If you think about it an Outdoor boiler reset controller uses a great 30 year old technology which was ok when oil was cheap, like .28 cents a gallon. If folks want to get their money's worth from that 3.25 gallon they should think about a controller that gives comfort first at the least expense for gas or oil. This can only be achieved from an indoor reset technology.

 

Could you explain how it works in detail?

 

I'd like to hear it too... as long as there are no commercial advertisements involved!

 

I did a Google search on Exqheat. It looks to be a small, possibly one-man, operation in Pleasantville, NY.

Conventional outdoor reset is essentially an outdoor temperature sensor that increases the hot-water boiler temp when the weather is cold, and vice-versa, right?

The Exqheat idea, as I understand it, is to monitor the frequency/duration (duty cycle) of thermostat calls for heat. If they are frequent or long duration (high duty cycle), then the system would increase the water temp, and vice versa.

The claimed advantage of this idea is that the thermostat's heat-call duty cycle reflects the current heat loss from the building - due to all factors, e.g., outside temp, infiltration, solar input, etc.

Theoretically, I think it might be an effective idea. But, I think implementation might take a bit of tinkering. The website shows pictures of a solid-stage controller board that gets tied into the thermostat. No price is given - just an e-mail address.

Personally, with my present system, I'm not much interested in either a conventional outdoor setback or the Exqheat. I'm content to adjust my aquastat manually.
Doug

 

Kinda' like a Beckett/Intellicon Heat Manager/HW+

No thanks, I'll keep my ODR.

Al.

 

Don't blow off this idea without checking it out. This is a good product. I have talked to them in person and learned about this about 1.5 - 2 years ago.
Here is the link.
Exquisite Heat

 

The Intellicon system seems to work on the same principle as the Exqheat: biasing the hot water temp based on the demand for heat: intelliCon-HW

The Exqheat system uses the thermostat duty cycle. The Itellicon system measures supply and return temp of the circulating water - the temp difference corresponds to the heat transfer to the house.

I think either approach could work satisfactorily. (But, as I previously said, I'm personally not in the market for a setback system for my boiler, including a conventional outdoor setback.)
Doug

 

Not 'zackly Doug... The Intellicon measures the RATE OF CHANGE of the supply temp from the boiler, and won't do a THING if the boiler never reaches HIGH LIMIT. It is very basically what I call an 'adaptive differential' technology. All it does is change the differential in response to what it perceives to be more, or less, 'load' on the system.

I don't have PowerPoint on this old machine, but am going to check out exquisite's idea. I believe that looking at the duty cycles is probably a much better approach to an easy to use, easy to install and configure product.

ODR is not a product for the masses... there are LOTS of adjustments that need to be understood and adjusted to get the things working properly. Dare I say that most heating techs probably don't have a grasp of the concept, let alone a homeowner.

Intellidyne is on the right track with their 'plug and play' design, but I don't feel that their control concept goes far enough. In the warmer shoulder seasons, there's NO reason to NOT reduce the temperature of the high limit, and the Intellidyne will NOT do it. It appears as if the EXQ WILL. Needs further research.

Just a word of caution though, let's try to keep this whole discussion INFORMATIONAL, and NON-COMMERCIAL if we can.

 

I looked at the ExquisiteHeat site although like Trooper I don't have PowerPoint on this computer. I tried to look past all the advertising but I will say that I am impressed with the concept. The nice thing about the control module is that it doesn't require any fancy thermostats or wiring.

I don't have the slightest idea of what the cost of this module may be or if it is "user friendly" enough that a typical DIYer could install it and get it working correctly. I noticed it does have an RS-232 port and I suspect that is for programming purposes and/or remote monitoring.

So while I do endorse the concept of time-based heat cycling to adjust the output temperature of the boiler I wonder how cost effective it may be in the real world and especially in DIY installations. If the cost is such that it takes twenty years to recover the initial investment I think that the "old-fashioned" outdoor reset is probably a better choice.

