Joined on January 19, 2012
Last Post on December 4, 2013
@ December 4, 2013 11:34 PM in Taco Bumblebee CirculatorHere is the manual.
How are you using it. What mode is it in? Sensor?
@ December 4, 2013 3:49 PM in Lochinvar Knight - single pump, 3 zone systemTraditionally we use bipass valves to prevent deadheading circs and to keep the system at a constant pressure. This use has been replaced with delta p circs.
The lochinvar drawing for a single pump system is using it to maintain minimum flows through the boiler as well.
@ December 4, 2013 9:34 AM in Lochinvar Knight - single pump, 3 zone systemNotice that lochinvar shows a diff bipass in the drawing. This assures the minimurm flow through the boiler.
If you did an accurate head loss and could assure the flow,one pump could work. With 300 foot loops, I have concerns.
I don't use auto adapt with the grundfos alpha. It is really designed for systems that are always pumping. It will not work at all in on/off applications.I know people who leave it on with closed zone valves, I don't know why.
For 300 foot loops constant pressure 3 would be a starting point.
The strainer won't hurt.
@ December 4, 2013 1:10 AM in Lochinvar Knight - single pump, 3 zone systemI believe you can do all this as a single temp system.
Why are you so reluctant to use an alpha(or similar delta p circ) with zone valves for the system side and the 15-58 for the boiler side?
Why do you keep going back to 4 pumps or one pump?
The answer is 2 pumps, primary/secondary.
I would be very reluctant to do a non primary/secondary with 300 foot pex loops.
I don't see the need for a strainer on a new pex system. What are you straining?
This is the most common setup for a reason. It is simple and it works. Don't reinvent it.
@ December 3, 2013 9:12 AM in Slow leak at joint (picture)This guy is a "one post wonder" from 2 1/2 months ago
This problem was solved months ago with some sharkbites and a scrap piece of garden hose.
Maybe you guys should debate something more productive.
How about cheerios vs corn flakes?
@ December 3, 2013 8:32 AM in Pressure relief valveThe relief valve on the water heater is for the domestic water and is independent of the the boiler 's water and expansion tank.
Do you have a domestic water expansion tank?
You usually need one if your domestic water system has a check valve at the meter.
@ December 3, 2013 8:25 AM in Best thermostats for 10 zone systemYour boiler will run at peak efficiency if you set up the outdoor reset. The most efficient outdoor reset curve will use the coldest water temp possible. Colder water makes heat system respond to changes in thermostat settings very slowly.
Outdoor reset and thermostats that are constantly changing the room temps do not work well together. The reaction time is too slow for to recover from a temp setback.
Over zoning houses tend to make the boiler short cycle. This decreases overall efficiency. 10 zones are not more efficient.
I think you have two choices:
Install 10 very fancy t-stats and leave the the boiler set at a fixed high (inefficient) Temperature. This will give you the feeling that you are saving money, in reality you wont.
Install 10 or less (grouping zones together) simple non programmable t-stats and set the boiler at the lowest possible temps via outdoor reset. Do not change the settings. just set it where it is comfortable.This approach is very boring, but you will be more comfortable and will save more money.
If you decide to spend a bunch of money fussing with the indoor temperatures, look into a product with indoor feed back like the tekmar whole house controller. It will do what you want with the indoor temps and still keep some efficiency of the modulating boiler.
Keep in mind that every time you change the indoor temp, you are not just heating the air. You are raising the temp of the entire mass of the house. It takes significant energy to do this.
@ December 2, 2013 11:40 PM in Putting system together - pump selection helpHot Rod is right on the money on the ecms.
On your radiant side, check out these design manuals from uponer https://www.uponorpro.com/Technical-Support/Manuals.aspx
If you design your panels to run at approximately the same temp, just run a single ecm delta p circulator and zone valves with one temperature curve and voila,you have a simple, comfortable system. Keep it simple!
If you take a circ like the alpha and set it to constant pressure mode, you will always have the correct flow of water using the least amount electricity.
Taco is a fine company. They just don't have the best product for your application.
@ December 2, 2013 4:45 PM in Putting system together - pump selection helpYou should be able to do an accurate heat loss on your other floors. It would make your boiler sizing a bit more accurate. My guess is that the 155 is a bit big and the 110 a bit small. The point may be moot.
You absolutely want to pipe primary/secondary per the manual.
As for circulators, the boiler circ should not be a 26-99. A grundfos 15-58 or taco 007 is more than enough. More is not better with mod/cons.
For the secondary, I have great luck with the grundfos alpha with zone valves and radiant.
The Alpha is a delta p ecm circ that has a nice curve for most radiant systems.
The curve on the 007 is a bit flat for radiant applications.
If you are doing an indirect, It wants to be priority with it's own circ.
