Good small pump for filthy condensate

Craig_8

I don't think any wet rotor circulator will hold up in this type of service. the debris will get into the bearings and grind them up. I think you need to find a way to get a 3 piece circulator on there.

chris_69

Good small pump for filthy condensate

This system is built as described in various articles of Dan's: it's a steam boiler, with a circulator that pumps condensate through a heat exchanger, which heats the water for an under-floor radiant system. It works beautifully.

The circulator pump that pumps the boiler condensate through the heat exchanger is a bronze Taco 008 cartridge pump. The cartridges only last about a year before they become gucked up with the fine rusty sediment that's always present in the condensate.

I believe the right thing for that filthy, corrosive water is a bronze 3-piece circulator. Problem is, the boiler room is tiny, like a swiss watch inside, and to make room for the 3-piece circulator, you'd need to re-plumb the whole thing, knock out a wall, and relocate the hot water heater. Ain't gonna happen.

Is there anything else that's about the same size as the Taco circulator that might last a little longer in service? Looks like the Grundfos stainless pumps, like UP25-58SF are of a different design... anybody know if they stand up better to muddy, corrosive water?

Weezbo

this is a good question..

*~/:) i am not sure thats the best plan of attack.

what i have at the moment is similar , my plan is to valve off the "Field side",... run it through my transfer pump with a Caleffi dircal and thin out the garbage left over after flushing the system..

it is my belief , though i cannot prove it, that the glycol loop that is hundreds of feet long ,..feeding the existing system and a radiant floor in stainless , that i flushed out and purged today,has a leak underground ..its 3 inch iron welded pipe and is bleeding heat through the ground at the moment ...this could be an insulation issue,.. though i tend to think 'its a leak'..i have a sample to send off buh first i must identify the glycol..

you are somewhat in similar straights.

if you have no means of identifying where its taking on mud,... cleaning it the way i am considering may not be altogether easy way for you to go .

sometimes in instances like yours , dropping the pipe to a flat with oversized pipe and a plugged valved take off and a short riser by street will allow a place to 'Catch particulates and by cranking open the valve, a way to flush the chubby pipe or clean it out ahead of the circ with some drill driven brush or in some cases a large screwdriver something that will clear the valve to allow the accumulation to exit the valve..

just a thought..hope it helps..

chris_69

Thanks, not quite the same situation

Thanks for the info. My situation isn't quite the same -- the radiant loop is completely clean - the water in it is probably seven or eight years old and looks entirely clear and drinkable. The mud is on the primary side -- and its there because the system is one pipe steam, open to the air, with 100 year old radiators.

chris_69

Bell & Gosset PL series???

I'm resurrecting this question because I'm sick of replacing the cartridges on the circulator.  Can't possibly fit a 3-piece circulator in there, but it looks like B&G makes a circulator, the PL series, that might work. Anybody know about it?  B&G describes it as a dry-rotor design whose "Advanced close-coupled design increases pump life and efficiency,

assures dependable seasonal start-ups and can easily handle difficult water conditions"

Charlie from wmass

It may work

Are you pumping away from the boiler off an upper tapping? are you using a wye strainer? Also are you using a bypass to limit water temperatures going into pump?

chris_69

2 out of 3?

Yes, no, and yes.



The stuff that gets into the pump and ruins the bearings isn't heavy sludge, it's very fine particles that are distributed all throughout the boiler water - they'd pass through any strainer I could imagine.

Charlie from wmass

Stick a magnet to the strainer

It would help it catch the rust. then blow it out. A strainer does on its own catch much finer particles than you would think. It acts as a wide part in the river where the sediment can drop out.