 

Microsoft offers a free powerpoint viewer. (Allows you to view ppt files, but not create them.)

Download Here:

Download details: PowerPoint Viewer 2007

Doug

 

According to the Exquisite Heat web site it does need a supply pipe temperature sensor. It also requires a laptop (or PC?) for set up. The menuing system looks like an old DOS program (see the pdf's on the "How it Works" menu), not sure why that is. And how many laptops come with a serial port any more?

I don't like buying into something new that isn't using new technology. Such as a Windows interface and a USB port.

Here is the blurb from the PPT on set up (under the "Detailed Theory" menu):

* Program system variables.
* Revisit until satisfied with installation settings

So it has the same curve programming requirements as does an ODR. Check out the "see the data" pdf for more on that.

It also works on one zone. Multiple zones are handled by using the thermostat of the coldest zone (from the PPT).

From the PPT:

* Savings on fuels can range from 5-30%

A wide range. So even they admit that an already properly engineered system is not going to save all that much.

If the over-sized boiler here was still banging off the 185* F high-limit with the original Arco-Flame burner, my guess it that it would save a bunch. But with the ODR, flame-retention burner, and constant circulation... well, we had the least oil consumption Winter ever. About a 33% reduction over the past years average.

All-in-all it looks like a nifty device. But it isn't an install and forget type of unit.

Al.

 

The control is factory set. See programing page on web site. Those who have a laptop can change menu items on the job if needed, with USB,

There are no curves. If you study the Power Points the formula is clearly described as it is in the patent.

You should look at the building pictures page to study the applications made to steam and hot water buildings, with single and multi zones. The thermostat used for analysis is chosen by the installer. It is easily chosen and hooked up on the low side of the zone relay. We suggest a zone which is average to chillier than average. These are seldom set back.. With the 40% margin for error in the building and hour to hour the building has the ability to adjust comfort at all zones with the adjusted high limit with in the hour. We do not experience any comfort disruption over an hours time. Heat loss in relation to change in outdoor temperature takes several hours to take effect. That is why ODR are imprecise and out of favor due to difficulty to adjust to a building.

Wisdom is knowing what you don't know and having the courage to ask a question. The first part is most difficult. The second part is more difficult.

Serial port adapters work well and are available.

You are absolutely correct when talking about the difference in savings. Every building has its own relationship with its heating system. They all have different heat loss characteristics. Nice thing about Exqheat is that way the system adjusts to all factors. If you replace the windows or insulate the change shows up at the thermostat. If you insulate the piping, it shows up at the thermostat.

Did you know that every building has different heat loss characteristics under all changing conditions. The ODR curve is almost impossible to please. That is why most ODR systems now come with an indoor corrector. The reason for that is the manufacturers are trying to mimic the results of Exqheat without infringing.

"But it isn't an install and forget type of unit." You bet. The visits are to be sure the boiler guy turned it back on after he turned it off for no reason. Any one in the control business should know that you should visit the control twice a year to be sure "broom handle" didn't try to monkey with it. Yu will also notice no push buttons for "Broom Handle" to touch.

Customers know to check the unit periodically. If the lights do what they are supposed to do all is well. If there is a problem call for service on the sticker. Most of the time the customer simply puts the switch on that some expert turned off.



Thank you

 

Umm, I'll disagree. One example that comes to mind is tekmar. They've been around for over 45 years, and went big-time in the early 1980s. Their controls have had two-way communication (e.g., indoor feedback) for at least 10-15 years. I believe your patent is ~2001.

That said, however, I wholeheartedly agree that indoor reset/feedback or whatever you want to call it is a very, very efficient way to control a building for comfort and savings. It is great that this principle, which has long been available for large buildings using things like DDC and its predecessors, is available on a residential scale. Yours is one way to solve the indoor feedback problem. There are many others. Doubtless some approaches will work better in some applications than others.

 

"...tekmar. They've been around for over 45 years, and went big-time in the early 1980s. Their controls have had two-way communication (e.g., indoor feedback) for at least 10-15 years..."

