Circulation Pump & Dirty Water

[xroad]

12 years ago, my mother hired some fly by night plumber to hack in a circulation pump to get the boiler's hot water to a hot water base board radiator in a cold part of the basement.

The pump pumps the water up about 6 feet and across the ceiling and back down to the radiator. The return water goes up to the ceiling height and back down and goes back into the boiler.

As ugly as the workmanship is, the setup works, sort of. Problem is that I am going through pump failures like there is no tomorrow. So far, 4 pumps in 12 years. They lasted 4 years, 3 years, 3 years, and the last one failed after 2 years.

The pump is a Taco 007-F5. FAQ at some web site on Taco pump said that oxygenated water, or water with lots of rust and sediments, will wear out or clog up the pump. OK, that explains it, as the boiler is a steam heat boiler. All steam heat water is brown.

I cannot change the boiler. I don't want to tap into a single pipe steam heat system that depends on gravity ... it is a basement room. SO, what now? Do they have pumps that tolerates "dirty water"?

 

[RPH]

Trash pumps - they can tolerate solids. Not for your use though! Do you have a strainer in the system?

 

[xroad]

Trash pumps - they can tolerate solids. Not for your use though! Do you have a strainer in the system?

No strainers in steam heat boilers. The pump picks up the water not at the bottom of the boiler. Probably at 6-12 inches above the bottom. So any chunks of rust flakes would sink below the water pick up point. The water is dark brown most of the time. It gets flush about 1x or 2x per month but generally, if the boiler sits for a few hours and not get stirred up, the first quart of water coming out is always black, typical of steam heat boilers.

 

[Ron Lombardo]

You need to change the pump again because a Taco 007 has a plastic impeller ... you need to find a pump with a Cast Iron Impeller ... 0010 ? maybe or series 100 B&G.

But you need to flush the steam boiler out ... they make a product called SQUICK .. dump a 1/2 of the container in run it for a day and then you need to flush the boiler out a few times. this will help you get the water to run clear in the site glass.

Ron

 

[xroad]

You need to change the pump again because a Taco 007 has a plastic impeller ... you need to find a pump with a Cast Iron Impeller ... 0010 ? maybe or series 100 B&G.

But you need to flush the steam boiler out ... they make a product called SQUICK .. dump a 1/2 of the container in run it for a day and then you need to flush the boiler out a few times. this will help you get the water to run clear in the site glass.

Ron

Hi Ron,

Thanks for the reply. I thought the Taco 007 spec of 40*-240*F would be suffice for the 212*F boiling point of water. 240* should be enough margin, right? I looked at the old failed Taco pumps that I did not throw away and the impeller looked OK. I think the failure is some where else in the pump. I am guessing the crusty dirty water is the biggest culprit but I cannot be sure. The old impeller body that spins in the cast iron housing is for sure well coated with rust.

I used boiler flush in the boiler in MY house. I was not impressed with it as the water goes back to it's old self after a few days. Performance did not improved any either. Now I just let the system rest for a few hours and open the drain valve to let out the dirty water that settled at the bottom of the boiler. I doubt the flushing agent will eliminate the pump failure problem.

I welcome any more ideas. I am at a total lost on this issue.

 

[Ron Lombardo]

Put a larger pump with more head pressure ... look at the TACO pump curve on their site ... pump it up a bit ..mayeb the pump is working too hard and its wearing out due to the head pressure and temperature of the water ?



Ron

 

[RossABQ]

A strainer ahead of the pump is a great idea, one with a fine screen. Blow it down regularly.

 

[antolod]

What failed on the pump? From the tech sheet, it looks like you can buy a new cartridge for one and have a 'new' pump. You might have longer life with an in-line pump such as the Taco 110 series, where the motor is not subjected to the circulating dirt in the water.

 

[xroad]

What failed on the pump? From the tech sheet, it looks like you can buy a new cartridge for one and have a 'new' pump. You might have longer life with an in-line pump such as the Taco 110 series, where the motor is not subjected to the circulating dirt in the water.

