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icesailor

icesailor

Joined on September 13, 2010

Last Post on July 24, 2014

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Air eliminator brands:

@ July 20, 2014 3:29 PM in Constantly purging air in hydronic system

I'm quite familiar of the brand you mention, made in Europe and now sold by an American company. Whenever I replaced one, I always unscrewed them (by hand) and put some silicone grease to the threads and O-Rings. So I could get them apart later to clean the seat. Experience has shown that the seats don't clean easily and just replacing them was cheaper in the long run. They are sold cheap anyway. I used to replace more than 12 but less than 60 (I think) in the course of a year when I found them leaking. When I started to crank down on the cap, it didn't change anything. It stopped the white stuff from forming, and the system still worked as usual. And customers weren't getting charged for lots of leaking vents. I used to pipe an air chamber above the PR valve to collect air bubbles out of the boiler. They leaked first and I didn't have all the 30# Pressure relief valve replacements.

High systems:

@ July 20, 2014 3:16 PM in Constantly purging air in hydronic system

That's true. In open tank gravity systems, the overflow tank in the attic to a place where the system level was below the entrance of a radiator was long and the water volume was high. In a closes HW BB system that is series looped, had very little extra water in it. As long as someone kept the boiler/system filled to the red mark on the altitude gauge, the system was always full. Who ever checks system pressures and adds water.

Outside Logging:

@ July 20, 2014 3:08 PM in DHW configuration

In my (easily disputed) opinion, you are using some form of data logging that is using the outside air temperature compared to the temperature of the boiler as if it was winter time and you are trying to heat a structure.
I think that when you do what you are trying to do that is to compute your hot water temperature, it is counter productive, With a indirect heater, the system and real world sees the Indirect as a heating zone and you are trying to heat the structure with it. Because you have no heat loss to the outside, but only through the incoming cold water and how much you heat it, it just can't compute. If it is heat and you can develop a known heat loss against a known constant, what you are doing, won't show you savings except to show you when the burner runs or not. With domestic hot water, the issue is to get the amount of hot water you need in a given amount of time. The amount varies with demand. The more water you have coming out of the hot water side to get the comfortable water temperature you need, the faster you will run out. The hotter the hot water, the more cold you need to get it to the temperature you need for comfort. And you won't be running out of hot water in the same hotter tank.
If you had a Mod-Con, and you ran it with DHW priority, you could probably set the high limit priority to 140 degrees in the Spring, Summer and Fall and have lots of hot water. If you have to drive from point "A" to point "B" that is 40 miles away, it will take you 2 hours at 20 MPH and one hour at 40 MPH. But you get there just the same. How long it takes is up to you.

Not Cool: Techman & Meplumber:

@ July 20, 2014 12:44 PM in Not Cool: Techman & Meplumber:

