×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Faulty non return valve on pump

Faulty non return valve on pump

Faulty non return valve on pump

(OP)
Hi

I got 4 x Condenser water pumps in parallel....2 new and 2 old.... non return valves on each

Occasionally I loose condenser water flow through the chiller when running of the new pumps

I did notice water flow noise coming from the two old the condenser water pumps, when they were off off. It was a hissing noise as if there was flow. The fan on the motor was not turning as I thought it would if the non return was not functioning. Anyway I closed the discharge valves on each of the old pumps and the hissing sound immediately stopped.

My question is; can water run backwards through the pump with out the impeller necessarily rotating if the non return is not sitting right?

BQ

RE: Faulty non return valve on pump

Yes. The check valve is just not leaking back enough to spin the pump.

RE: Faulty non return valve on pump

Agree, The flow needs to be quite reasonable to overcome the static friction. A hissing sound implies quite low quantities. A gurgling sound would be higher flow.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Faulty non return valve on pump


Apart from the answers above (agree!) it is a separate question why the two old checkvalves are failing.

This could be caused by a multitude of reasons, one or several in combination. Two failing at the same time could indicate an imbalance in flow/capacity (layout or dimension), but not necessarily.

RE: Faulty non return valve on pump

Is this tied in with your previous posts about cavitation and other problems reported?

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

RE: Faulty non return valve on pump

(OP)
Artist
Yes. The non return valves passing is not the issue. The chiller cuts out on low condenser water flow every 24-48 hours approx. Head wrecing trying to find the reason

I arrive at the chiller. Valves on chiller n towers closed and pump off. Alarm on the chiller.
Could air be getting in ?
B

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members! Already a Member? Login


Resources


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close