it was warm today and the house must have been up to temp for a while. The boiler was around 110 and the pressure was still around 20. I checked later and it had fallen to about 18 or 19. I hope when I return late tonight the pressure has fallen back to 12, crossing my fingers.

So I was wondering do I need and should I install any air vents in this system. It has not had any and I was wondering if I should, where to place them and what kind? Below are some photos of my system.

Boiler with expansion tank



New Grundros pump for pex leg


Mixing valve for pump and pex


Ultrafin that will be insulated


Thanks in advance.

Doug
 
  #7  
Old 01-17-12, 08:32 PM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 3 Votes on 2 Posts
Doug, you know that you need to heavily insulate below that floor tubing, right? You really don't want to radiate heat downward as well, you need all that heat going UP through the floor!

From what I can see, I don't think you have enough plates either...

I'm sure you realize that the yellow ball valve is a 'fast fill' and it's purpose is to bypass the pressure regulator for filling and purging, right?

That blue handle shut off valve appears to be weeping around the stem packing. Have you tried snugging down the gland nut on that valve to stop that crying?

I hope when I return late tonight the pressure has fallen back to 12, crossing my fingers.
If it hasn't ... and pressure is still outta control, let the boiler cool, readjust the pressure to 12 PSI and CLOSE THE BLUE HANDLE VALVE and observe the pressure for a day or two. If it's now under control, you need to service the fill valve.
 
  #8  
Old 01-17-12, 08:59 PM
Member
Thread Starter
Join Date: Jan 2012
Location: United States
Posts: 4
Received 0 Votes on 0 Posts
NJ Trooper

Yes I plan to insulate the space below the joists with celotex with aluminum on the top.

Good advice on the weeper I will tighten that. And as well closing the fill if the system is not back down to 12 when the system is cool.

Yes my father in law installed the bypass after we moved in. There were many radiators stuck in the closed position. That and room by room renovations have had me removing radiators and draining the system all too often.

Thanks again for your advice.

Doug
 
  #9  
Old 01-18-12, 09:27 PM
Member
Thread Starter
Join Date: Jan 2012
Location: United States
Posts: 4
Received 0 Votes on 0 Posts
So this morning I turned the blue shut off valve off (I did tighten the packing and it no longer weeps) as suggested. By the time I left the pressure was up to about 18. When I got home at 8PM. It was off and still pretty hot from heating in the evening. The pressure was back to normal at around 12.

I have left the blue valve in the off and will check again in the AM after the heating cycle. But just as you suggested it seems like the fill valve needs service. So, is needs service a nice way of saying replace? Is there actually a way to service this part?

Thanks again.

Doug
 
  #10  
Old 01-18-12, 10:01 PM
lawrosa's Avatar
Super Moderator
Join Date: Dec 2010
Location: Galivants Ferry SC USA
Posts: 18,026
Received 42 Votes on 37 Posts
Probably a rebuild kit for it but its gonna cost as much as a new fill valve.

Its good that I see a union there and threaded pipe. If your going to replace install a new fill valve and add a backflow preventer since you dont have one. Also to make room replave that valve with a ball valve.

It would be wise to add another valve on the boiler side too. This way you can shut them both off to sevice the fill valve in the future.



Mike NJ
 
Reply

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: