# Need Help With Recirc and Tempering Valve



## 5onthefloor (Sep 13, 2017)

Hopefully one of you commercial gurus can help me with this one. I've mentioned before that I mainly do residential service and rarely mess with commercial anymore but I got stuck with this one. Basically it's an event center with a kitchen, 2 public bathrooms and a break room. Problem is public restrooms and break room not receiving any hot water. The kitchen is getting hot water. The plans show that the tempered hot water line originates from this mixing valve but I can't confirm through the ceiling grid because there is sheetrock about 8" above the grid covering all mechanical. 
The building supposedly has never had hot water and now they are trying to fix it because they want a food safety permit from the city. 
I was told the mixing valve needs a bypass but I am not sure how or where to hook it in. Any help appreciated and also would like to know why this bypass is needed so I can be aware in the future. Here are some pics....









Sent from my SM-G930V using Tapatalk


----------



## GAN (Jul 10, 2012)

No hot water at all, is the heater firing up?

The tempered water would be required on restroom hand washing sinks.

Are they getting water but not hot? If so you try to adjust the tempering valve control. 

Can't see the brand tempering valve, there should be integrated stop valves on it, are they open? If you not getting any water on the hot side these both may be off at the tempering valve.

Water should be at least 100 to max 120, for hand washing. Your specialty sinks, food prep, dishwasher or 3 pan, service sink no tempered water. 

All restroom/hand wash sink would be fed hot through the tempering valve. Other fixtures not required to be tempered would be fed directly form the water heater.


----------



## Toli (Nov 7, 2015)

That’s a Leonard tempering valve. If the circ line is trying to circ tempered water it’s not going to work as shown. Leonard has a very specific piping arrangement for their valves if using a circ line. 

Assuming the tempering valve in the pics serve the fixtures not getting hot, I would first try and determine if it’s a case of a long distance or a valve that’s not working.


----------



## 5onthefloor (Sep 13, 2017)

Yes it's a Leonard valve. Integral stops are full open. There is no hot water at all to tempered fixtures. The kitchen does get hot water so no hot water is limited to tempered fixtures.
I think Toli is correct, this valve is not piped correctly but I'm not sure what configuration should be.
There is a 3/4" plug at bottom of the valve. I should have mentioned that I did replace internals of the valve. It's got a spring and yoke assembly. 

Sent from my SM-G930V using Tapatalk


----------



## Toli (Nov 7, 2015)

http://leonardvalve.industrysuite.c...uctFile.asp?i=LeonardValve|10506|PDF|G-26.pdf

That’s the piping for a TM -26. I’m not sure which valve you have. Poke around Leonard’s site to find the correct valve and diagram. You must follow their instructions and piping diagram. You will have nothing but grief if you don’t. Go ahead. Ask me how I know.


----------



## Plumbus (Aug 4, 2008)

The tempering valve as shown will not pass hot water when the downstream faucets are not in use. Removing the tempering valve may not solve the problem because line downstream of the valve probably doesn't have a return to the heater. If it does, put a couple point of use tempering valves (see attached) at each fixture that requires tempered water. 
http://bim.cashacme.com/item/thermostatic-mixing-valves-tmv/tmv-hg145-lf/24524

The easiest way to run hot water in a multi temp application (like a restaurant) is to run a complete loop at the maximum temp required and use adjustible point of use tempering valves at fixtures requiring less heat.


----------



## 5onthefloor (Sep 13, 2017)

Toli said:


> http://leonardvalve.industrysuite.c...uctFile.asp?i=LeonardValve|10506|PDF|G-26.pdf
> 
> That’s the piping for a TM -26. I’m not sure which valve you have. Poke around Leonard’s site to find the correct valve and diagram. You must follow their instructions and piping diagram. You will have nothing but grief if you don’t. Go ahead. Ask me how I know.


It is definitely not piped in that configuration. No wonder it has not been working 

Sent from my SM-G930V using Tapatalk


----------



## Toli (Nov 7, 2015)

Plumbus said:


> The tempering valve as shown will not pass hot water when the downstream faucets are not in use. Removing the tempering valve may not solve the problem because line downstream of the valve probably doesn't have a return to the heater. If it does, put a couple point of use tempering valves (see attached) at each fixture that requires tempered water.
> http://bim.cashacme.com/item/thermostatic-mixing-valves-tmv/tmv-hg145-lf/24524
> 
> The easiest way to run hot water in a multi temp application (like a restaurant) is to run a complete loop at the maximum temp required and use adjustible point of use tempering valves at fixtures requiring less heat.




I agree. Trying to circulate tempered water consistently is tough.


