Joined on January 19, 2012
Last Post on August 31, 2014
@ October 5, 2013 5:43 PM in snowmelt systemThe 667 can be set to limit the difference between the supply and return delta t on the snowmelt. You can effectively limit the amount of energy the snowmelt can use.
@ October 5, 2013 5:00 PM in snowmelt systemPaul,
The attached manual has great design info.
You are going to face some challenges with the Navien option.
When snowmelt systems fire up they will take all the energy you throw at it.
If you connect to a heating system you have to limit how much it can take.
The tekmar 667 is expensive but works well in these situations.
Personally, I would use a triangle tube boiler for the snowmelt and not use a heat exchanger at all.
@ October 3, 2013 4:52 PM in Great ArticleUnless you are using indirects with a very wimpy exchanger (amtrol)., I really have never seen this problem. Using Smart and Heatflo indirects the boiler can generally come up to full fire and run 10 minutes or so, satisfy the load and shut down. There is plenty of room for the boiler to modulate down if needed. Alpine boilers are not common here, maybe they have an issue I have not seen.
@ October 3, 2013 2:20 PM in Mixing Cast Iron with radiant panels, matching tempsI like it.
If you are confident in your design temp, just size your panels to match the heat loss at that temp. Uponer has charts for all that. http://www.uponor-usa.com/misc/cdam-request-page/default.aspx
The section you want is toward the end.
If you cannot get the tubing tight enough you could either do a wall panel or as you suggest, run the radiators a little hot.
@ October 3, 2013 9:09 AM in ft head lossPaul,
Once you find your BTU loss per square foot of you project, use this manual to figure out the rest.
If you start around page 270 you can figure out the water temp required for your assembly, floor covering and required heat output. Then you can go down and figure the flow requirements. Once you have your flow requirements you can calculate the head loss.
@ October 2, 2013 9:26 PM in TT110 Trimax control questionWith that configuration the 8" would be on the right.
Set the circulator to speed one.
@ October 2, 2013 3:23 PM in TT110 Trimax control questionThe boiler supply should be on the left
@ October 2, 2013 3:21 PM in reset controlHow low are you trying to go? You could put a simple reset controller on the boiler, but you cannot lower it to where it will condense. The lowest would be around 150. If you want to go lower you need a condensing boiler or a mixing loop.
Either way, the nest is controlling the room temp and a separate controller is doing the outdoor reset.
@ October 2, 2013 3:15 PM in ft head lossPaul,
The head loss for any piping system is a curve. It will vary based on a number of factors.
The temperature and percentage of glycol are minor factors.
The length of the pipe and the amount of GPM you are trying to push is a huge factor.
There are some vary long formulas in 'Siggy's books that will allow you to get these numbers right on.
Uphoner has already done the math and have published tables to make it easy.
I found the 3.22 on the Uphoner tables..
Your formula will give you a rough idea of the head loss through copper pipe based on 4 ft per second. Pex has a different inside diameter and coefficient. Not to mention you would need a huge circulator to push 4 ft per second through a 200' radiant loop.
@ October 2, 2013 1:12 PM in ft head lossPaul,
I think these charts from Uphoner will help you out. http://www.uponorpro.com/~/media/Extranet/Files/manuals/PressureLossTables_H191_1210.aspx?sc_lang=en
Your design for infloor radiant will not have to be 1.5 gpm. Most systems will run just fine with .7-1.0 gpm.
If you look up 1/2" pex at 1 gpm at 140 degrees you get 3.22' per 100.
A system with 5-200' loops will need 3.22x2 =6.44 feet of head. Since you have 5 loops you will be shopping for a circulator that will push 5 gpm at 6.44 feet of head. if you have significant feeder lines or boiler room piping you need to figure that in as well.
Taco flow pro university does a great job of explaining this.
@ October 2, 2013 12:19 PM in TT110 Trimax control questionThat will also work. It looks like the supply and return are backwards in that drawing.
@ October 2, 2013 12:00 PM in reset controlWhat type of boiler and controls are you working with?
Is the system radiant or base board? What type?
@ October 2, 2013 8:49 AM in Lochinvar Knight Hex ??I have never heard of sizing boilers that way. You should really have a heat loss done ( or do one yourself) if your existing boiler is sized correctly you will need the 85k because you derate the less for efficiencys . That is a big if. Have a heat loss done
@ October 2, 2013 8:35 AM in TT110 Trimax control questionTry to keep a minimum straight pipe of 8" to the left and 4" to the right of the setup you have drawn.
@ October 1, 2013 10:54 PM in TT110 Trimax control questionThat will work. The flow through the primary is counterclockwise, yes?
@ October 1, 2013 7:53 PM in TT110 Trimax control questionIf you connect the boiler pipes to create a loop and tie the manifolds into it using closely spaced tees, you will have primary/secondary.You will want to make the connection on a straight section of pipe. It looks like under the boiler would work well.
@ September 30, 2013 9:54 PM in Converting to two zonesThe zone valve is a motor that then trips a switch.
The yellow wires are the motor and the red ones are the switch.
I don't know why Honeywell needs to make it so confusing.
The above directions will work.
@ September 30, 2013 5:30 PM in Converting to two zonesThe wiring diagram in the manual is about the ugliest thing ever. Page 5 is what you are trying to accomplish. http://s3.pexsupply.com/manuals/1350895801607/84105_PROD_FILE.pdf
If you connect a red from each valve to the "T" terminal and the other 2 red wires to the "TV" terminal, that will take care of the red wires.
A yellow from each valve should go to "Z"
The other yellow's go to their respective t-stats. The commons from the t-stats need to come back to TV.
It would be cleaner to either do as Paul S recommended or use a Taco zone controller.
@ September 26, 2013 9:58 AM in How to find a leakIn the somewhat unlikely event the boiler's heat exchanger has a leak, the water will end up in the condensate line. The normal condensate comes from the combustion.
@ September 26, 2013 9:43 AM in How to find a leakIt is supposed to drip when firing, Especially at lower temps.
If you have a cold (off) boiler with a steady drip, that is a problem.
@ September 26, 2013 9:09 AM in burnham steam boiler pressure issueI think you were correct to install the new pigtail and pressuretrol. Since you were not scalded when you unscrewed the pigtail, I am thinking you don't have 10# of steam in the system when cold. I think your new gauge is measuring about 1# and is accurate.
The system you are working on is an ancient art. It is not like most intuitive mechanical projects you have likely encountered. I think you should stop what you are doing and read "the lost art of steam heating" available on this site. Once you have read the book you will understand the nature of your heating system.
@ September 26, 2013 8:53 AM in Boiler is piped to elec..water tank is that ok?So, you have a propane boiler, an oil boiler and an electric water heater all as heat sources?
How in the world is this mess plumbed?
The only reason I can see for the water heater is they may be using it as a buffer tank for the oversized boilers, to keep them from short cycling.
You are correct about the expansion tank.
I would start with a heat loss calculation on the home. This is going to tell you how oversized your heat sources are and help you make some decisions. To give you an idea, your heat loss is likely in the 30-40K/BTU range.
Maybe you should draw out how this mess is piped so it is more clear how to deal with it.