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starcat

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starcat last won the day on November 27 2019

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  1. I have combined 30 years experience dealing with HVACR, Steam, and Propane fired systems. I have never gotten into any cost estimation with propane, but I can tell you its both expensive and more dangerous to run than NG. When doing certain types of burner setup and testing with NG, it is common sometimes to get a clock on the gas meter to estimate cubic feet. Your consumption figures need to be accurate or you may be shocked with actuals. .https://homeguides.sfgate.com/determine-propane-burn-rate-furnace-25507.html If its possible for thw size boiler you are getting, you need it equipped with a full modulating fire burner. This will save both fuel and duty cycles on the ignition, and gas train system. Propane is a dangerous affair, and while I have run it exclusively on one remote property, I do not care for it. The fact that is is heavier than air changes a major lot in a Technicians approach. Any shade tree or cut corner maneuvers will get you in trouble, double quick. Some of these types of situations are out there ticking like time bombs right now. There are a number of good boiler threads on this forum which should be read.
  2. The Average Residence built in modern times will have a 200 AMP 1PH service. I would not want to run commercial on less than 400A-3PH, and again it depends on your loads. While you may need an Electricians assistance to properly fill out a load sheet for your space, this process is an education. It requires you be very detailed on everything that is going to be run or could be run with the existing plan down to the watt. Its a Painstaking affair. It requires nameplate data on everything in order for the calcs to be accurate. There are averages and rules of thumb for certain types of loads. Service upgrades can be expensive, and modern requirements are much more on the POCO end of things than they were in the past, and they want the customer to absorb much of that cost. Even having been in HVACR-Electrical systems work for 30 years, the task is still not fun for a large property and I have done it more than once.
  3. The AHJ can tell you what they want to see for sure, but both they and the GC are going to tell you you need an Engineers stamp to proceed. Getting a really good set of architectural drawings which include all aspects of the build out for this craft can be challenging. In order to get the best possible result, you need some expertise in your camp that ideally is very well versed in Industrial Electrical-Mechanical systems. This will help both raise the correct questions and get you the system that is going to work the best for your needs. For sure it will be helpful to visit working production facilities of a similar size and scope that are well done.
  4. You need the Goulds NPE series for plant water recirculation. When correctly sized and installed they are rugged, and also easy to repair when needed.An example would be model 1ST1G5A4. This is what we use for HW supply in the Brewhouse.You need a bypass valve on the discharge line, so you can leave the pump run during the shift when needed. This can be manual or automatic mechanical style as made by " Watts." You may not need a pump this big. A pump guy can help you size it. These are the best pumps for both water and glycol duty.
  5. Again, the watchman receivers are fine units to use for their intended purpose. They are not meant to return directly to the boiler with the supplied controls, although you will see many boilers in the field set up this way, this is fully incorrect and will cause the " Normal Operating Water Level " of the boiler to swing too wide, and can cause some other failures which are beyond the scope of this discussion. You can custom fit a receiver to become a return station and get rid of an extra piece of equipment for smaller systems. The Boiler is supposed to control the return water pumps in every case. if you have only a receiver and you are allowing it to control the return water pumps by action of the supplied float switch, your system is misconfigured. The sequence of operation goes like this: The Boiler commands the action of the return pumps. Low water level in the " Return Station " commands introduction of fresh water + chemicals. Its that simple. For the systems that are set up backwards as I am describing, the float switch in the receiver is controlling the return water pumps and the low level contact on the boiler is controlling fresh water infeed. This is the wrong way around, and is a hack job way to roll. The contacts on those float switches and motors are not explosion proof unless you buy a rig that is EP rated and set up as such with rigid conduit. The Modified Weinmann receiver I have shown has the stock inlet at about 10-1/4" off the floor which is reasonable. The condensate outlets being set so low on OEM devices is whats at issue and needs to be met by a response on both sides to optimize things.
  6. https://www.industrialcontrolsonline.com/training/online/your-go-guide-steam-traps
  7. While you are likely good with this choice, here is a Tech paper dealing with Steam Trap sizing and what to be aware of. You are dealing with capacities. http://www.interflow-th.com/information_Product(more)/Technical/best practices no.25.pdf As an aside, I like Spirax products and its always a good idea to have a spare FT head and gasket in your parts stock. That assembly has a heavy dudty cycle and a limited service life.
  8. The watchman unit noted is simplex and redundancy is needed as in 2 pumps. When a single pump system fails, you are DOWN. This requires that you have a receiver AND a return station which is an extra expense and an extra point of failure when both can be done in one package as I have shown for small systems. Receivers are not controlled in the same way return stations are. They are set up differently. You also need isolation capability on each pump [both electrical and mechanical] of a duplex unit so you can run on one if you have to. The best thing is to get the OEMs and return station-receiver builders into some kind of accord on dimensions that are practical in the field which would not really be that hard as I have also shown working with Silver State Stainless on recent projects. They were happy to build to a higher outlet dimension with no problems at all. It just has to be asked for. The simpler things can be kept, the more reliable they will be. Redundancy is just as it sounds and Mechanics like it six ways to Sunday. For sure it can be done as you are describing, but this would not be my choice or recommendation.
