Recirculating Pump with Heat Traps

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Billwill.julz

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Hello all. I simply need some clarification as I just cannot find any answers online.

Apparently newer water heaters have heat traps (nipples?) which prevent recirculating pumps from mounting and/or operating with the water heater. I am confused as to whether this is because (A.) the pump will not physically mount directly onto the water heater (in which case a simple pipe extension would solve the issue) OR (B.) if it's due to the fact that the heat trap valve/flapper needs much more pressure to open (i.e. a faucet opening) than the pump can provide (very low PSI/GPM compared to the faucet).

It seems that heat traps are mandated oral water heaters at this point, so it is hard for me to understand why recirculation pumps may not be compatible. Any clarification on the matter would be very helpful. Thank you!
 
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Twowaxhack

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Who told you heat traps prevent a circulator from being installed or working properly?
 

Billwill.julz

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Who told you heat traps prevent a circulator from being installed or working properly?
Customers have left negative reviews on Amazon for a Watts 500800 recirculating pump stating it doesn’t work with all water heaters due to heat traps.

The most specific example is that a customer paid a plumber for installation, the pump will not “operate” (which in this case points to (B.) the valve flow theory), they called Watts (who confirmed there are known problems with some water heaters due to heat traps), then they have to pay the plumber to remove pump.

I will more than likely go with a Grandfos pump (unless recommended otherwise) but I’m trying to do my homework in case the issue is widespread.
 

Twowaxhack

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I’ve never had that problem and I’ve installed several grundfos that have the little bypass valve under the fixture.

I’ve installed several true circulators on heaters with heat traps as well, no problem.

But if I did have a problem I would remove the heat traps.

I remove them sometimes anyway.....I don’t like them.

What good is a heat trap if your going to circulate the water. Heat traps for for keeping the heat trapped in the heater.......LOL......So what’s the big deal about removing them, especially on the hot side ?
 

SHEPLMBR

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Just so you are aware, if the Watts one you were looking at, is the same type as the Grundfos, they are exactly the same (the one with the comfort valve that Two mentioned). I know this as my Watts rep explained that Grundfos makes them for Watts. I am in wholesale. I have never heard of this with either of them.
 

Twowaxhack

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Just so you are aware, if the Watts one you were looking at, is the same type as the Grundfos, they are exactly the same (the one with the comfort valve that Two mentioned). I know this as my Watts rep explained that Grundfos makes them for Watts. I am in wholesale. I have never heard of this with either of them.
That’s true, infact the Watts package deal has grundfos stamped on the bypass header.
 

Billwill.julz

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I’ve never had that problem and I’ve installed several grundfos that have the little bypass valve under the fixture.

I’ve installed several true circulators on heaters with heat traps as well, no problem.

But if I did have a problem I would remove the heat traps.

I remove them sometimes anyway.....I don’t like them.

What good is a heat trap if your going to circulate the water. Heat traps for for keeping the heat trapped in the heater.......LOL......So what’s the big deal about removing them, especially on the hot side ?
It’s great to hear you have not had issues in the past.

I’ve heard removing the heat trap would void the water heater warranty. I do like the 10yr warranty on heat pump waters heaters like the Rheem Proterra. Pardon my lack of understanding, but can the heat trap flap (rubber, correct?) be removed without destroying it in the event you would ever need to put it back?
 

Billwill.julz

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Just so you are aware, if the Watts one you were looking at, is the same type as the Grundfos, they are exactly the same (the one with the comfort valve that Two mentioned). I know this as my Watts rep explained that Grundfos makes them for Watts. I am in wholesale. I have never heard of this with either of them.
Wow! Great to know. I guess I’ll go with the “blue one” then as its $50 cheaper.

Maybe I should’ve mentioned, we are building a home with a dedicated return to the water heater. Obviously I would not need the comfort valve manifold included in the kit and plan only to use the pump. Do you guys recommend any other brand pumps above these two mentioned? I’ve read that Grundfos has a 10yr approximate life.
 

GReynolds929

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FYI it is not recommended to use a recirc on the Proterra. It makes the unit think it needs to be in high demand all the time.
 

