Built in check valves in circulators? Advantages and Dis-advantages?

edcrow

Why are these small check valves sometimes removed? I just replaced a Grundfos with a 3 speed 15-58 with a built in check valve. I left it in, however, why would they ever be removed?

Bob Bona_4

Not needed with zoning with zone valves. Or if there is some other site specific reason for it to be in or out.

WillieJ

Would you leave the check valves in if you zoned with circulators to prevent gravity flow?

Bob Bona_4

Absolutely.

hot_rod

Also, if the zone valves are on the return piping the check can prevent ghost flows. Hot boiler, circ off, hot rises up the pipe, cold falls down. If the heat emitters are above the boiler, of course.

No harm in leaving the check in, it has a very small effect on the circ performance.

4Johnpipe

They can create more head on a glycol filled system such as a snow melt zone this can be overcome with a properly size circulator. I have also had to remove them on systems (installed by others) that had misplaced the tank as in a zone valve system with the circulator and zone valves on the return side with the XP tank between the two causing the relief valve to pop. I pulled the checks in an emergency call then returned to re pipe the boiler.

icesailor

Just something else to go bad and you can't properly diagnose it because you may not be able to tell it is there.

IMO, they add a lot of unwanted restriction and turbulence that isn't needed.

hot_rod

The checks showed up in circs because the contractors and installers requested them. This goes back to the early days when primary secondary became the rage in hydronics in the early 90's thanks to Dan

The first versions were fairly restrictive, the pump guys changed the volutes to allow a larger size check, they add virtually no pressure drop as seen in the pump curves, regardless of the fluid.

Glycol does require careful pump sizing due to viscosity, the check shouldn't effect that.

All in all they provide more good than harm, prevent ghost flow and indirect tank over-heating for example, and can be easily deleted.

icesailor

Many Indirects need a heat trap.

Almost all HW mixing/tempering valves need to be heat trapped.

Many IFC's are just a band aid on an infection/ Poor design and implementation.

IFC's can get held open by all kinds of things. Broken paper clip. They are really hard to find because you never know the IFC's are installed.

Is "Ghost Flow" another bad thing like the air in systems that no one can explain where it comes from? If you get "Ghost Flow" and a IFC can control it, maybe you needed a good old fashioned flow check. Something you can manually open from outside of the piping.

The biggest drawback to the excessive use of IFC's is that some never learn the function of a flow check valve and how it works.

hot_rod

Come on Ice an IFC is a check valve, in a more convent location. How does the intent of this differ from the need or intent of a flo-check or other check in hydronics?

The pumps with IFCs inside are labeled as such, or a sticker "check removed" can be used.

Stop the un wanted flow condition at the pump not several feet away at the flo check location.

Broken paper clips inside your pipes, really Probably a roach clip. Bad for circ impellers, zone valves, TRV also.

billtwocase

I don't like them I prefer a separate flowcheck , if one is needed. I always enjoyed the 1st generation ones that were in Taco that would end up shredded in the impeller.

icesailor

@hot rod‌

"" Come on Ice an IFC is a check valve, in a more convent location. How does the intent of this differ from the need or intent of a flo-check or other check in hydronics? ""

Convenient for who? A lazy installer? Look at one and tell me how many feet of restriction they equal to?

"" The pumps with IFCs inside are labeled as such, or a sticker "check removed" can be used. ""

Where's the label? I've not seen any labels IN the boxes of new ones. Then, there's those brass isolation flanges that come with them. Have you ever put a sticker on one? Next time you or someone else has to fix a leak or cut into a pipe full of water, being held back from draining out naturally by a IFC, you'll have one of those Honesty Moments. They sluck.

"" Stop the un wanted flow condition at the pump not several feet away at the flo check location. ""

If you have to "Stop the un-wanted (ghost) flow conditions at the pump, you needed a check valve. If you have one, somewhere properly placed, you don't get Ghost Flow. Zone valves are just motorized flow-check valves. If you are getting Ghost Flow, it can often be traced to over pumping. Solving the over pumping problem with a restrictive plastic check valve is a step backwards.

I've never seen comparative circulator flow charts with and without IFC's.

