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TTT, teflon tape tips
Problems arise when the tape ends up inside the pipe as well as outside. We see "shards" in pumps, valves, strainers, etc.
The key is to start the tape one or two threads back from the end of the male thread. Not off the end like the right side of this nipple shown. Starting back a thread keeps it from getting inside and causing headaches.
Some plumbers put a coating of pipe dope over the tape. Some plumbers put pipe dope then teflon tape. Some plumbers tape the male thread and tread dope inside the fitting.
The tape should work fine by itself.
Different stokes for different folks.
I don't know there is a huge difference in tape color other than a visual. The stainless steel specific tape seems to have a coating of something like anti seize.
The key is to start the tape one or two threads back from the end of the male thread. Not off the end like the right side of this nipple shown. Starting back a thread keeps it from getting inside and causing headaches.
Some plumbers put a coating of pipe dope over the tape. Some plumbers put pipe dope then teflon tape. Some plumbers tape the male thread and tread dope inside the fitting.
The tape should work fine by itself.
Different stokes for different folks.
I don't know there is a huge difference in tape color other than a visual. The stainless steel specific tape seems to have a coating of something like anti seize.
hot_rod
1
Re: How does a combi boiler handle substantially higher or substantially lower DHW input water
However if you only open a tap to dribble hot water, 1 gallon per minute, you will get 140F with the boiler either modulating or cycling quickly --ok but how would you find out which. It doesn't appear in the specs that I can find.
It depends on the minimum boiler capacity: many combis can do a 10:1 ratio, so say a max of 200,000btus and a minimum of 20,000btus.So as long as the output required is above 20,000btus, it won’t cycle. It’s pretty forgiving, 1 gpm at 40 delta T is about 20,000btu.
Re: How does a combi boiler handle substantially higher or substantially lower DHW input water
It may be a little easier to realise that what is really limiting is how much heating power -- BTU per hour -- the boiler can transfer to the domestic water.
If a boiler is rated, as you note, at 3 gpm with a 77 degree F temperature rise, that means that the boiler is rated to transfer 1917 BTU per minute (about 115,000 BTUh) to the domestic water. If you have less flow, the potential delta T will be greater (although the boiler should either modulate or turn itself on and off to maintain the maximum temperature). If you have more flow, the delta T will be less. Some boilers may have a maximum flow rate throttle build into them, though I would say it is unlikely. Any combination of flow rate and delta T which works out to 640 BTU per minute will work. For example, if you have cold incoming water at, say 33, then you could either have a maximum of 2 gpm at 140 or 3 gpm at 110 -- or somewhere in between.
If a boiler is rated, as you note, at 3 gpm with a 77 degree F temperature rise, that means that the boiler is rated to transfer 1917 BTU per minute (about 115,000 BTUh) to the domestic water. If you have less flow, the potential delta T will be greater (although the boiler should either modulate or turn itself on and off to maintain the maximum temperature). If you have more flow, the delta T will be less. Some boilers may have a maximum flow rate throttle build into them, though I would say it is unlikely. Any combination of flow rate and delta T which works out to 640 BTU per minute will work. For example, if you have cold incoming water at, say 33, then you could either have a maximum of 2 gpm at 140 or 3 gpm at 110 -- or somewhere in between.
Re: How does a combi boiler handle substantially higher or substantially lower DHW input water
It is up to the engineer that specd the boiler to make sure it has enough capacity for that condition. In cold climates where you have municipal water supplies that are just above freezing in the winter that would mean cascaded or commercial boilers to get over 3 gpm or so. An indirect is almost always the more practical solution unless it is a commercial installation that has a continuous dhw demand.
When the temperature of the incoming water drops to near freezing (say 35 F) and the boiler is running at full capacity: what happens? Lower gpm? Lower temp?
mattmia2
2
Re: How does a combi boiler handle substantially higher or substantially lower DHW input water
They should all have "priority" logic. Even Indirect Tanks and Relays work like this. On a Call for Domestic HW, all hands are on deck and run to meet the demand. Circulators for the Heating zones shut off, until HW Demand is satisfied. Mad Dog 🐕It doesn't have to be that way but that is how most systems are designed. You could use an indirect with more storage capacity to let the indirect use whatever is left over from the heating zones.
mattmia2
1
Re: Code: Where is it?
