Taco 007 - replace entire pump or cartridge

BoilOver

I have a taco 007 brass pump that is drawing 1.8 amps vs a spec of .75 amp. Do I need to replace entire pump or can I just replace the cartridge?

kcopp

If its a bronze circ it is less money/ effort to just do the cartridge. Make sure to get the right one. there are differences between the CI and the bronze.

hot_rod

Does it need to be a bronze circ? What is the application?
if you can, or do replace the circulator, and you are able too use a iron body, look into one of the ECM types.

BoilOver

It's on a closed loop boiler system-- trying to figure out if high amps indicates entire motor is shot and need to replace the entire thing(though would probably just use a cast iron version) or if I can just replace the cartridge. I am unclear why previous owner used a bronze pump

hot_rod

What is the voltage at the pump. Low voltage would show a higher amp draw. Check all connections, at the pump and at the other end.

I think if you shop around you will find the complete new pump is about the same or sometimes less than a cartridge. New, out of date code circs go through Craigslist and e-bay all the time for peanuts. If you are an online shopper

Is there non-barrier radiant tube connected to the system? Sometimes those jobs have nonferrous circulators.

Or sometimes "whatever is on the service truck" is what gets installed.

BoilOver

It is an older install with copper tubing

ESGWheel

Sharing my recent experience in replacing my Taco 007-F5 Circulator. While is does not address the issue of current draw that started this thread, perhaps it will help some fellow DIY’ers.

Existing Circulator started making noise. Decided to replace the entire unit. Reasons: (1) while possible to replace just the cartridge cost is ~ 80% of the entire unit; (2) current install used the flat red ‘rubber’ flange gaskets and they had hardened up and (3) there was some noticeable rust around the flanges. So for less than a Ben had new Circulator + new Bolt Set with the flat red flange gaskets. Note: the new Taco’s come with the ‘square’ rings, not the rubber gasket. And they do not come with new bolts. New pump also has square ring grooves in the flange face to accept the rings.

In researching found out an older post by Joe, a Taco Technical Service Technician, that Taco changed to square ring due to fact that the red gaskets can ‘take a permanent set, and with the materials expanding and contracting, Taco decided to change over to the o-ring type…’ So Square Rings it is.

Disassembly straight forward and not covered here. However when I loosened the existing bolts, it took only abt 1/8 turn before they were finger loose. This says to me that the Red Gasket was not really being compressed anymore and it was not leaking only due to the gasket ‘sticking’ to the flanges (later confirmed by needing to scrape them off). Also explains the scale and rust, since while no visible leaks, must have been weeping. It also means, IMO, that if I had replaced just the cartridge, it probably would have leaked due to disturbing the mating of the flanges. My new thinking: replace the entire unit with new if you have the red gaskets.

Clean up of boiler / pipe flange faces were accomplished with scrapper, wire brush and finally, do to some heaver scale, with an electric palm sander with 100 grit. Cleaned and until nice and shiny but still had some very minor pits, and right on the surface where the square rings would seat. Stuffed small rag into pipes during cleaning to keep out debris. Don’t forget to take out!

Found lot of comments about using a gasket sealant and how much to torque the bolts. Here is what I did.

I decided on Permatex non-hardening form a gasket sealant due to a concern about the small pitting on the boiler flanges. Used 'a small dab will do ya’ on the side that seats into the Circulator, spun it around a turn or two to evenly spread. Then set up for install but putting one side’s flange bolts pushed thru the boiler flanges. Idea is that will put a thin film of sealant on the square rings and need to get installed quickly before it sets, so with one side bolts sticking thru, can slide on the Circulator, stick thru the other bolts and it will stay put while you put on nuts , align and tighten.

Note about the nuts. These are against the Circulator flange that is a ‘slot’ not hole. So I used washers under the nut (not bolt) because I believe it will help spread the clamping force better. Or perhaps I am just set in my ways and nuts need washers under.

For torqueing the bolts, did not use a set value. Instead I heeded the advice from a post by Bob a few years ago that aligned with my own experience that says in part: ‘one of the main design features of the thick square section ring gasket is vibration isolation, but if you crank it down until the flanges almost touch you lose that function plus you distort the gasket and it is more likely to leak’.

I tightened down the boiler side flange first since its flange is hard mounted so to speak. I tightened the left side nut a little, then the right side a little, back to the left side, etc. I made sure the gap between the 2 flange faces was even and had a visible gap. I ended up with about 2 ½ threads showing and I measured the gap at ~ 0.056” Then did same on the pipe side.
Note: since it is more of a “snugged up” then torqued down, I did use Blue Threadlocker.

Filled it back up, fired it up and just perfect. No leaks.

BoilOver

Thanks everyone for the thoughts. I wound up replacing the entire pump and everything is performing well.