I bought the pump from www.pexsupply.com. It is about $70 total with shipping. The replacement cartridge is about $55-60 with shipping. Since I am not positive what part of the pump failed, I decided to get the new pump for just $10-15 more.

Is there a common component that fails in these pumps?

Not sure what "in-line" pump is. Please explain. My current pump, Taco 007-F5. It is mounted "in-line" horizontally hanging by the pipe. Is that what "in-line" mean?

Taco have lots of pumps. I cannot figure out why some of their pump cost $250 and some cost $65. All within the cast iron models. Spec looks similar sometimes. Did not look like high HP is higher cost. Did not look like high GPM means high cost either.

 

[rburke65]

You could call www.pexsupply.com..........I'm sure they have a number....ask what the diff. is between the $65 and the $250! Maybe they have a suggestion for you.

 

[xroad]

Spoke with a tech support guy at Pex Supply. Very helpful. Looks like the problem is the crappy water eventually clogging up the impeller. I asked about the high temp and he said high temp is not the issue. If it was, the seals would be leaking. Cast iron body also rust. So he recommends bronze ($$$$$) or stainless steel ($$$$$). In my case, the impeller clog will kill the pump before the pump body rust. Recommends a strainer before the pump, like RossABQ had mentioned.

In the end, flushing, straining, and bronze body will delay the failure.

 

[xroad]

Can I Blow Warm Air From The Boiler Room

The partitioned boiler side of the basement is quite warm.
The walled-off "nice" side is cold and need that baseboard radiator.

Can I open up a vent near the top of the wall and put in a fan and blow the warm air from one side to the other?

Are there concerns of carbon monoxide? Of course, there is! The boiler side have a window slightly open for fresh air. The "living room" "nice" side have a very leaky window for fresh air. I am reluctant to correct the leaky window situation as that is the only source of fresh air. The air from the two sides really don't mix. As I enter the basement, I go one way down a hall way to get to the boiler side and the other way down the hall way to the "living room" side. Each side have one window only.

 

[xroad]

Can I Blow Warm Air From The Boiler Room

Did some more digging around .....

If the boiler room is really small, isn't it required to open up a vent in the room to let air in from outside the boiler room (the "living room" side)?

 

[antolod]

Your 007-F5 pump is a wet rotor pump, with system fluid surrounding the entire rotating part of the motor. The Taco In-line pump has the motor complete separate. You can see a picture on their page here. My guess is that the clearances between a wet rotor and the housing is quite small, with very little tolerance for grit. The impeller is not the problem, but the rotor.

I'm certain the 110 series pump would be considerably more money, even in cast iron if you are getting the 7-F5 for only 70 bucks, and adding a strainer is probably your most economical solution.

 

[xroad]

Your 007-F5 pump is a wet rotor pump, with system fluid surrounding the entire rotating part of the motor. The Taco In-line pump has the motor complete separate. You can see a picture on their page here. My guess is that the clearances between a wet rotor and the housing is quite small, with very little tolerance for grit. The impeller is not the problem, but the rotor.

I'm certain the 110 series pump would be considerably more money, even in cast iron if you are getting the 7-F5 for only 70 bucks, and adding a strainer is probably your most economical solution.

antolod, thanks.

I have to look at the rust level of the cast iron. For the replacement Taco-110, I have to decide on cast iron or bronze. From pexsupply.com , $266 for the cast iron and $496 for the bronze. Any thoughts on cast vs. bronze?

 

[xroad]

Anyone know what is the purpose of the capacitor? In the electrical box of the pump, there is a 0.15uF (I think) capacitor.

 

[antolod]

Since your heating system is steam/very hot water, bronze is probably what most experts would recommend.

My bet is that with a strainer and keeping it cleaned (might be monthly, weekly or only once per season) you will get pretty good life with the $70 pump, as long as the failure is being caused by debris in the water rather than electrical failure of the motor or corrosion. Take one of the old pumps apart and look at the bore where the rotor cartridge is inserted. That should tell you how well the motor housing is holding up. If that area is badly corroded and rusted, a bronze 007-F5 might be a better choice and less expensive than an in-line. If that area is "clean" then the strainer will make a big difference.