I really appreciate your input on my situation. I wanted to keep you informed.
I may have other issues with the replaced system. not seeming to work as well as the old, but one thing is that decreasing the heat gain is only a step forward. The attic insulation is a mess. Over the years, different people rooting around for alarm systems and cable TV systems have caused the insulation to be piled up in some places and non existent in others. I know the limitations of IR thermometer guns. But relatively, they show something. If the room is set at 79 in the AM and it is 80 degrees OAT, the inside floor is 75 degrees, and the ceilings are all 79+/- and one room is 78degrees, it gives you a guideline. But in the room that is 78*, there is a closet with an access panel in the ceiling with no insulation, and the side facing in measures 101 degrees, it is a good indicator that there is little resistance to heat gain in that area. I know that the area above this closet has had all the insulation pushed away and not put back. I'm going to have additional insulation blown in.
The issue I discovered should be of interest to you. My theory that adding additional attic ventilation (full length ridge vents) 3 years ago has added to the problem by increasing the humid airflow in the attic increases heat gain that is putting additional load on the system. I have three recessed ceiling lights in the ceilings. The three incandescent bulbs add heat to the building. They aren't IFC so they can't be covered with insulation because the air is part of the cooling part of the listing. So, I changed them to LED spots and dimmers and I will do something to cover them up so the insulation isn't in direct contact with the housing. The worst that can happen is that they might blink off and on if they get too hot. They are only 12 watt LED bulbs though. But when I stuck my hand inside to guide the new bulbs in to the sockets, I was surprised to feel how much humidity/moisture I could feel in the top of the housing. It was extremely noticeable.  I suggested that the moisture was traveling through the insulation and through the gypsum ceiling, where it was being absorbed by the cooler and dryer air. It never goes above 50% inside while yesterday, it was in the 80% range outside. The only place I get any condensation is on the closest and coldest metal ceiling registers. And the condensation shows up first on the ceiling, where the register meets the sheetrock and comes from under the grill. Yesterday, during the hottest part of the day, the structure gained 1 degree (78* to 79*) and the humidity outside went to over 80%. But the humidity inside stayed below 50%. The closet room with the access, the surface temperature went from 101* to 106*.
In my life as a Hydronic Heater, I found a lot of problems with cold air infiltration in recess ceiling lights. Enough so that in a well and properly ventilated unconditioned space that had recessed ceiling lights, you could have a 28 degree OAT day with 35+ MPH wind and not be able to get the room to a temperature above 60 degrees and the boiler is off on high limit. Go back on another day and the OAT is 10 degrees, the same room is 70 degrees inside and the boiler is cycling. On the cold, windy 28 * day, inside the light is 34 degrees inside the light housing. On the 10* day, it is warmer, maybe 45 degrees inside the light housing. It doesn't matter if they are IFC rated or not. They still leak/infiltrate air. If you ever have a lack of cooling call, and there are recessed ceiling lights, especially in cathedral ceilings, look there. I promise you it will be surprising to you how much is lost there.
Additionally, the AH has some EEV Motorized valve assembly that controls liquid going in to the expansion valve. It stopped working and the system stopped. It must be a "Normally Open" valve because when they by-passed it, it became fully opened and the vapor return line is now very cold and at the compressor, it is now sweating when it is running. That should qualify for something. I don't think it was ever working properly. I never saw the condenser sweat since it was installed. It does now. Like the one beside it.
I felt that it was extremely restricted in the return airflow. I have always used quality air filters. I change them once a month and I can see the dirt on the air side. If the AH is running when I take off a filter, it will try to suck it back. When I try to put it back, it sucks it right out of my hand. The louvered cover they send to use in place of a bottom inlet will do the same. It adds a lot of restriction to the intake. That's why I want to cut out the louvers. The other day, the inside temperature started to go up while running. I took off the filter and louvered panel. Air flow improved. If the bi-fold louvered door is not quite closed, the intake return fan will suck it closed. The better the filter, the more restriction it can add. I figured that out. Cheap filters have a place.
If you have done any small boat single handed sailboat racing like I have for most of my life, you appreciate the value of good, clean and undisturbed air.  It would have been better to use the bottom return because there is less turbulence in the air going through the louvers than when it is only a few inches from the intake.filters. Its what makes airplanes fly and sailboats sail.

A question:

@ July 20, 2014 11:39 AM in Height vs SubCooling vs Freon Charge

You all use the term "Lift". That usually means in the world of pumps. that you are "lifting" the liquid UP by suction. If the compressor is at ground level, the compressor is a pump. Therefore, the liquid being raised to a level or "head" is actually being pushed UP to that point.
So, the question I ask is, don't the same rules for pumping hot water in a heating system apply in pumping refrigerant? That if you pump UP to a head level that is too high, won't you get gas expansion from a liquid if you go high enough that the available pressure can't keep the liquid from boiling? Wouldn't that phase change cause a loss in available heating/cooling BTU's? If the only thing you want to go into the expansion valve is liquid, isn't it a bad idea to have gas bubbles mixed in the liquid too?
Just asking. I don't know.

Cracked Up:

