# HW Recirc pump suggestions?



## Stptog (Jul 13, 2014)

Need to run a single recirc line in a two bath house. Cannot run a gravity system, for those with more years in the trade what brand/size of pump have you had good luck with? Bronze or SS? Timer built in or not? A GFI is available in the boiler space if I choose that.. Thanks guys


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## SchmitzPlumbing (May 5, 2014)

i have always run laing pumps. i think it was an e1. i used to run them with timers but now i prefer the built in t stat. set the temp on the pump and its all automatic and plugs into a standard outlet.


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## jmc12185 (Aug 27, 2013)

How about a taco 006, with a strap on aquastat.

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## rjbphd (Feb 5, 2010)

Don't need no stinky pump on return line if piped in correctly!


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## plumbdrum (Nov 30, 2013)

Grundfos makes a nice plug in model. Timer or temp option with built in check.

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## jmc12185 (Aug 27, 2013)

rjbphd said:


> Don't need no stinky pump on return line if piped in correctly!


 For the millionth time...... Not all systems will work with gravity lines. He stated gravity will not work In this application. Sometimes, you just need a pump for it to work.

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## Stptog (Jul 13, 2014)

jmc12185 said:


> For the millionth time...... Not all systems will work with gravity lines. He stated gravity will not work In this application. Sometimes, you just need a pump for it to work.
> 
> Sent from my iPhone using PlumbingZone


Thanks JMC, I thought I made that clear in OG post, but this is a Phase 3 storage tank with NO gravity drain (must be siphoned) also a 3/4 mixing
valve is installed above the tank in an already tight space, It will be my challenge to figure out how to tie in the pumped recirc, nevermind the 50 ft run of pex through the basement crawlspace.

Id like to see the plumber who would be willing to try to pitch pipe through that space with foam board throughout... good luck!

And thanks for the suggestions!


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## Stptog (Jul 13, 2014)

SchmitzPlumbing said:


> i have always run laing pumps. i think it was an e1. i used to run them with timers but now i prefer the built in t stat. set the temp on the pump and its all automatic and plugs into a standard outlet.


Is this what you were talking about? it seems to have a set thermostat and timer built in. 

This type of system is awfully tempting using the cold supply as the recirc because of the reasons I stated in my last post... just makes me nervous. Usually things that seem to good to be true, turn out to be just that!
http://www.amazon.com/Laing-LHB08100092-AutoCirc-Recirculation-Timer/

Nevermind I found the one you were talking about


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## plumbdrum (Nov 30, 2013)

Stptog said:


> Thanks JMC, I thought I made that clear in OG post, but this is a Phase 3 storage tank with NO gravity drain (must be siphoned) also a 3/4 mixing valve is installed above the tank in an already tight space, It will be my challenge to figure out how to tie in the pumped recirc, nevermind the 50 ft run of pex through the basement crawlspace. Id like to see the plumber who would be willing to try to pitch pipe through that space with foam board throughout... good luck! And thanks for the suggestions!


Triangle tube offers a dip tube that may or may not have come with the tank for the auxiliary tapping for drainage and recirc .

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## Plumbus (Aug 4, 2008)

Running a recirc line back into a thermostatic mixing valve requires you do so to the mixing valve manufacturer's installation instructions. If the instructions are not with the valve, go to the manufacturer's website, find and and download the specific section of these instructions pertaining to recirculating hot water.

I've attached the diagram for a Watts mixing valve.


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## PlumberDave (Jan 4, 2009)

I have not had a single mixing valve recirc system work. By OEM direction or otherwise it gets too hot. The way I figure it, if you're not adding cold water to the mixing valve by running water, the rest of the time the pump is drawing off the tank and will end up with tank temps in the line. This is my experience with watts, amtrol and Symons?.


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## Coolcanuck (Jan 30, 2012)

Grundfos timer works nice, never had any grief.


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## Plumbus (Aug 4, 2008)

PlumberDave said:


> I have not had a single mixing valve recirc system work. By OEM direction or otherwise it gets too hot. The way I figure it, if you're not adding cold water to the mixing valve by running water, the rest of the time the pump is drawing off the tank and will end up with tank temps in the line. This is my experience with watts, amtrol and Symons?.


A dual aquastat set up with one right after the hot outlet of the mixing valve and another right before the recirc connection to the cold input side of the valve might eliminate this heat stacking effect. I don't know how this could be accomplished without confusing the heck out of both the mixing valve and the pump, but it is an interesting idea.