 

[xroad]

Can The Pump Be Mounted In Any Orientation?

I open up the two old failed Taco 007 I have in the basement. The rotor feels very gritty, if it is oriented impeller pointing up with motor hanging down. It is gritty enough to make the pump stuck I assume. If I swing the motor upward, with the rotor impeller pointing downward, the gritty feel goes away, maybe even allow the pump to work.

Can the pump he mounted in any orientation?

I did not try to power it up yet ..... will try that soon.

 

[antolod]

From the Taco FAQ:

When we speak of mounting, we are referring to the motor or motor shaft part of the pump. This motor part should be in a horizontal position (parallel with the floor), with the capacitor box on top or either side but never under the motor. You can mount the motor in a vertical position ( with the end of the motor facing up to the ceiling), as long as you have more than 20 psi in your system.

I would try a horizontal mounting. According to this sheet (pdf) your "motor down" mounting is not recommended and flipping it up only if system pressure is over 20 PSI. The improper mounting might be the reason you've had several failures in the last 10 years.

 

[duaneb9729]

In my 32 years of being a furnace and a/c and boiler repair person, i have never seen a pump on a single pipe steam system.

Single pipe steam systems use one pipe to deliver steam and to return condensate to the boiler. The starts to flow with a vent on each radiator that closes as it gets warm, so the radiator would have to be mounted higher than the boiler.

If its not a steam boiler, as Antolod has mentioned your pump is mounted wrong.

Please dont install a screen our company has many pumps out there without screens and they will work years in a home style enviroment. Taco makes a great pump and the 007 is one of the best residential pumps out there.

We have 22 or 23 years of data to back that up. As with most things no manufacturer can overcome a stupid installer. Seems like the older i get the more i read the instructions because i am almost sure i have done something dumb before! <smile>

 

[xroad]

In my 32 years of being a furnace and a/c and boiler repair person, i have never seen a pump on a single pipe steam system.

No the pump have nothing to do with steam heat other than taking the hot water from the boiler that supply the steam heat and pump it to a hot water base board radiator. Like I said in the original post, some fly by night plumber hack this together 12 years ago.

I would have done it differently. I would take the hot water from the domestic hot water heater instead.

 

[xroad]

From the Taco FAQ:

From the Taco FAQ:
Quote:
When we speak of mounting, we are referring to the motor or motor shaft part of the pump. This motor part should be in a horizontal position (parallel with the floor), with the capacitor box on top or either side but never under the motor. You can mount the motor in a vertical position ( with the end of the motor facing up to the ceiling), as long as you have more than 20 psi in your system.

I would try a horizontal mounting. According to this sheet (pdf) your "motor down" mounting is not recommended and flipping it up only if system pressure is over 20 PSI. The improper mounting might be the reason you've had several failures in the last 10 years.

Ah-Ha, another data point! Thanks. With the Taco, my only option was mounting the pump with the rotating shaft vertical. That was the way the fittings and mounting flange installed. That certainly contribute to the short life.

I confirmed another nail in coffin. My father was a bit of an OCD and he flush that boiler VERY OFTEN. Steam heat system can take lots of neglect. I flush the steam heat boiler at my house every 2 months, if I remember. My father had moved on into a nursing home last year. Bingo, no one there to flush the system. When I remove the old pump, lots of rusty sludge. The first couple of Taco pumps lasted quite a few years.

Yet another possible reason for the short life of the pump..... The pump was not running in the summer. That allows the sediments to collect at the input and output of the pump. Had I kept the pump running, even in the summer, it may have been OK, you think?

Replaced the old Taco pump with a B&G (not sure what model) I had took out a few years back. The old B&G was leaking and not clog when I took it out. I took it apart and it looks like it need a new o-ring. Did not have tome to find a new o-ring and put it back together anyway. I just tighten the 4 bolts to the pump body a bit more. This pump worked fine. The design is a bit different than the Taco. The motor is not a "wet" motor. The impeller wet portion is separate from the "dry" motor". AND, it fit into the existing flange with the motor orientated correctly, with the oils hole facing up, like it should be.