@ July 20, 2014 11:23 AM in No end of aggravation

Did you use that dreaded Teflon Tape and paste on the male nipple threads or did you use some antique pipe dope compound?
Years ago, HTP had a problem with their Super Stor indirect's leaking where a flare adapter went in to the coil. They came out with a tech bulletin for the leakers to only use a high quality Teflon paste pipe dope and they listed two. One was or was similar to Rectorseal #100% Virgin Teflon. By using that product, you could tighten the flare adapter with a pair of pliers and not have it leak. They also suggested that in testing, they found that it could be just hand tight and it wouldn't leak.  That was no new news to me. I used Teflon Tape and some form of Teflon tape for over 40 years. I tighten up small fittings with a pair of 6" or 10" Arc Joint pliers and never have a leak. A lot of people WAY OVER-TIGHTEN small fittings. 1/2" black malleable fittings are a good example. I've seen installers crank a fitting around for another turn with 18" pipe wrenches. Because it didn't seem tight enough when they were getting to the spot. Then, while going around again, it got harder and harder, but 3/4's of the way there, the turning suddenly gets easier. You just destroyed the fitting by stretching it. You can do the same with brass fittings except that they just continue to stretch. Except that the new no-lead or tin fittings are brittle and instead of stretching, they crack later because the fitting is left under tremendous tension.
Before you condemn Brass craft out of hand, try properly applied quality tape. Even if it seems loose as you get to the spot, it won't leak. And that doesn't mean using 3/4" wide tape on 1/2" fittings with a pile hanging over the end of the threads and another pile hanging past the ends of the threads. No more than 3 wraps.
If it's a transitional fitting, like going from 1/2" or 3/8" IPS to 3/8" OD compression stops, if it cracked, you had it too tight. If it leaked, you could have gone around another turn. Its not like it is a tee in the middle of a large section of screw pipe.

Hydroscopic Vents:

@ July 19, 2014 9:37 PM in Constantly purging air in hydronic system

HR, those may work well when first installed. Every type of air elimination device I have encountered, sooner or later, fouled in the venting mechanism. Even like Taco #400 float vents. You put them on top of a boiler or on the top of a heat system and they vent air like a bandit. After time though, when there isn't enough pressure in the system (and even if there is), sooner or later evaporating water/air gets under the seats and they start leaking small amounts of water that evaporates and leaves that white stuff behind. With float vents, you can crank the cap and stop them from leaking. Any air will be absorbed. I used to change many. many every year that were leaking. Like every few years. I started cranking the caps and I never had another problem with leaking air air problems. I put Taco 417-3 vents on a few radiator systems and when I refilled the systems in the Spring, I never had to vent them. In the fall when I drained the system, I never had to open the vents. They automatically added air onto the radiators and broke the vacuum.
It was all part of the theory I developed about heating systems not having enough water pressure in them.
Look at the average float vent on a boiler or an old air scoop where the cap is left loose to vent air. It is all white and nasty. I've had micro bubble eliminators that leaked out the end and got all white with the nasty's. I don't know if you ever stood on a 6'  step ladder with a couple of 3' pipe wrenches fit between pipes to unscrew that micro bubble cap to replace it, but it's safer to just put a 1/2" IPS coupling and a reducing ell with a float vent and a tight cap.

Big old pipes:

@ July 19, 2014 9:21 PM in What about constant circulation and outdoor reset for an old high mass system

In my experience and opinion, you have the perfect system for constant circulation/ODR (Out Door Reset)
A really nice way to do it is with something like a Taco "I" Series 4-way mixer and make it primary/secondary through the use of the 4-way with two circulators. That way, you can keep the boiler water over the condensation point (140 degrees) and the ODR part of the valve will run the gravity part of the system at whatever temperature is needed, set by the outdoor temperature. If you have just a pumped but converted gravity system, unless you can let the circulator run to its hearts content, the closest radiators to the boiler will always be hotter that the ones farther away. When the ODR control works, it might only need 115 degree water to heat the whole house/system, and because the system is pumping 115 degree water through the entire supply, the system will go in to total balance. Which was the idea of a gravity system as designed. You can add TRV's but if you try the 4-way, it will work. And you might find that the TRV's don't do what you would expect.
If you try to pump 115 degree water continuously through the system, the boiler will fail because of condensation. Condensation is really bad for a system.

Differences:

@ July 19, 2014 9:07 PM in DHW configuration

The original post mentioned a boiler and using two gas water heaters that sounded like they were piped in series because one hardly ever ran, and the other was doing all the work. That an option was being considered to use a 60 gallon indirect. All well and good. Then, it got in to heat traps and etc. My comments were related to the fact that the two water heaters, properly pipes, held more hot water etc.
Retirement?
Some have no idea how far we are advanced on the North about heat loss/gain and how to heat of cool a building.
I don't think that I have seen a "normal" heated building in the North, be under rated/under heated. Most of us understand and know how to deal with heat loss in a structure like we might discuss the latest sports team.
When it comes to cooling and heat gain (I always thought it was the same only in reverse), it's advanced rocket science. Done by FM.