----------



## 5onthefloor (Sep 13, 2017)

Toli said:


> I agree. Trying to circulate tempered water consistently is tough.


Yeah I know I've seen more and more commercial buildings with individual mixers at the faucet rather than one for whole system. I might mention this as option 2 tomorrow at the morning meeting. Eliminate mixing valve and add mixers underneath faucets

Sent from my SM-G930V using Tapatalk


----------



## Tommy plumber (Feb 19, 2010)

5 on the floor- that swing check is probably frozen; I'd replace it and install it vertically.

Edit: I meant to say horizontally. Not vertically.


----------



## GAN (Jul 10, 2012)

Kill the circ pump and verify your getting hot water through the valve first. Make sure its working before you move on.


----------



## 5onthefloor (Sep 13, 2017)

Thx for the help guys. Boss hasn't heard back from owner but more than likely I'll be sent back there. I'll update with solution and outcomes 

Sent from my SM-G930V using Tapatalk


----------



## Plumbus (Aug 4, 2008)

5onthefloor said:


> Yeah I know I've seen more and more commercial buildings with individual mixers at the faucet rather than one for whole system. I might mention this as option 2 tomorrow at the morning meeting. Eliminate mixing valve and add mixers underneath faucets
> 
> Sent from my SM-G930V using Tapatalk


A point of use temperature limiting device (ASME 1070) is intended to limit the hot or tempered water temperature supplied to fittings for fixtures such as sinks, bidets, lavatories, and bathtubs to reduce the risk of scalding.
Point of entry tempering valves (ASME 1017) are not designed for that purpose and don't meet the code requirement for same.


----------



## breplum (Mar 21, 2009)

To meet ASME 1070 protection as Plumbus notes, the easiest method is to replace/use lav faucets that are ASME 1070 approved. You can find them readily. 
You would then want to eliminate the Leonard mixer.
While you have everything shut down, correct the many issues present. From what I can see, there is no good method of shut-down on the water heater. 
I would put valves on both the cold and hot.
Additionally, I always want to have a way to replace the expansion tank w/o headaches later, so: Use solutions from Webstone or just build it using LHBV for isolating the tank branch and a tee with side tap of a HB to relieve pressure.
One personal note from experience. If you ever try to use a ASME listed 1070 faucet with a under-sink instant electric point of use water heater, you mostly get a bad interaction.
What happens is that the faucet reacts to the hot water coming in, self-adjusts its' flow to protect the output limits, but that reduced flow affects the output temp coming from the instant hot water unit, which then reacts to the flow and it all becomes a weird feedback reactive loop resulting in fluctuation of delivered temperature.


----------



## Toli (Nov 7, 2015)

Plumbus said:


> A point of use temperature limiting device (ASME 1070) is intended to limit the hot or tempered water temperature supplied to fittings for fixtures such as sinks, bidets, lavatories, and bathtubs to reduce the risk of scalding.
> Point of entry tempering valves (ASME 1017) are not designed for that purpose and don't meet the code requirement for same.




My code will allow either to be used for final temp regulation. But it’s hard to keep things consistent in a large facility with 1 1017 valve in a far off mechanical room. 

1017’s usually way over sized as well.


----------



## indyjim (Apr 29, 2017)

You need a circuit setter. The return needs to run into the cold supply of the tempering valve, and back into the hot water tank for periods of inactivity. Lots of contractors do not recirculate the tempered line at all because it's a PITA to set up correctly. I've seen tempering valves above the bathrooms with the re circulation line returning before the branch to the hot feed. 


Sent from my iPhone using Tapatalk


----------



## 5onthefloor (Sep 13, 2017)

Yah the boss was there today walking the jobsite. I guess the customer did not like my answer so well see how it goes

Sent from my SM-G930V using Tapatalk


----------



## rjbphd (Feb 5, 2010)

Oh what the fox !!!

Sent from my SM-G386T using Tapatalk


----------



## 5onthefloor (Sep 13, 2017)

rjbphd said:


> Oh what the fox !!!
> 
> Sent from my SM-G386T using Tapatalk


Yah frustrating. Then today boss calls me asking if I went up to the attic. I tell him I had asked and they told me no access to it. I've been doing service work most of my career but this company where I am at is not a full service company so they don't give me enough freedom of help to properly diagnose clusterfux like this one. And I'm the type of guy that needs closure for these types of calls. If gives me much needed experience but I digress

Sent from my SM-G930V using Tapatalk


----------



## Lannewats (Nov 5, 2017)

Told thanks for the link I save all my install manual to iBooks hate using internet in the field.


----------

