Radiant floor circulator pump in the summer?

[Blk88GT]

This may be a dumb question, but I'm getting conflicting information.

I'm being told to leave my circulation pump running all summer long to keep it from seizing/gumming up.

I'm using a Grundfos 3 speed pump with glycol in my system.

This seems very strange to me. I don't think there is any reason to keep it on.


What do the GJ experts say?

 

[Highbeam]

I call BS. That pump uses like 100 watts. How long would the thing have to run for no reason in order to cost you as much as a new pump? Don't do it.

 

[gpalmer77]

Would I run it all Summer? Nope.

Would I leave it off all Summer? Nope.

Like anything mechanical, I'd lean towards running it for a brief time at intervals. Maybe run it for an hour once a month?

 

[Jackfre]

One of the good things about Grundfos circs is that you can remove the screw on the motor cap, insert a thin screwdriver and give the impeller a spin. That will typically free up the pump. I think the greater issue is the glycol. What kind of mix are you running, how old is it and do you check the glycol periodically to make sure it is ok. Once it starts breaking down it can gum up.

This is a good reason to do a system flush with appropriate cleaners like Fernox prior to startup of a new system.

 

[Blk88GT]

Jackfre: Everything is brand new and has ~4 months of use, including the glycol. It's a 50/50 mix from sealed containers. There is approx 25 gallons in the system.

I didn't think running the pump all summer made any sense. Thanks for the info guys!

 

[SwerveDriver]

My thermostat triggers the pump(s) to run for a minute once a day regardless. I shut the element breakers off for the summer and let the thermostat and pumps do their thing.
S-D

 

[Blk88GT]

Swerve - What thermostat are you using? Interesting feature.

 

[anthony666]

a taco 'expanded' version pump control box accepts add on cards, one of the available cards features intermittent pump cycling .. the control box itself is the same cost as the regular pump controller .. the cards are about 40 clams more .. you're not just saving the pump, it also helps stop air build up and keeps the glycol in suspension .. i've seen that stuff gum up & crystallize in mixing valves etc

 

[SwerveDriver]

Blk88GT-

Thermostat is called an Aube TH135-01.

http://www.amazon.com/dp/B0007N73DW/?tag=atomicindus08-20

(I work a 9-5 job- not trying to sell you stuff).

Photo is a description of the Pump Protection feature.

Thermostat is connected to a Taco SR501 1 zone switching relay controlling two Grundfos pumps. I only can tell you that they work fine together- not sure if the individual components will work with other mfg'r components.

Taco Relay pump:
http://www.menards.com/main/heating...nents/1-zone-pump-control/p-191369-c-8523.htm

Best-
S-D

 

[BadgerBoilerMN]

Manufacturers do recommend "exercising" circulators in close-loop hydronic systems. We find that most pumps "stick" for lack of good water quality. All hydronic systems should be flushed, cleaned with solution, flushed again and properly treated.

If you use propylene glycol antifreeze you must check the pH every year. A 50/50 mix is generally too thick for anything south of the arctic circle.

 

[Zick]

What would you recommend using to "flush" a closed loop hydronic system that uses just plain well water?

 

[BadgerBoilerMN]

We test the water quality of every boiler heating system we service. We only clean, flush and treat new systems, systems we replace boilers in and old systems with pour quality water e.g. high or low pH, heavy dissolved solids or other undesirable constituents.

Generally, it is a bad idea to introduce fresh, oxygen rich water to any hydronic system.

When in need we use Fernox and Sentinal products to clean and treat the hydronic systems we maintain.