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## Stptog (Jul 13, 2014)

Ok, already existing is a Honeywell AM series 100-145. Here is the Honeywell schematic which is feasable to follow, (it is a hand dug equipment space so aka the well tank, boiler, and HW storage already make it very tight quarters) 

The "T" is the aquastat, do you think anything here should be altered or added?


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## Plumbus (Aug 4, 2008)

How about two aquastats with one on the return before the pump to turn the pump on when temp drops below 100° F and one on the tempered hot supply right past the mixing valve to turn it off when it rises above 125° F? Kind of like how floats on a non auto ejector pump work. It would cycle the pump quite a bit, but prevent dangerously high temps from building up in the line immediately downstream from the mixing valve.


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## Stptog (Jul 13, 2014)

Plumbus said:


> How about two aquastats with one on the return before the pump to turn the pump on when temp drops below 100° F and one on the tempered hot supply right past the mixing valve to turn it off when it rises above 125° F? Kind of like how floats on a non auto ejector pump work. It would cycle the pump quite a bit, but prevent dangerously high temps from building up in the line immediately downstream from the mixing valve.


I like it, now If I could incorperate a timer and some insulation, This guy might see the payback... someday..:yes:


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## Tommy plumber (Feb 19, 2010)

Stptog said:


> Ok, already existing is a Honeywell AM series 100-145. Here is the Honeywell schematic which is feasable to follow, (it is a hand dug equipment space so aka the well tank, boiler, and HW storage already make it very tight quarters)
> 
> The "T" is the aquastat, do you think anything here should be altered or added?














Figure 5 shows the re-circ line connecting back to the tempering valve. I have always piped the hot water re-circ line back directly to the bottom of the W/H. An advantage to piping it back to the tempering valve is less pipe. A disadvantage is that the luke warm water only mixes with outgoing hot water instead of returning to the W/H and being re-heated. 

Your call.

That drawing is goofy. In theory, the returning hot water in the re-circ line could be cold when it returns back to the tempering valve. I'd pipe the re-circ to the bottom of the W/H so it gets re-heated.


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## Stptog (Jul 13, 2014)

Tommy plumber said:


> Figure 5 shows the re-circ line connecting back to the tempering valve. I have always piped the hot water re-circ line back directly to the bottom of the W/H. An advantage to piping it back to the tempering valve is less pipe. A disadvantage is that the luke warm water only mixes with outgoing hot water instead of returning to the W/H and being re-heated.
> 
> Your call.
> 
> That drawing is goofy. In theory, the returning hot water in the re-circ line could be cold when it returns back to the tempering valve. I'd pipe the re-circ to the bottom of the W/H so it gets re-heated.


I agree with you in principle, problem is I have no gravity drain on the tank!


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## dclark (Dec 12, 2010)

Tommy plumber said:


> That drawing is goofy. In theory, the returning hot water in the re-circ line could be cold when it returns back to the tempering valve. I'd pipe the re-circ to the bottom of the W/H so it gets re-heated.


 
Colder when it returns, yes, which would cool the element in the mixing valve, forcing the water to take the other path available... to the cold inlet to the tank, to be replaced by the hotter water from the hot side to the mix.

Pipe it exactly the way the shows, including the check valves.

I've repiped many that were not installed correctly to this configuration, and it works.

The manufacturers are good at designing things that work, if we can follow their instructions.


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## plumbdrum (Nov 30, 2013)

If you look in the triangle tube smart tank instructions, install a dip tube in the auxiliary port for drainage and recirc line. That how I always installed , no issues

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## Stptog (Jul 13, 2014)

plumbdrum said:


> If you look in the triangle tube smart tank instructions, install a dip tube in the auxiliary port for drainage and recirc line. That how I always installed , no issues
> 
> Sent from my iPhone using PlumbingZone


I haven't had a chance to check triangle tube yet, how exactly is installing a dip tube going to help me with drainage?

Thanks for all the suggestions too btw.


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## plumbdrum (Nov 30, 2013)

Stptog said:


> I haven't had a chance to check triangle tube yet, how exactly is installing a dip tube going to help me with drainage? Thanks for all the suggestions too btw.


The dip tube will siphon with a pump. Just look at the book, it will explain everything

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