As far as Florida rain, the Summer is the "Rainy" Season. Someone once said that in Oregon, it rains all the time. In Texas, it rains all at once. Same with Florida. Only South Florida is one of the lightning capitol's of the world. So, if you really enjoy big loud boomers, come on down. Every morning and every afternoon. When it comes down, it comes down like Hell in a bucket. A mile away, not a drop.

RTV:

@ July 19, 2014 3:10 PM in Silicone steam pipe through floor?

High Temp. RTV is used regularly on automobile engines. They run really hot. Hotter than your average residential low pressure steam system.

Auto Vents:

@ July 19, 2014 3:03 PM in Constantly purging air in hydronic system

If you have this type of air vent on emitters at the top of the system, it absolutely will not vent air if the system is full and only water is there. If the system goes negative, this type of valve will absolutely let air into the system, and you will never know it. The one I have the most experience with is the Taco #417-3. Taco has re-done their web site and the only thing I can find is this PDF and there is one on page 2. If you have one of these on a system, and you don't have adequate pressure, it will add air into the system.

http://www.taco-hvac.com/uploads/FileLibrary/100-7.1.pdf
and:
https://www.google.com/search?q=coin+air+vent+for+hot+water+baseboard&tbm=isch&tbo=u&source=univ&sa=X&ei=_cDKU5_APMeLyATmsID4BQ&sqi=2&ved=0CEoQ7Ak&biw=1093&bih=434#facrc=_&imgdii=_&imgrc=naSMbHLcXok8nM%253A%3B6XqnajgrV6ogkM%3Bhttp%253A%252F%252Fs3.supplyhouse.com%252Fimages%252Fproducts%252Fzoom%252F417-3-2.jpg%3Bhttp%253A%252F%252Fwww.supplyhouse.com%252FTaco-417-3-Coin-Vent-11389000-p%3B500%3B500

Line It:

@ July 19, 2014 2:39 PM in Do I need a chimney liner?

There's no question it needs to be lined.

Its more important to decide if it can even qualify to be lined. Anyone can line it. But can it be lined, and it still be a legal chimney/flue?
I was a mason's helper/mason before I was a carpenter, before I was a plumber. I know how to mix mortar in a mortar box with a mortar hoe and how much water to add to the mix without it turning to soup.

Higher Pressures:

@ July 18, 2014 10:52 AM in Constantly purging air in hydronic system

Yu don't need to check the pressure at the top of the system. Just maintain adequate pressure in the system. If the pressure gauge on the boiler is reading less than 10#, either the fill valve isn't filling, or the gauge is bad.
Do you understand what happens to a underwater diver when he/she dives below the surface? The oxygen and Nitrogen in the blood get compressed by the increasing pressure of the surrounding water. The bubbles become smaller and smaller the deeper you go. When you arise to the surface, the compressed gasses expand when  the pressure drops. Causing "The Bends" which is just air bubbles forming in different places in the body. The higher the pressure, the more the higher pressure will hold the air in compressed and absorbed suspension.
The same thing happened to the passengers and crew of the two Malaysian Airliners. The cabin pressure is maintained at about 8,000' by using high pressure compressed air from 35,000 feet and heated by the friction of the compressed air between the first compressor stages of the engine. There isn't air/oxygen at 35,000' but if you can compress enough 35.000' air to equal 8,000'.or sea level, the later stages of the engine that burn the actual fuel for thrust, will be happy. When you get into a jet passenger aircraft, your body is set for Sea Level atmospheric pressure. You become uncomfortable when you take off and you finally become comfortable. Once you get past the 8,000' or whatever elevation the crew decides they want to maintain the aircraft. If the aircraft is flying at 35,000' and rapidly decompresses, the compressed air in the body will rapidly expand. Especially in the lungs.  When the aircraft drops below the set cabin pressure, all air starts to compress to the actual altitude.

You MUST keep the pressure at the top of the system at a high enough pressure to keep from forming air bubbles. The pressure keeps gasses compressed and trapped.

Fill Valves:

@ July 17, 2014 11:24 PM in Constantly purging air in hydronic system

If you buy a Watts S1156Fbrass fill valve only, it is possible that it is a direct replacement. The union on the fill/inlet side may be the same union. If not, you will have to change just the copper union part. Because the adapter is on with Teflon tape, it will screw right off.
If the pressure gauge says 10#, it doesn't have enough pressure. You have a auto vent on the second floor. When the system is off, and not running for hours or overnight, check the pressure on the top floor. If when you open the top floor vent, water will squirt out, if it doesn't, the system pressure isn't high enough.