The tecmar is the one that is standard here. Guys even use it on Viessmann because it costs so much less than the Viessmann control.

The Beckett website has a simple video to show how their indoor works.

Since the Beckett/Intellicon at half the price, only controls burner time not water temp as does the tecmar, I wonder what would happen if you used both?? Never heard of anyone trying it.
The Beckett claims 13% average fuel savings. My distributor of both Teckmar and Intellicon says that the indoor averages more like 5% so he recommends Tecmar.

 

I have used both on several jobs. These were cast iron boilers and the Tekmar was doing the system reset. The boiler was short cycling due to the Tekmar controlling the system temperature. The Beckett Heat Manager when installed was controlling the boiler cycle by controlling the differential. You must first determine if the boiler is hitting limit as the Heat Manager works off the boiler limit.
The savings increased on the one in particular by about 14%. Do not know the fuel savings of the others.

 

rbeck's point is a very important one!

Anyone considering using a heat manager on their system must first determine that the boiler hits it's high limit on nearly every cycle before the heat call is satisfied. If the system does NOT hit the high limit, the Heat Manager will do NOTHING. The programming in the HM is designed that way, it's cast in silicon, can't change it.

What this means is that if your home is 'over-radiated', meaning that a heat call can be satisfied with, for example, 160° water, OR, during MOST of the heating season when the thermostat satisfies and ends the heat call before the boiler hits High Limit, the Heat Manager (or the Intellicon) will NOT 'economize' the least little bit. The red LED on the HM will stay on during every heat call.

If using ODR or EXQ in conjunction with HM, you won't see the HM help at all whenever the other control targets a temp that is less than the high limit.

 

Kind of neat. It is good to hear some feedback on Intellicon. I could never figure out what it did. I still can't see where it saves much. Your still going to high limit in April and September?

Combining Tekmar with Intellicon seems antagonistic.

If you circulate the water 60% of the time you will need a lower temperature. That must mean that the going to high limit is causing either poor comfort delivery or everyone is slipping around in their undies sliding in their own sweat.

If you deliver high limits on a less than design degree day, you have a problem. Granted if you adjust the low limit or increase and decrease the differential you will have a different mean temperature. What will that do to comfort in a multi zone system. WoW.

So what can Tekmar do for that??

 

I don't even hit high limit at the end of January!

The situations that I see the HM working well would be with a huge oversize high mass boiler, and a drafty old house with leaky windows and doors, and relatively under-radiated rooms. In such a case, the boiler would fire up to high limit quickly, the heat loss in the home wouldn't satisfy the t'stat quickly, THEN the HM would cut off the burner and extend the diff to like 30-35 degrees, and suck the latent heat out of the boiler, only firing the burner again at around 145°. In such a scenario, it would probably save... it's a 'band-aid' for a poor installation, in a leaky home.

I haven't thought about it a lot, but I suspect that some of the commercial systems might benefit also.

There _IS_ something to be said for 'slipping around...' but we're gonna keep it clean!

 

I agree. There are several options to achieve the desired result.

Since discovering the benefits of the tekmar controls with an indoor sensor (either with the indoor sensor, or the fancier two-way communicating thermostats), I've become quite an advocate for including indoor feedback with their controls.

In that situation, the control tunes all the parameters -- differential, high, low, etc. to achieve constant circulation tuned to the actual building heat loss. Works great.

 

Indoor reset is all you need. The thermostat provides all the information for the precise analysis, and adjustment of output and assures sufficient circulation for even comfort.

 

I am still confused.
First, I do often see the boiler reach high limit. With a low mass, cold start boiler that is designed to come up to temp quickly it regularly hits the limit.
One problem I have with the L8148A Combination High Limit on the Burnham LE. The new ones are electronic with 3 buttons to control high and low limit. The old one was a simple dial with no differential control.
So the lowest that I can set the high end on the electronic limit is 180. The low is set to off.
Burnham has an optional EC5000 microprocessor with both indoor and outdoor control. Unfortunately it costs WAY more than Tecmar and Beckett/Intellicon.