Twowaxhack

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Billwill.julz

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FYI it is not recommended to use a recirc on the Proterra. It makes the unit think it needs to be in high demand all the time.
Thank you for bringing this up. I had always questioned this with ANY water heater, but always assumed that since the return water temp would be at least luke warm with a dedicated line, it would not significantly hurt the efficiency of the water heater (at least when compared to systems that use a cold water return like the Comfort Series by Grundfos).

I did come across this article by Rheem regarding recirculating pumps with heat pump water heaters: https://rmc-cdn.s3.amazonaws.com/site/rheemdotcom/resources/tech-bulletins/Heat+Pump+w-recirculation+1331.pdf

It seems that heat pump water heaters (or the Rheem at least) has an algorithm that measures incoming temperature in conjunction with overall tank temperature. It seems that Heat Pump Mode CAN potentially work as long as the return temperature is 15F less than the thermostat temperature setting (Energy Saver Mode is 25F less).

To help give the algorithm what it wants, how about installing a water pipe thermometer on the return line as a tool to help determine the timing cycles of the pump (using a digital timer). Here's an example, the water heater thermostat is set to 130F, run the pump until the pipe thermometer on the return line reads 130F, then set a timer and wait until the thermometer reads less than 105F (heck, even down to 90F), let's say it takes 2 hours.. Then set the digital timer to cycle the pump ON for 3 minutes/OFF for 2 hours.

What do you guys think?
 

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LIBERTYNY

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All the heat trap nipples I have ever seen restrict flow, which could cause a number of issues, sensors not tripping or overheating the motor. Sounds like to me you should just remove nipples and replace with a standard nipple or equivalent and a check valves.
Amazon sells alot of stuff from international markets which may not be the local joining standard (usually NPT) could just need a adapter not listed ? ?
As far as the warante the nipples can always be installed after the fact (un-ethnically). besides most manufactures never check the returns, espically not on common fail points like the heat trap nipples.
For a domestic recirc. pump I recommend a bronze taco, Water cooled 4 screw motor/coupling/bush replacement ! ! and the motors are cheap, water ways very rarely go bad.
 

Twowaxhack

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I prefer to put the water heater close to the point of use and make the water heater tankless.

The ultimate in energy efficiency.
 

Twowaxhack

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All the heat trap nipples I have ever seen restrict flow, which could cause a number of issues, sensors not tripping or overheating the motor. Sounds like to me you should just remove nipples and replace with a standard nipple or equivalent and a check valves.
Amazon sells alot of stuff from international markets which may not be the local joining standard (usually NPT) could just need a adapter not listed ? ?
As far as the warante the nipples can always be installed after the fact (un-ethnically). besides most manufactures never check the returns, espically not on common fail points like the heat trap nipples.
For a domestic recirc. pump I recommend a bronze taco, Water cooled 4 screw motor/coupling/bush replacement ! ! and the motors are cheap, water ways very rarely go bad.
Removing heat traps doesn’t void your warranty.
 

LIBERTYNY

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With a average loss of 70% power (plant to meter) it would be more economical to run a kruddy homeowner generator. In my area of South NY its cheaper to run your own equipment (half decent) than state owned electric company anyway. I know gas took a Major hit recently but #2 is decent right now at least historically.
 

Twowaxhack

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With a average loss of 70% power (plant to meter) it would be more economical to run a kruddy homeowner generator. In my area of South NY its cheaper to run your own equipment (half decent) than state owned electric company anyway. I know gas took a Major hit recently but #2 is decent right now at least historically.
I’m not concerned with loss from the power company to my house. Lmfao 🤣 !

And it wouldn’t be more economical or efficient because gasoline or natural gas is expensive too if using a generator.,.....

New York may as well be a different country as they do things different than in my region. Almost everything.......

How much power do you think a gas tankless uses ?

Go back and read my post again #14. Read it good......
 
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LIBERTYNY

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I’m not concerned with loss from the power company to my house. Lmfao 🤣 !

And it wouldn’t be more economical or efficient because gasoline or natural gas is expensive too......

How much power do you think a tankless uses ?
Im deeply concerned with what I pay alot for as its all ultimately passed on to the consumer.
 
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