"" Broken paper clips inside your pipes, really Probably a roach clip. Bad for circ impellers, zone valves, TRV also. ""

I've found all kinds of trash left inside plumbing and heating systems by careless installers. One hopes that the trash doesn't do too much serious damage. The Paper Clip looked more like a thin hair pin when I found it. Women don't wear hair pins any more. They used to call them "Bobby Pins". This was the thin wire kind. Like half a paper clip. Cut off. Or, maybe some woman at the factory dropped one inside. It matters not to me. I found it in a manufactured home Duplex, built in 2000 and owned by my son's Father In Law, used for summer employee housing. When I took it on in 2008, I noticed that although the heat wasn't used in the Summer, the 80M Munchkins and ID water heaters were. The first floor zones had the baseboard covers messed with. Like it was overheating and all the windows were open. Jamaicans don't mind heat. I found the pin when I was turning the place back on after being drained for the winter.

Some people don't like fixing things. Its easier to install something new and if it doesn't work, they can get someone else. I was "someone else".

You know, an old dead plumber said to me years ago. "You can teach a monkey to run pipes. It takes a smart man to fix them".

You learn by fixing your own mistakes and the mistakes of others.

icesailor

billtwocase said:

I don't like them I prefer a separate flowcheck , if one is needed. I always enjoyed the 1st generation ones that were in Taco that would end up shredded in the impeller.

Except that the original installer was never the one who went back on the complaint call. It was always "Someone Else".

Zman

I think this is a classic "it depends". In systems that must have flow checks like zoned circs or many CH/DHW configurations they work pretty slick. If you use isolation flanges on the circ, checking the operation or replacing the check is pretty simple.
Some applications just don't need a check and in others the check makes purging more difficult (lack of planning).

I have found that in the Grunfos Alpha for example the check makes the circ less sensitive to changing loads. In zoned applications there is a good argument to remove them.

I like that the check's effect on the circ is already figured into the performance curve. Many check valves have high resistance, just one more thing to calculate.

When you remove the check, you remove the sticker. Seems simple enough to me.

Carl

hot_rod

icesailor said:

@hot rod‌

"" Come on Ice an IFC is a check valve, in a more convent location. How does the intent of this differ from the need or intent of a flo-check or other check in hydronics? ""

Convenient for who? A lazy installer? Look at one and tell me how many feet of restriction they equal to?

"" The pumps with IFCs inside are labeled as such, or a sticker "check removed" can be used. ""

Where's the label? I've not seen any labels IN the boxes of new ones. Then, there's those brass isolation flanges that come with them. Have you ever put a sticker on one? Next time you or someone else has to fix a leak or cut into a pipe full of water, being held back from draining out naturally by a IFC, you'll have one of those Honesty Moments. They sluck.

"" Stop the un wanted flow condition at the pump not several feet away at the flo check location. ""

If you have to "Stop the un-wanted (ghost) flow conditions at the pump, you needed a check valve. If you have one, somewhere properly placed, you don't get Ghost Flow. Zone valves are just motorized flow-check valves. If you are getting Ghost Flow, it can often be traced to over pumping. Solving the over pumping problem with a restrictive plastic check valve is a step backwards.

I've never seen comparative circulator flow charts with and without IFC's.

"" Broken paper clips inside your pipes, really Probably a roach clip. Bad for circ impellers, zone valves, TRV also. ""

I've found all kinds of trash left inside plumbing and heating systems by careless installers. One hopes that the trash doesn't do too much serious damage. The Paper Clip looked more like a thin hair pin when I found it. Women don't wear hair pins any more. They used to call them "Bobby Pins". This was the thin wire kind. Like half a paper clip. Cut off. Or, maybe some woman at the factory dropped one inside. It matters not to me. I found it in a manufactured home Duplex, built in 2000 and owned by my son's Father In Law, used for summer employee housing. When I took it on in 2008, I noticed that although the heat wasn't used in the Summer, the 80M Munchkins and ID water heaters were. The first floor zones had the baseboard covers messed with. Like it was overheating and all the windows were open. Jamaicans don't mind heat. I found the pin when I was turning the place back on after being drained for the winter.

Some people don't like fixing things. Its easier to install something new and if it doesn't work, they can get someone else. I was "someone else".

You know, an old dead plumber said to me years ago. "You can teach a monkey to run pipes. It takes a smart man to fix them".

You learn by fixing your own mistakes and the mistakes of others.

Bobby pins! You must be old I haven't heard that term since the 60's

Y-strainers are another worth while investment, or dirt/air separators. They will keep bobby pins out of trouble in hydronic systems.

We did remove a brown cotton glove from a large air separator that was returned with "flow problems" S--- happens.

hot_rod

Zman said:

I think this is a classic "it depends". In systems that must have flow checks like zoned circs or many CH/DHW configurations they work pretty slick. If you use isolation flanges on the circ, checking the operation or replacing the check is pretty simple.
Some applications just don't need a check and in others the check makes purging more difficult (lack of planning).