Even more outrageously priced are the Viessmann brains.

 

I think that the Burnham EC5000 is a rebadged tekmar House Control 370. Or close to it.

 

You are right the EC5000 is a Tekmar control. The L8148A control has a built in differential I believe of 20º. The new electronic control also has the same built in differential.

 

Interesting changes to the PPT presentation (it is new today). Although I must say that the picture with the kitten staying warm is priceless.

Al.

 

Someone stated that we took coldest zone. I made it average rather than chilly. Most of our systems have many zones. In the case of single zone, not an issue.

 

The Kitten was easy. The train wreck took some doing.

 

Thanks Exqheat and rbeck about the control info.

 

New here, I am a professional and have been in the industry long enough to know. (yeah, I know there will be the "yeah right" coming)..

I just have to stand up and yell that I disagree with "indoor reset is the only way to save big fuel".

First off, long run times promote fuel economy. PERIOD.
They also promote comfort and (in the case of hydronics) more even heat ( to the extent possible by the balance of radiation).

Outdoor reset combined with a mod-con boiler is about the best it needs to be. If I wanted a pile of set back I would be concerned with linear indoor feedback (as opposed to the on-off indoor feedback we all have already). This will help the building recover from a deep night setback.

I have installed more Tekmar than I can remember, much of it Tn4 systems with complete indoor feedback, load sharing / shedding. It works great and all, but I can't say that its worth the money that it can cost. Simple outdoor reset (built into most mod cons) is really all thats needed. Provided you actually set it up correctly.

Not trying to start anything, but I really think people get over sold on controls. Modern thermostats have pretty good PID logic in them to keep a room where its set, with out anything anymore fancy than what ships with your new mod con.

 

Some folks have a problem with something new. Some have a problem with something old. What they cannot comprehend is something new for something old.

Step into an older building with an oversized boiler that is heating more than it should, and it is fairly clear that the landlord is not going to change out the boiler. When he does the "professional" is going to oversize the replacement.

The application of a modcon boiler on replacement will have a problem on a cold day. That asside, the choice now is to how do you tune a boiler to the heat loss of the day.

You can shoot 180 degree water around which will overheat the first 1/3 of the loop and over heat that part of the building, just make heat for the second 1/3, and fail on the last 1/3.

So you put in a reset control to tame down the boiler and increase circulation.

Do you use an indoor or outdoor reset. It would appear the professional would use an outdoot reset. The big question is how do you ADJUST the outdoor reset? Now that we have determined that the professional thing to do is heat the outdoor from indoors, that becomes a real problem. First the delay between the change in outdoor temperature and the heat loos effect is several hours. That is unless you live in Florida where the buildings are made of paper mache. The next problem is how do you adjust the outdoor reset for the other heat loss factors of wind, sun, building envelope, occupancy, and even comfort?

One needs to add the priority for comfort over efficiency. First you make em comfortable then you do that as efficiently as possible. This will require the use of some type of device. The best is a thermostat. Well then if you need to use the thermostat for comfort, why not use it for adjusting the source output, be it steam, hot water, heat pump or air conditioning for that matter.

As for long runs of the boiler. It is a known fact that the lower the High limit the longer the circulator will run. The greater the difference of the boiler fire and the circulating water the better the heat transfer factor. The water will rip the BTU's of the boiler as it is running more efficiently than if it is sitting there ready to boil. The difference between circulating boiler water temperature supply and return will be reduced to 20F, conserving boiler ware. Increased circulation at 60-70% of the time will supply efficient heat to the maximum radiation, at the proper temperature for even heat loss.

In an apartment building that is a great need, and it is well recieved, with existing equipment. The dial on an outdoor is most difficult to adjust. PID Is most overreactive if you look at the curve. As long as the boiler is running for 5 minutes or more the long run theory only applies on a design degree day, otherwise you cannot heat the building. Try that with your modcon. The chimeny will melt.