@ December 1, 2013 11:18 PM in Ideal pex routing for underfloor install?As for drilling the holes, your chart is correct. The reason for the 2" from the edge has to do with tension and compression within a structural members. That is a longer story.
1 3/8" holes work well because the "buttholes" or "squeakers" as weezbo calls them are made for 1 3/8" holes.
The first picture you posted is the best and easiest way to do this. Not only will your second idea not make any noticeable difference, it would be an absolute pain to do it that way.
If I was looking to over think this, I would do a heat loss calc and then increase the concentration of plates in strategic areas. If you have a noticeable difference in temperature, it will be related to variations in heat loss from one are to another, not unevenness do to tubing layout. With the options you are looking at, the center of the house will feel warmer than the perimeter. To your feet it will all feel the same.
@ November 30, 2013 11:29 PM in snow meltThe 667 will give you more control. You can provide boiler protection and restrict the delta t to the snowmelt. This insures that the house will get it's share.
What Steve is suggesting would work better with a 665. I agree with his point about freezing the exchanger. Oops!
@ November 30, 2013 11:06 AM in One Pipe Boiler System to A Two PipeI agree that this sounds like a mono flow system.
If your monoflow is working, leave it alone. Most folks have trouble with monoflow when they attempt to modify. There is nothing inherently wrong or inefficient about monoflow.
I would be sure the outdoor reset is set up correctly, that is where the real efficiency comes from.
@ November 30, 2013 10:25 AM in Aquastat L8148E , Utica MGB75HD set tempYour boiler is a non condensing model. The return water temps should never be below 130 degrees.. Low temps will cause the acidic condensate to damage the boiler and flue pipe. This will greatly shorten the life of the components and potentially cause a CO leak.
The aquastat should be set somewhere between 150 and 180 degrees depending on your requirements.
@ November 30, 2013 10:18 AM in Up to 30 minute delay after furnace and thermostat clicks onIt sounds like the furnace is having trouble with ignition.
It would be a good idea to have it serviced sooner than later.At some point it will not ignite at all leaving you chilly.
@ November 30, 2013 9:26 AM in Need advice- open radiant systemUnfortunately this type of system is legal in most areas.
Legionella and other water born illnesses are rarely tested for for in this country , it is no surprise that they don't find many cases. Pneumonia is very common , it presents itself just like legionella. It always amazes me how many hospital acquired cases there are yet no testing. Countries that do test have much tighter standards.
To answer your questions.
A heat exchanger and associated piping will solve your water quality issue. You will not lose performance or efficiency.
Your builder did "cheap out" on the heat system. You have an appliance designed to heat domestic water heating your house. I am surprised it has lasted this long.
@ November 29, 2013 8:52 PM in Maximizing efficiency of a mod con questionVery nice post. You are way ahead of the game.
Very few contractors understand most of what you have posted and even fewer care enough to chase the last couple percentages of efficiency.
Here is an interesting read if you haven't seen it yet.
Notice that tuning the boiler for optimal CO2 is also very important.
In a perfect world, the boiler manufactures would design an appropriate circulator (I don't believe it exists) for your fire tube boiler and control it with variable speed. Don't hold your breath.
Bypassing your primary secondary should work just fine. You could even slow down the secondary flows and get a wider delta t.
@ November 29, 2013 11:28 AM in want feedback piping WOOD boiler gas mod/con backup via reverse indirect BUFFER tankYou really have a great start.
A couple thoughts...
How often will you use the backup boiler? It would be nice if it could run at low fire during a radiant load. Much more efficient. A properly sized fire tube mod con does not need a buffer.
Another way to do it would be to set up the wood boiler storage tanks as boiler one and the mod con as boiler 2. They could be piped in parallel to a common header. A tekmar 2 modulating boiler controller could control a 0-10 vdc circulator between the wood boiler storage tanks and the common header.
Do not use smart tanks for reverse indirect. They are carbon steel on the outside.
@ November 27, 2013 8:52 AM in Hot water helpYou are certain that you do not have a tankless coil on the boiler that preheats the hot water? That would explain the problem?
What temp is the water heater set?
I assume you do not have a thermostatic mixing valve? That would fix it.
@ November 27, 2013 8:38 AM in Delta t ?The correct way to do it is with the right size circulator or flow control valves.People do what you are doing all the time, It is not that big a deal.
@ November 27, 2013 8:33 AM in Taco wiring questionSorry I mis-read your post. At .3 the controller must not be working at all. Are you checking from hot to common or hot to ground?
@ November 26, 2013 9:13 AM in Taco wiring questionI don't think the transformer or board were damaged. This is not the first time one was wired backwards.
23.3 is a little low. What does the 120 volt circuit on the line side measure? If it is also a bit low, you don't have a malfunction.
You need to see if the on board transformer has enough va's to run your zone valves.
It sounds like this will work, you may need to set another transformer for the valves.