I have found that in the Grunfos Alpha for example the check makes the circ less sensitive to changing loads. In zoned applications there is a good argument to remove them.

I like that the check's effect on the circ is already figured into the performance curve. Many check valves have high resistance, just one more thing to calculate.

When you remove the check, you remove the sticker. Seems simple enough to me.

Carl

We learned some expensive lessons when piping P/S. If the takeoffs were above the primary loop you really need check protection on the pump and return, S&R takeoffs. You can, and do get two direction flow in a pipe under some conditions.

The hydronic specific checks sold by Apollo, Watts, Caleffi and others have very low pressure drop, and a smooth tapered cone for quiet operation , and a bubble tight seal.

Swing checks have no place in hydronic, IMO they were designed to close and seal with higher pressure on one side. They have long travel length, leading to valve bang, are not bubble free seals, and depending on the style many do not allow the gate to swing completely out of the flow path, causing noise and turbulence. Save the swing checks for sump pumps

Paul48

"When you remove the check, you remove the sticker. Seems simple enough to me"

Personally....I like ice's idea of wedging it open with a paper-clip, myself. Bobby pins are too hard to find.

Steve Thompson (Taco)

Sorry, never been fan of built in checks (IFC's). Too close to turbulent flow for one (what ever happened to the old flow-check installed on the zone's return line). Also extremely difficult to troubleshoot and/or service (including getting rid of air locks). Unfortunately (depending on who you talk to) the pump industry followed the first "innovator" of this feature as many installers found the built in IFC to be a quick, easy and cost effective way to eliminate reverse flows - and for the most part they work.

Question to you Wallies, what is the maximum size (if any) of the circ that should have this "feature"?

Harvey Ramer

IFC's make for a nice clean looking install when you are pulling DHW off of the boiler loop of a ModCon. They are also quite handy in dual fuel situations where you may want to reverse the flow for freeze protection or something.

As far as building a new system, I always design to minimize the use of any flow checks. When I need to use them, I prefer (Dos Equis) IFC's. After all, It makes me feel like the most interesting man alive! lol

All in all, I do like IFCs as long as the pump is working off an external command for speed or performance. As far as servicing them, every new pump I install had isolation flanges. Lord, I have been so thankful for isolation flanges. They are just so darn convenient!!

icesailor

Isolation flanges are beautiful things. A whole tribe of them cost a lot of money. Along with all the other sundry things that are all now "Must Have" thinks on the latest FHW super efficient thing. When you get done adding up the cost of all these new and exciting must have parts, the price goes through the roof and the contractor hands the job off to a Scorched Air HVAC guy who puts the cheapest gas boiler and some air handlers with duct board and R-6 Flex Duct.

You don't even get anything for all the telephone time you spent getting prices for all the exotic equipment.

Bob Bona_4

Been using IFC's since they came out and ditched the clunky, leak potential flochecks that did the same job. Webstone or other iso flanges after the pump and good to go. Love 'em.

Jean-David Beyer

I am not a heating contractor, but I do have a pumped hot water heating system, zoned with circulators., with primary-secondary piping for the two heating zones. There is also an indirect with a circulator to control it. All these are Taco IFC models that came with a sticker that says IFC or something like that. The little IFC gizmos in the circulators prevent reverse flow, but they would not prevent ghost flow (I hope I am using the words correctly). Now my radiant slab zone does not get ghost flow because the slab is below the boiler, so it is effectively heat trapped. The indirect is connected across the primary circuit (across the boiler side of the P/S loop). There is a real flow-check valve in one spot to keep hot water from getting into the secondary loop when the boiler is running only the indirect. I am not positive it is actually needed, but the contractor put it in, because it was in the installation diagram of the I&M manual that came with the boiler. The engineer of the job actually read that manual.

As far as getting air out, there are lots of isolaton valves and boiler-drain type valves (used as purge valves) everywhere, So filling the system was no problem at all. But if I needed to drain the system, I could get almost all the water because the pipes above the IFC circulators have purge valves right there, so the water should come right out. Except for the two pieces of horizontal 1/2 copper tubing that is about 32 feet long. It takes impossibly long to get enough water out of those to solder joints. That was how it was when I bought the house. Hours to drain those.

j a_2

Check-Trol is the solution for circulator installations. Installing a Check-Trol on the discharge of the circulator gives you the features of a Flow Control Valve, Isolation Valve and Companion Flange. Another advantage of the Check-Trol is the minimal pressure drop, especially when compared to the losses that can be experienced when a check valve is installed internal to the circulator. The Check-Trol flanges are packaged with an isolation flange of the same size to create a pair. Capscrews and nuts are included.