Go a go. Later.

 

I have been polling the local heating guys and it seems that outdoor, ie Tecmar 260 is the biggest seller here. Also selling is Honeywell AQ2514B4.
The indoor are also sold here but not at the same volume ie both Beckett Manager and Intellicon-HW+.

I called Burnham tech support to help choose one for a Burnham MPO with 6 zones. He said that on his similar system he has the Beckett which saved him 17%.

He said that there is no clear winner because every system and building is different plus the options to control.

I am vague on the options: the 260: "...designed to regulate the supply water temperature from a single boiler based on either outdoor air temperature or a DHW demand. The 260 can control either a DHW pump or valve and provide DHW Priority. A tekmar indoor sensor can be connected to the 260 in order to provide indoor temperature feedback from the heating system.

Does that mean you can use BOTH outdoor and indoor sensors?

"...either outdoor air temperature or a DHW demand..." but not both?

 

The argument for indoor is basically that the outdoor reset changes the temperature of the boiler hours before it is needed. So the boiler will be over temp, which makes the thermostat satisfy early, leaving a lower circulation rate, making comfort less well distributed, and standby loss higher. Indoor is a real time analysis of the thermostat over time allowing a precise adjustment of the boiler according to heat loss from the building. All the data shows up in thermostat activity.

For efficiency comfort at efficient boiler operation is the goal. This is what is needed in anything bigger than one family.

Go to the websites and study more closely. Remember, your buddies are at least five to ten years behind the times. Perhaps you should be the first to "try new things".

 

I think part of the issue with reset devices is understanding the boiler temperature requirement. This is not as critical as some make it out to be. How much of a difference is it going to make if the boiler it at 140 vs 145 F? Or, 90 vs 100 F (mod-con).

For years & years boilers have been banging off the high limit. With hardly a complaint that it is too hot, or suddenly too cold.

At that point I think we are splitting hairs. With either control (IDR or ODR) there is going to be a savings.

Then the outside temperature. It is not going to change 20 degrees within 5 minutes. It takes several hours for the outdoor temperature to cool off once the sun goes down.

I can show data on this if need be.

Which brings us back to the original question: how well does it work? Where is the data?

I know how well the ODR and constant circ works on the system here. I can see the calls for heat, boiler run time, water temperature at the boiler and returns, stack temperature and so on. By this Winter will also have a room temperature sensor at each of the two thermostats.

Al.

 

Tekmar 260 will give you a reset boil temperature, and a DHW setpoint temperature. It will give domestic priority (if you want).
It can use the indoor sensor to monitor room temperature and adjust the curve as needed (temporarily, it will not re-write the curve).
It has curve setbacks, etc.

If you want to go all out get into the Tekmar TN4 controls, they will learn your house and track 10 years of data. Not that the weather is the same all the time, but the trends are there. It does a whole lot more too (maybe too much for some)

 

Thanks so much for the input!!!

 

Always a stopper. I have good news. The first real study is in the works at the highest levels. I cannot tell you the details. The study will cover all the controls in a major reasearch quality study. I look forward to that. I have been campaigning for it for ten years, where ever I could find an open ear.

The data is garbled. Many claims are made from manufacturer to manufacturer. The insudtry does not like to advertise more than 15% savings, as there will be exceptions. A controlled study has to be done professionally, and that professional effort has not been encourtaged due to the fact that conservation devices could well save so much that the gas and oil lobby does not want government to go near it. Fortunately we have a President that is not limited to the influence of these folks as he raised his money on the internet in small amounts and has $ half a billion left over.

To the facts: Every building has a different envelope and a different heating/cooling system. The heat loss regain is a precise process of actual demand against actual supply. Exquisite heat has hard evidence on some projects that range from 5%-30% savings bill against bill degree day corrected.