  9. Here is an example of a " lowboy " return station with the inlet listed as 16" off the floor. 16 Inches being still too high in my view: https://fabtekaero.com/wp-content/uploads/2013/08/Condensate-Return-Tank-25-Gal-SS-Duplex-Pump.pdf If the geometries are too far out of line you can flood your steam jackets to that level. The thing to do as has been noted, is either custom fit OR possibly get one of these OEMs such as Fabtek to work with you as a " Systems Builder " to design a return station that works, and works well under dimensional limits. If you notice the Blue Weinmann receiver I posted above, we are entering at the bottom which is about 1.5" off the floor. While this is not ideal, its better than keeping the entire condensate run flooded back to the still and then some. In this case the return line will only flood back to whatever the current tank level is running in the sightglass on the pump side so there is still fall from the source into the tank. The bad thing is that line is flooded on the off cycle. Its very easy and straightforward to refit this type of receiver to be a full blown return station.
  10. The centerline of our pot outlet ended up at about 9.5" off the floor which is, so down low man. I had to use a Spirax FTI trap which has outlet at same height as inlet to deal with this. We are dealing with a Still Dragon rig. The problem is too many return stations have the inlets too high off the floor. This outfit " Fabtek " has some interesting SS units and a low boy advertized, but currently without details on the websight: https://fabtekaero.com/ The inlet on the receiver I bought is at 10.5", so we came in the bottom. So again you can turn a receiver into a lowboy condensate return with a few simple MODs. Back to flash separators. I am definitely not knocking them. They are good if you have the latitude and space to install them. See 2018 UMC 1001.4 for details. If you are blowing down into a floor sink, you can run cold water from another source during blowdown to moderate things.
  11. I posted a link about blowdown separators above. They don't do much of anything on small systems really. We did not have a single one on the College campus I managed for Texas A&M. They are more about modern codes and whatever control trips the local inspectors are into. Most Micro Breweries and Small Distilleries discharge into a separator tank of fairly large size. This is a buffer zone.
  12. There are several ways to heat water for plant usage, all of which I have worked with. They are HLT system.Shell and Tube HX with pump, which can be ported to an insulated vessel in a number of ways. I have also run tanks that have tube bundles integrated, so you have steam tubes surrounded by a pressure tank as in a big hot water heater, heated by steam. Sure Store makes vertical units that are HW to HW, and I am sure someone makes one for Steam to HW. We had some big horizontal old school ones at A&M. A properly configured condensate return station is really needed for ALL Steam boilers. In our case you can see I have custom fitted a receiver with all necessary controls and essentially turned it into a " Return Station." This is for several reasons, but mainly because of the way low down entry point due to having insufficient fall from the still. It should also be noted and this has been mentioned before that the condensate outlets on a major lot of this gear are set way too low to the floor, and this is a problem. Even the smallest receivers generally are entered around 10-12" off the floor. This means you lowest condensate outlet needs to be higher than this dimension, or you will be forced to enter the bottom of the receiver which is not ideal. The OEMs need to start thinking about minimum heights to achieve gravity flow into a receiver under typical setups on a single floor level. Your really need to return all of your condensate except for blowdown to the system. I pointed this out to one of our OEMs and he made a very good adjustment on the last piece of gear we had to replace. The return station is integrated with your Fresh Water makeup, and your chemical feed.
  13. SH, thanks sincerely. This forum is a great resource. I am just the Mechanic. The Still man is Jeff.
  14. All Steam Boilers need chemical treatment, and not just for the boiler but often times you are treating the steam which treats the condensate return system. Corrosion of the return system is very common which can accelerate corrosion in the Boiler proper. This is typically done with neutralizing amines, but filming amines may be indicated as well.This is especially critical on intermittently run systems. I would want to be educated on their logic from all points to understand why they would say no treatment is needed with respect to their design and whatever the local water profile may be. In Texas as an example, we were dealing with very difficult hard water. The spring source here in Utah is about 500x better in this respect. I cannot imagine how no oxygen scaveneger or adjustment of the condensate ph would not be needed, but I am willing to listen to the MFG's explanation on the matter. Water needs to be at 170F or above to keep dissolved oxygen moderated.
  15. Blowdown separators are more about what the local inspector requires, and may be unnecessary on smaller boilers. We do not use them. https://www.maddenmfg.com/blog/What-does-blow-down-separator-do.cfm Both the brands look decent. The Sellers being a one pass Firetube design is interesting. I prefer the Scotch Marine Firetube boiler to any other design in terms of long term ruggedness and reliability. There are a lot of good ones out there. I do not care for Cleaver Brooks in the least and they have been one of the most problem laden brands I have ever worked on. Same with Hurst, which is another brand I'll never run again. For 60 HP I would definitely go with a Scotch Boiler. This guy has some good resources: BrewingwithSteam.com . I have seen a good many systems in the field which are not set up correctly with respect to how the feedwater and condensate return are handled. its important to realize that things can seem to work in these instances, but they are not working correctly and in some cases it can get dangerous. You are much better off in terms of controlling corrosion if you can keep your system active 24-7. The best way to do this is to use it to heat water for all you hot water needs. If you are shutting down all the time and going cold this will present a challenge on your chemical treatment that can be difficult to solve. All Steam Boilers require chemical treatment and daily blowdown. If you have never run steam before its a real good idea to take at least one class, and do some serious reading about what not to do with steam boilers. They can become very dangerous in the wrong hands very quickly. A duplex return station with isolation capability gives you redundancy and is 100x better than a single pump system because of this one simple fact. A major lot os steam loaded equipment is designed with the condensate outlets too low. Ideally you need to port condensate into the return station in the top of the vessel. I have brought this fact one one MFG's attention and he is making corrections. Fully modulating fire control is best. This is an example of a return station set up pretty well out of the box: https://fabtekaero.com/condensate-units/
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