Interesting, now I am curious if we have different rules here for oil lines as well, I know they require permits for any other fuel lines here
@Mad Dog_2
When you guys pull a permit for a water heater out there do they make you pull separate permits for the plumbing and the gas or electrical connection? We have to pull 2 here in my county (Plumbing and either mech/electric), and they are trying to get the rest of the inspectors in Michigan to do the same. I just figure the result is less permits pulled for water heaters lol
@Mad Dog_2
When you guys pull a permit for a water heater out there do they make you pull separate permits for the plumbing and the gas or electrical connection? We have to pull 2 here in my county (Plumbing and either mech/electric), and they are trying to get the rest of the inspectors in Michigan to do the same. I just figure the result is less permits pulled for water heaters lol
GGross
1
Re: Flame Retardant Paint for spray foam
Extremely flammable.Mad Dog_2 said:I remember the G C. Saying the spray on insulation was flammable as it sprayed on..is that a Myth or true? I DO remember it being very noxious. Mad 🐕 Dog
But it also burns pretty good after it sets up too.
ChrisJ
2
Re: Pfas / forever chemicals
Long term affects on humans is a very interesting topic.
Lead, asbestos, tobacco products, etc are all harder to link to certain illnesses than one may imagine. Some people die of cancer for no known reason while others who are exposed to the above list live well into their 90s with seemingly no ramifications.
When I lived in western Massachusetts there was widespread PCB contamination from the local General Electric plant. They made all sorts of distribution equipment and transformers. The solution to pollution is (was) dilution back then. They would dump PCBs on the soil and give it away for free for fill to spread it around. This was all above board mind you.
Come ahead a few decades and now they are paying for thousands of tons of soul to be removed and replaced....
Long term affects, need long term study. I could go into an interesting topic about that.... no one really knows what the future will bring.
I feel I agree with some of what you said, but not all of it.
I've watched quite a few friends who were smokers die from it in their 50s.
My grandfather died in his 70s, I guess he was a lucky one.
Yes, some who smoke make it into their 90s, but most do not. I think (honestly, doubt what I think matters on this topic) cancer is one of those things that, if you're going to get it, smoking makes it a lot more likely. It aggravates the situation.
Asbestos, I do not have any personal experience with anyone that had problems from it but I believe what I hear and try to avoid it. But to be honest, I also try to avoid breathing fiberglass also.
Lead, the effects are well known and have been for a very long time (hundreds of years?) and can easily be linked. There's no guessing on this one. I often use lead solder on electronics and I wash my hands after handling it.
PFAS etc I have no idea.
I'm guessing over time they will figure out more and more about it.
ChrisJ
2
Re: Flame Retardant Paint for spray foam
What is X-2? I don't like spray foam. The attic was redone in 2007 and the installer used open cell instead of closed cell and didn't install a vapor barrier. As soon as the roof gets hot, the whole attic stinks unless all the windows are wide open. I had never heard of fire retardant paint for SPF until now. I figured since it was already loaded with TCPP it wasn't needed. But then I found out that polyurethane smolders during a fire. When you add the fact that so many homes have old ionization detectors, and that these apparently do a lousy job of quickly detecting smoldering fires, you might have a real problem...Interestingly while the number of home fires, fire deaths and injuries have all declined since 1980, the death and injury rates per home fire have both increased. It seems home fires have become more lethal and dangerous.
https://nfpa.org/-/media/files/news-and-research/fire-statistics-and-reports/building-and-life-safety/oshomes.pdf
https://youtube.com/watch?v=pnlkiZC0dd0
https://smokealarmsafety.org/index.html
Here's a great collection of lab tests comparing ionization vs. photoelectric smoke alarms performance going back several decades: propertyevaluation.net/Residential%20Smoke%20Alarms%20-%20Ionization%20vs%20Photo%20-%20Various%20Reports%20and%20Presentations.PDF
Anyway, I know this was kind of off-topic. Googling around, some options for SPF I'm seeing are DC315, F10E, Contego, Firegard
https://nfpa.org/-/media/files/news-and-research/fire-statistics-and-reports/building-and-life-safety/oshomes.pdf
https://youtube.com/watch?v=pnlkiZC0dd0
https://smokealarmsafety.org/index.html
Here's a great collection of lab tests comparing ionization vs. photoelectric smoke alarms performance going back several decades: propertyevaluation.net/Residential%20Smoke%20Alarms%20-%20Ionization%20vs%20Photo%20-%20Various%20Reports%20and%20Presentations.PDF
Anyway, I know this was kind of off-topic. Googling around, some options for SPF I'm seeing are DC315, F10E, Contego, Firegard
Re: Cheap Pipe Threader???
@Rusty2 I've got a decent 6" bench vice that has teeth to hold pipe up to about 3" in diameter. Hopefully that will do the trick! And thanks for the tip on the SS hose clamp ad a cutting guide!
My original plan was to swap a metal blade onto an older cheaper miter saw for the rest of its days...
My original plan was to swap a metal blade onto an older cheaper miter saw for the rest of its days...