Now some of that has to do with poor maintenance, (we get those items corrected). Most are conservation that was corrected by automating the control process to .05 degree boiler replacement temperature. On several projects you can throw in the savings of not having to change boiler sections which went bad every year due to high delta T temperatures. How do you fiqure that in? Where does better temperature distribution in a greenhouse as it affects plant hardiness, come in. How about fewer boiler failures due to not blowing the boiler off its foundation every time it gets chilly. How about returning rooms in the home to comfortable use in the winter time. The comfot intangible is awsome. What more how many total rip out of basements are avoided, by simply controlling what is already there. No mixing valves, No more pumps, no more thermostats. No more mumbo jumbo that cost a fortune.

Soon the data will be out ( 2 years). The wheat will be seperated from the chaff. What your buddy does will not be the guiding light anymore. Hopefully knowledge will determine the best alternatives. Meanwhile I use this little sucker in hot water, steam, hot air, and what ever else comes up.

 

Not exactly. The indoor sensor provides real-time, all-the-time feedback to the control. It actually seems to dominate the supply temperature specification, largely excluding the programmed heating curve and the outdoor temperature. It is a load-matching device and will dial down the supply temperature to the lowest possible to maintain setpoint.

It also provides a means for quick recovery from setback (because it tracks the space temperature) that standard ODR cannot do.

 

Let's please keep in mind that the exqheat is not a unique solution to the control of space heating systems using feedback from the heated space to the heat source. It is one solution among many that vary widely in technical application, suitability, cost, etc. etc. that can achieve the same end.

 

And to think this all started 40 - 50 years ago when the Hydronics Institute through the university if Illinois the constant run circulator and thermostat operating just the burner and found 25 - 30% savings working with cooler water in the system and (what they thought) squeezing all the heat input they can out of the water. With the pump running all the time the thermostat started the burner(s) and made the water warm enough to satisfy the thermostat and than **** down and leave the pump running. Old idea so simple make the water hot enough to meet the heat loss and keep people warm and comfort was much greater than the alternative at that time. They were way outside of there box at that time and people said why. They were stupid to waste all that time testing. Who would consider such a thing constant pump and move only the temperature water needed to satisfy the thermostat. Ha! Bah!
Hmmmmm!!!!!
Today we move cool water sometimes with a constant run pump. We use an expensive control to make this happen. Hmmmm!! 25 years of testing and a simple thermostat and constant circulation. 20 - 30% savings. Hmmmm! Nope we need expensive controls that dance through hoops to save 20 - 30% Hmmmm!
Do we? Is simple good? or do we have to spend hundreds of dollars for controls to get the 20 - 30%? Hmmmm!!!
Ok they did say the most savings was with large water volume systems. The less water volume the less the savings. Since we do not see any large water volume systems anymore, not any cast iron radiator hot water system around in 2009. Nope! Hmmmmm!!
Could this be an alternative to expensive controls for the customers that just can't afford the new more accurate, better control and great features? Even if they can't afford the best control they sill are entitled to save what they can. There is an option.
And I haven't even mentioned two stage thermostats yet!!!!!!!

 

Couldn't have said it better Ron. The refinements with newer controls, are that we better know what high limit to take it to without going all the way up to 190 on a less than design degree day. This insures better comfort and a savings of an additional 1% for every 2 degrees less in high limit. You may remember the delay in communication from the radiator to the thermostat. (anticipation). Real time hourly analysis removes the overshoot. Folks since then fiqured out the condensation problem and the creation of Sulfuric acid that resulted from low temps in the boilers??

So to fine tune the process to deliver optimum mean temperatures of supply water without excessive short cycling, above condensation temps, the modern controls were developed to maximize comfort first, then to deliver that comfort as efficiently as possible, with longer equipment life through reduced condensation of exhaust gases and reduced difference in exit and return temperatures for reduced thermal shock damage to the boilers.

By taming the boilers the effective efficiency is raised in terms of fuel used for the comfort delivered, with extended boiler life.

 

Kinda what I said but with better words !
I know it does all that, but it did not seem to be a required part of the answer. I did not want to add any confusion to my post.

Sorry.