This summer, I have to look into adding a shut off valve so I don't have to drain the boiler to change the pump. Also need to add a strainer. Tight space .......

Thanks ALL for your inputs. I have learned a lot from you guys. This forum is much better than the OTHER increasingly time wasting "Chinese Tools ***** (General Tools Discussion) Forum".

 

[duaneb9729]

normally there is not hot water to move to a radiator in a steam system, the steam flows by gravity to the radiator, and in a single pipe steam system the cooled steam turns to water but doesnt fill the pipe, so there is very little if anything to "pump" around.

Just for fun today I asked two of my "go to" guys about your system. For two reasons really, one I dont know everything and there is something to learn here for me as well as others. And two, I wanted to be sure that there is no danger to your mother or you or the system.

One fellow is rather gruff and to the point, and the other simply said dont let that guy back in the house, referring to the original installer.

Asking the guys at a company that sells infloor heating supplies for advice on a steam heating system? Your not going to get worth while advice there. Why you ask, How much steam experience would they have?, pex isnt rated to be used with steam.

Not that they dont have an experienced guy at the business but the one who recommended a different size pump, well he isnt the sharpest knife in the drawer.

Its your money and its your decision totally, but to just throw another pump on the system, well its just plain silly.

I am sorry if I sound like i am harping here, but if you were pulling an anchor around behind your car and wondering why you have poor gas mileage, the solution isnt a new anchor.

 

[duaneb9729]

If at all possible can i get some pictures of the installation or the radiator and pump set up?

 

[xroad]

The picture will have to wait. My mother's house is over an hour away. I will try to remember to bring my camera next time I go.

I think I may not have been clear ... The pump was not pumping steam. It is pumping hot water in the steam heat boiler. The pump is below the water level. Since there is no way of setting up a steam heat radiator in a basement room because the boiler is on the same level. That is why the hot water system was installed. The pump pumps the water up a pipe, across the ceiling and back down into a hot water radiator.

 

[duaneb9729]

Ah i see, i sure would like to see that set up, sounds like there is something to learn by seeing it.

If you can get a picture that would be great!

 

[Lovely World]

Yes, Trash pumps - they can tolerate solids. Not for your use though! Do you have a strainer in the system?

 

[xroad]

Yes, Trash pumps - they can tolerate solids. Not for your use though! Do you have a strainer in the system?

No strainer .... yet.... The way it was installed 12 years ago, they have to dent the adjacent hot water heater just to make it fit. The pipe comes out of the boiler, goes into the pump. Output of the pump comes out and bumps into the hot water heater and take a 90* turn upward.

I am deciding if I should put a shut off valve before the pump or a strainer. Shut off valve would make it easy to remove the pump for cleaning. No shut off ... I have to drain the boiler

 

[xroad]

I spoke with a guy at pexsupply.com. He was very helpful. The spec for the Taco 007 temp range is 230F, or around there, definitely a bit higher than the boiling point. The pexsupply guy said if it fail from temperature, it would be the seal leaking. In my case, there was never any leaks.

Cavitation damage ...... I don't even know what the word mean! too big of a word for me. Please explain.

The "fly-by-night" plumber from 12 years ago was long gone. He won't be back. I'm just trying to live with this setup until I come up with a better alternative.

I had considered tapping a steam pipe and run it across the ceiling and pipe the condensate return down to floor level before returning to the boiler. The condensate water will still have some amount of heat to throw off into the room. PROBLEM: This house is a turn of the century "Mini brown stone". All the pipes are treated with that miracle mineral ... asbestos! It is still solid and intact and not crumbling so I don't intend to disturb it.

I did some exploration. Found a section of the hung ceiling ... Opened it, and found that there was two steam pipes, each about 2-3 feet long that were not insulated. These two pipes ran along the edge of the ceiling before turning up into the floor/radiator above. Without the ceiling tile, it throws off quite a lot of heat. So it helped a lot. I'll replace the tile with a perforated metal panel. Hey, maybe if I add a blower up there, I may be able to remove the whole hot water pump kludge.