On a condensate pump, and a "Y" strainer....

04090

This photo shows the condensate tank on a Burnham V907 steam boiler installed in 1997.



Is there a problem with the way this condensate pump is set up? It appears in the manual that there's supposed to be a section of straight pipe where there's a elbow at the outlet, but I'm not sure I'm interpreting it right.



The pump was replaced with a new one 16 months ago because it was really loud. It's got the same problem again - sounds like a diesel truck engine.



The gate valve in the photo has the line limited to 25PSI just before the check valve. I assume our only option is having the pump rebuilt; is there anything we should try before then?



The "Y" strainer shown in the photo has been impossible to open for cleaning, it's never been done. Any advice on how to free it?

Jamie Hall

not an expert on condensate pumps...

by any means.  However, that said, a pump which is noisy (diesel truck, gravel rattling around, whatever) is almost certainly cavitating -- which will only get worse.  A pump will not cavitate if the net positive suction pressure is high enough; there are a number of reasons why it might not be in that setup, but the elbow on the outlet isn't one of them.  Hot condensate, however, might well be.



On the Y strainer.  It's a little hard to tell, but it looks like it has a blowdown connection on it?  That should take care of cleaning it, unless it is really badly gooped.  Assuming that is that there is a source of water to back flush it through the blowdown.



I'm not happy with the gate valve limiting the line to 25 psi.  How, exactly, does it do that?  First off, a gate valve should never be used for throttling -- just full open or full closed.  Second, a valve with a set opening cannot function as a pressure limiter; rather, it will have a pressure drop proportional to flow.  If you want a pressure limiter, you should be using a pressure reducing valve there, made for the purpose.

04090

poster response

The gate valve was closed until the gauge, also shown in the photo, read 25 while the pump was on.



It's been consistently reading 25 when the pump is running and it runs for 2-4 seconds every 5 minutes or so when the low water cutoff calls for additional water. It's set up such that when the pump is on, the burner shuts off.



Water that's been drained from the "y" strainer has always been on the clean side, about two cups come out. Does that nix the need for removing and cleaning the strainer?

04090

update

What kind of a pressure reducing valve should this have, or is what's on there actually OK?



Looked into it some, and only see a design that maintains pressure on the other side of the valve, that is, it'd maintain pressure on the boiler side; not the pump side.

Jamie Hall

Ah...

I think I see what you are doing: you are using that gate valve to maintain a particular back pressure on the pump?  Ah so... in that case, you are probably better off replacing the gate with a plain vanilla globe valve, and adjusting it -- as you have the globe valve -- to get the back pressure you want to make the pump run properly.  Might as well wait on that until the gate valve dies, though.



My apologies for misunderstanding how the setup was meant to work.



However, all that being so, does the noise of the pump change as you change the back pressure on it?  You might find that restricting the flow more (which you might not be able to do with the gate valve) might quiet the thing down.  Worth a try.

04090

Update on status...

When the valve is open all the way, the pressure gauge reads 15. By closing the valve I can, obviously, increase the pressure. The sound the pump makes does not change. The setting was at 25 PSI, and that's where I've left it.



I don't know if the Y strainer is cleaned if that'd help keep pump noise down or if it's essential to be cleaned regardless, or if removing the muck from the condensate pump would help..



Something is amiss in this system that's causing the pump to be incredibly noisy. Help finding it appreciated.



We're installing a rebuilt one and would like to avoid the problem from recurring.

nicholas bonham-carter

the quietest pump

one way to quiet it would be to remove it completely. can you repipe for a gravity return? with proper low pressure, the condensate should have no problem in getting back to the boiler.--nbc

Charlie from wmass

Why do you need a pump?

Can you take a photo back further?

04090

update

Would be happy to post some more photos on Monday night; that's the next time I'll be there.

Oak Park Electric

More info needed

Yes, definitely post more pictures.  The more the better. That looks like a lot of piping in that area behind the boiler, we need to be able to see where it goes.  Also, what does this system heat? Is it residential with radiators, or something different?  Does the pump ever leak, or is it just loud?

04090

update

I'll have to try again at taking some photos...



Had the pump rebuilt and the top bearing on the motor had broken down so much that it was making a groove in the outer case (also the top). The shop did a great job fixing it, and the pump is working as it should now.



To answer your questions, the line from the pump travels directly in 3/4" copper to the return pipe entering the bottom of the boiler. It's servicing an apartment building, three stories with 28 average size single pipe steam radiators.



Pump pressure is set to 25, no throttling necessary as the valve in the above photo is wide open. I assume that's right... it is what it's been.



All in all this seemingly overwhelming task was an easy fix, and with the help of a very competent motor/pump shop doing work while we waited two hours made it all the more worthwhile.



Still not sure about cleaning out that "Y" trap. It's been many years and the fitting to remove the strainer is all but stuck. Is it something that needs to be done?



This link might lead to a clearer photo:



http://i52.tinypic.com/30clwz7.jpg



Thanks.