Features and Benefits

Combines three valves in one: Isolation Valve, Check Valve and Companion Flange
Free floating flange allows easy alignment and installation of pumps
Prevents gravity circulation
Isolates the circulator so you don’t need to drain the entire system
50 state Lead Free

j a_2

The only thing I have ever found in a heating system is either heat or no heat…FYI the grunfos circs DO come with a sticker its a little white sticker…There is no way to make a general statement regarding there use or non use..Sit back ,look at the complete system ,and install as necessary…If you don’t like the other persons installation you have two choices, fix it or don’t fix it...

icesailor

Zone valves don't need IFC's or all the extra pipe and fittings that are required with separate individual zones with circulators.

Run that extra cost up and watch the Scorched Air systems go in like new fleas on a dogs back.

j a_2

Like I have said before, it depends on each system on an individual basis…there is no general statement that covers it all...

jonny88

I just had a Grundfoss1515 with check and it was whistling.I use isolation valves on all circs so it was an easy fix.This will however not prevent me from using again.I am not a fan of Taco cast iron flow check but I liked B&G flow check(bronze body with black dial for manual or normal.For now I am sticking with IFC.Every flow check I have ever used has had a problem at some point.For me I think its foolish not to put in isolation valves even though its competitive out there.Good enough for Hot Rod good enough for me.Some great points brought up though on either side.

Tinman

I'm with you jonny88. I, invariably, use pumps with IFC's and always use isolation valves. I'm not sure I could come up with a better example of being penny wise and pound foolish than not using ISO-valves. On some of the much bigger pumps I'll use a cone check.

icesailor

"" I'm not sure I could come up with a better example of being penny wise and pound foolish than not using ISO-valves. On some of the much bigger pumps I'll use a cone check. ""

Its not YOU being Penny Wise & Dollar foolish. ( the actual quote is a British comment where they use Pennies and "Pounds" instead of the Dollar), it is what the customer is willing to pay you for.

If you have four people figure the same job and three use zone valves and one uses all circulators. the zone valves will get the job because they are cheaper to pipe and install. All heating pipe in a new install was required to be insulated. Add the cost of the insulation and the labor to install it while you are piping or afterwards, and you won't get the total job. Where I worked, professional Insulators could do the whole insulation job for the cost of you or I buying the insulation.

Paul48

If you're refering to "In for a penny, in for a pound", that applies to a different situation completely. "Penny-wise, dollar-foolish", is appropriate.

bob_46

“Every system is perfectly designed to achieve exactly the results it gets.”

icesailor

bob said:

“Every system is perfectly designed to achieve exactly the results it gets.”

That's right. And if a potential customer gets 4 prices for a job and three are for $10,000 and the fourth is for $4,000 for that same job, they will go with the $4,000 price because the other three were trying to screw him.

Tinman

@ Ice...I was referring to the customer. I get paid no matter which way they decide. Early in my career, sometimes a pump didn't get the valves but in the last 20 years or so, every pump has got them. My customers see the value in them. And when I use zone valves, the single pump gets them too.

j a_2

I was kinda thinking I saw a note on the site that said no talk about pricing and be nice...

icesailor

No one was talking about pricing. It was an example.

Like the guy that Dan wrote about years ago that when asked for an "Estimate" to change a boiler, he replied, between $100.00 and $10,000. Yes, but how much is it going to cost? Well, if you want to know how much it is going to cost, I charge you for a "Price" and I charge $XXX for the cost of the estimate and time doing it. Which is included in the price. If you want to take my price and spread it around with my competitors, remember, you've already paid to have the job priced by me and that price is included in the price that I will do the job for.

How many times have some of us met the price shopper, trying to find the person who will to the job for $100.00 less than the lowest price given.

I knew of a contractor who had always used one electrician. He always was bidding against what was considered a premium and expensive electrician. After years past, the winning electrician was at a greet and eat and asked the higher bidding electrician how he could always beat him in price so he had to lower his prices to get the jobs? The which the quality electrician replied. "I've never given that cheap, no-good SOB a price in my life and if he walked into my shop right now, I'd throw his @$$ out. He doesn't pay what he agrees to and is just a rotten P&^%$. He never pays the final part of the contract until he gets up front money from the next job, and spends the winter in Antigua. I've never understood how you worked for the guy for so long."

No discussion of price there (IMO), just a discussion of the slugs out there who want to pick our pockets clean and get some to work and go broke to their advantage and our loss.