TACO 007 circulating pumps propeller/shaft separation?

[pkrsiak]

System Description:
1. The boiler is cycling normally, low 160°F, and high 185°F, 15 years old without problems.
2. The boiler is Weil-McLain GV5, has its own Taco 007 circulating pump, which is running when any of the zone will call for a heat.
3. All four-zone circulation pumps are running individually when there is a call for heat distribution.
4. The boiler is outputting 185°F hot watere as per current settings.
The problem:
1. The baseboard radiators are just lukewarm; therefore the system is not distributing sufficient BTU’s.
2. The system is not performing for only about few days without any other previous symptoms.
What was done?
1. Replaced 6 auto air vents,
2. Checked the pumps not physically just audibly
3. Flushed, purged, and re-started the system.
4. Air venting with increased temp to high 210°F
Result: About the same heat distribution.
Questions:
1. Have anyone experienced the propeller - shaft separation on the Taco 007 circulating pups?
2. What else the problem might be?

Best,
Pavel

 

[rodeoman]

there is a posibility that the pump is no good, you might be heating by gravity. do you have power to the pump? if you have isolating valves shut them off remove the pump impeller by removing the 4 screws on the housing and remove it, turn on the power and see if the impeller is turning..if you do not have isolating valves then drop the pressure in the boiler shut off any air vents to create a neg pressure then remove the impeller assembly. good luck>>>

 

[Sponsor]

 

[hj]

pumps

If I read you posting correctly you have five separate pumps on the system. If so, what is this particular pump's function, since the zones seem to have their own pumps?

 

[pkrsiak]

Boiler's pump draws some of the heated water back to the boiler through a mixing chamber to prevent a totally cold return during startup to minimize a condensation. The pump was already installed in the factory; the never GV series models have actually two pumps.

 

[Jimmym]

Sounds like the 007 at the boiler is the primary loop circ pump. Are ALL the baseboards experiencing this problem? If so, I'd say it's a primary loop problem. How long does the boiler run to get from 160 to 185 when there's a heat demand? What is the temperature of the piping at the boiler supply and return?

 

[pkrsiak]

The power to all pumps is supplied; I tested for voltage each individually and I also can hear them with a stethoscope. I reset the setting to 220°F and let it run for several hours continuously (I like subtropical temperature in North East ) and than the gargling started and the vents were making steam. The house is one level 2500 square feet, most likely this was trapped air somewhere. The setting is back to the original, the IN is cooler, the gauge is reading 185°F again, and the pressure is just a hair under 20 PSI.
It seems that the system is fine now, definitely huge improvement.
What bugs me is that the system was working for 15+ years flawlessly. I did not find the cause – how the air entered the system?
Thank you guys, you are all great, a lot of good suggestions.

Best,
Pavel