All lined up:

@ July 17, 2014 10:14 AM in Do I need a chimney liner?

BH,
Thanks. It would appear to me that the existing chimney is so close to being at the limit, that it is not code. There's not a lot of calculated difference in a 3 sided chimney and a 4 sided chimney,, heat loss wise. In Massachusetts, a building permit and a gas permit would be required because you are modifying the vent. Inspectors are supposed to condemn such a chimney because they banned 3 sided chimneys because you can't warm them up.
The re-liners just go by the size they can get in, not whether it is legal now to do so by the connected load.
And as far as putting in a 7" X 11" oval liner down that 40+' chimney? I'll be in the cellar, pulling on the chain to get it down, if it will come down. Someone else can feed it down from that height. And I'll watch while someone hammers into the wall to get the SS liner into the room. I just LOVE good entertainment. You'd have to stage that chimney. If the low bid was just going to set a ladder against the chimney, a 40' ladder is too short. And the leverage might knock it over.
I'd be Power Sidewall Venting the whole thing. A whole lot cheaper.

Long & Short:

@ July 17, 2014 9:49 AM in How Long

Just for thoughts because I know not about such things.
If the HX for the lake cooled water was in the return duct, before the AH, which I am assuming is a heat/AC AH, the A-Coil would provide some restriction (bad) but could collect condensation if it was forming from the cooler air stream (good). But my main point is that if you get sufficient cooling from the lake in the Spring and fall, you may not even need to run the normal AC because the lake might give you enough cooling BTU's. You could cool the whole building with the lake. How cool (no pun intended) would that be?  People put hot air duct boosters from wood stoves to heat. Why not the same with cold air?
If there are no records, trot/row out on the lake now and find out the surface temperature at the top of the lake and the bottom of the kale. It will be colder at the bottom at this time of year. In a month or so, the water temperature will be rapidly cooling. It is still colder at the bottom. When ice forms and the entire lake is covered with ice, the bottom of the lake will be 39 degrees. If it isn't, the lake isn't on the earth we live on. If you or someone does all this, you can have a pretty good idea of the amount of available cooling water in the lake loop.
If you can pull it off, they will gather at your feet for your words of wisdom after reading about your accomplishments in some Green Technology magazine.

Trust me. The Greenie Weenies have dreams at night to have the chance at a job with a big lake beside it to play with.

Air:

@ July 17, 2014 9:09 AM in Constantly purging air in hydronic system

Three years ago, you brought this up. It was suggested that you didn't have enough pressure in the system. You found that there was a "leaking" auto vent on the second floor because the floor/rug was wet. You changed the vent and the problem went away.
But you still have air. Did you increase the system pressure to a pressure that when the system is cold, that you get water squirting out of the second floor vent? Because if you didn't raise the pressure, you just put a band aid on the infection. The Infection is the lack of system pressure and the bladder/expansion probably not having enough pre-charge pressure. That Watts 1156F is as useless as boobs on a chicken. Air isn't going in through the valve, because the valve probably barely passes water. If it was disconnected, I doubt it would pass water. Or little water. That is a cast iron valve because it is painted the same color as the top. If it was a brass body valve, the body would be bare brass color. The top would be painted the same color as yours. There is a stainless steel screen on the outlet side of the valve, Because the valve is cast iron, and both ends are connected with copper tube, the screen plugs solid with iron particles. I'm not even sure that Watts sells those CI 1156's anymore. I think a lot of boilers died because of them and they did a GM key thingy. They just dropped the price of the brass valve to the CI one and the brass valve was the only valve available. Replace it with a Watts 9-11 with the backflow. Then, no one can ever suggest that water is coming in from the street with air and contaminating your system. The only possible way that can happen is of your system has a massive water leak.
In my experience, I have never seen an old cast iron Watts 1156 that would pass water.

You can doo all the expensive and time consuming work and change the fill valve, and the problem will go away. You can change the valve and the same thing will go away. And you can go to the beach instead.
I have NEVER, EVER, EVER, EVER HAD AIR APPEAR IN A SYSTEM ever IN MY LIFE, once I filled a system. As long as the system pressure was maintained high enough with the system cold, the expansion was properly sized and not too small. That #30 Extrol might need to be changed to a #60 or have a #60 added somewhere. If that is a cold start boiler/system, there isn't enough expansion room. Don't ever believe what the pressure reads on the Tridicator gauge unless you have proven it with a gauge of known accuracy. Just because it might read 15# doesn't mean it does.

Flue Size:

@ July 16, 2014 9:21 PM in Do I need a chimney liner?

BH,
I don't have any books since I moved, but I didn't know anyone (including myself) who knew how to properly size a flue/chimney for a gas appliance until I did my Comm of MA Continuing Ed class that discussed it. I doubt seriously that chimney liner "specialists" can do it properly.
From what is posted for the two boilers and an estimate that the gas storage hot water heater is about 36,000 BTU's, the total input into the flue is 221,000+/- BTU's. It is an 8" X 12" clay flue tile. I estimate the chimney to be at least 40' high.
You sit on the committees. Can you properly vent 221,000 BTU's in a 40', 8" X 12" chimney? A SS corrugated liner will at best, be 6" X 10". Can you legally (to code) vent the three appliances (total 221,000 BTU's into that sized liner?
My experience with a chimney like that is that it will look OK at the bottom and top. It is the middle that is bad and all deteriorated. If you run a chimney cleaning brush down the flue, all you will get when the brush is in the middle is sand. From the failed liner from acid corrosion.  
Just asking. Its not my house and in Florida, if it has a chimney, its fake.

Montana Water:

@ July 16, 2014 8:57 PM in GEO COOLING

If you are considering Geo-Thermal in Montana, be sure you consider the quality of the ground water, Some areas of Montana have some serious ground water quality issues that can severely effect the heat transfer abilities of the HX'ers.

Trap Debris:

@ July 16, 2014 8:50 PM in Trap on 4" sewer main in basement

Who'd a thunk.

I've been asked to open traps to look for lost earrings,  engagement and wedding rings. I've found them too.

Livin' In The Third World:

@ July 16, 2014 10:50 AM in How Long

That may be so.
I had a electronic thermometer with three test leads. You could test three things at once. Just not all at once. Where I worked, having Shade Tree mechanical abilities could be a must. I once had some ME/Rep tell me that I was incapable of changing the shaft seal on a booster pump. But he would come down with a mechanic (2 people) and change it. Minimum charge of 8 hours at $150.00 each, plus the part. I told him that unless he was born before 1943, I had probably been changing pump seals before he knew what a pump was. I changed it in 2 hours.
Engineers were the same.
In some varying form, I would have put a garden hose into a 5 gallon bucket, with my handy pump pumping in to the PE lake loop. With a 5 gallon bucket on the outlet. I would time the filling of the 5 gallon outlet bucket and determine how many GPM/GPH it was filling the bucket and computed how many # of water flowed into the bucket. I would have measured the sill cock water temperature going into the first bucket and the temperature of the water coming out of the lake to determine the differential. A third world calculation to figure out how many cooling BTU's are available. You could probably cool and de-humidify the building with the lake water for a large part of the year. Its my experience with engineers that if you have done your homework well, the engineer will take your figures, agree with your methodology, and get someone else to do the job so they can get a big cut out of the job. Leaving you watching someone else make a mess out of what you had carefully planned.

That Rep/ME? He had installed the booster pump system. The street pressure in the building going in to the pumps was 67#. It was boosted up to 135#. The whole potable water system in the public building was running at 135#, no matter what was run. The pumps were installed without a service by-pass so you could take the whole system out of the loop. With the pumps turned off, there was no pressure drop in the building and it still maintained over 60# flowing pressure THROUGH THE RESTRICTION OF THE PUMPS.
Those of us who learned to keep our tools out of the hot sun and in the shade of the tree, would never do that. That's not even code.

25#?

@ July 16, 2014 10:13 AM in Ecodrain gets US building code approval

2" Type DWV Copper? It weighs 1.07# per foot. Maximum code length for an unvented shower drain is 6' developed. A scrap dealer might give you $20 to $ 25 for it. But how much $$$ savings are you going to get from mixing 120 degree water into a shower valve that mixes it down to 106* and goes down the drain at about the same temperature as a body fluid.
The manufacturer can make any claim they want. I'd just like to see actual repeatable test results. In installed field applications.
Take that same $$$ and insulate all the hot water lines. New flow restricted shower heads. There's money well spent.
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