Paging Mike @ Tekmar

Neil_5

Hey Mike:

Thanks for the support last night regarding my 256 and the circulator being off when the boiler tunrs off, yet zone valve is open.

Man the house is heating great, all the cold rooms are now comfy, wife is happy, hence I am happy!!! Actually, now had to lower my water temp (ROOM of 73 to 70) which is a good thing, however I have the same problem as a previous poster with the Auto Diff setting, boiler turns on for 10 min and off for only 3 mins :( Had to go the manual diff route. Any other suggestions? Like the previous poster, the 256 anticipates the drop and "train valve/damper" turn on time and fires a bit early.

My next "thing" if you may:
I had an extra whiet roger relay which I used to power the circulator etc as we agreed on per fig A256-2. However the current relay (mounted on the 24 VAC of the boiler) is not really used at this time, so in essence, I can used that relay, with the relay being powered the same wasy as A256-2 and the 2 outputs of the relay can control the circulator and the damper/valve. Which is redundant for the damper/valve, coz these guys are controlled by the relay out of the 256. The entire system is protected by the LWCO. Do you see where I am comming from regarding MY application so far? This way I use one relay which is already mounted on the boiler for a cleaner look.

What are your thoughts?

Neil (Long Island, NY)

hydronicsmike

as long as...

...that Relay in the boiler is energized by the Zone Valve Motor End Switches and the Circulator runs when ever there is a call for heat in the building and not only when the boiler fires, no problem.

A 10 minute on-time is good. Keep in mind that the Auto Differential tries to give you sifficient cycles while the temperature swing is kept at a minimum. Its pretty much giving you the best it can. The higher the differential and temperature swing, the higher the losses. The Control tries to keep the temperature as low as possible to minimize those losses. It is always best to keep the Diff at Auto.

Am glad the wife is happy now though, which in turn keeps you happy. Same ol' story...

Call me, should you like to discuss further. If I dont hear from you, have a great weekend.

Regards,


Mike

Neil_5

Plans

Mike:

My Plan is to use the zone valve end switch to power the "boiler relay" and one of the relay contacts for the circulator (so that takes care of the end sw controling the circ) and another output of that same relay for the damper/gas valve WITH the 256 boiler output as part of that series chain, so 256 boiler out controls the firing of the boiler.

In the auto diff mode, the ontime is ok at 7 mins, but the off time is like 2-3 min, is that good for the boiler, to re-fire in 2-3 mins? PLUS the fact that the 256 keeps the temp of the boiler close to the target, after 2 cycles, the ontime now becomes like 4 mins and off like 3 mins .... is this good?

Will also try lowering my curve (ROOM setting).

Thanks,
Neil

hydronicsmike

I would say yes

it is satisfactory to have those cycles.

Does the cycling come and go with the demand? Or does it happen while a demand stays present?

Mike

Neil_5

Demand

While the demand stays present (stat calling for heat correct?) the boiler cycles as I mentioned above. Could you "splain" a bit more for me.

Neil

hydronicsmike

Demand

Yes, the demand means a call for heat fom a thermostat. But what I meant by that was not only a thermostat was calling, the Control should have had a pointer on the Boiler Demand labelling (bottom right hand corner of screen). If you see this demand pointer cycling when the boiler cycles, there is nothing the control can do to override that. If the boiler cycles when the Demand pointer is visable permanently during this operation, then the Control cycles the Boiler to its best capabilities.

Hope this is more clear.

Regards,

Mike

Mike

Neil_5

More on Demand

Mike:

The demand pointer is there fixed (does not cycle) while this is on, the boiler cycle seems a bit to much at 4 mins ON and 3 mins OFF (in Auto diff mode) Maybe lower the water temp a bit?

Neil

hydronicsmike

you can....

...give that a try. Lower your ROOM Setting by a couple of degrees, which will result in a lower water temperature target (unless already at BOIL MIN). The Control will most likely recalculate the Differential it uses.

Who says 4 minutes is not a good cycle? Where is this coming from?

You can always go to a manual differential if you're not satisfied with what you get in AUTO mode. But why increase your losses for no good reason? Where are you getting the idea that a 4 minute cycle is bad for a boiler. The goal is to keep temp as low as possible to minimize losses. Longer on times mean more temperature swing - higher supply temp - higher losses.


Mike

Neil_5

Cycle Times

For some reason I have this notion that having the boiler cycle 6-8 per hr is not good.

Longer on times mean more temperature swing - higher supply temp - higher losses >>>>>>>>>>>> I get this now

Neil

hydronicsmike

I agree that.....

...it would be the absolute best system if we could have the boiler on all the time and the temperature within 2 degrees at the TRG during BOIL MIN. However, this is not possible if the load isn't there.

When ever the Boiler is oversized, the cycles are shorter. We have no control over the physics of a system. We can try make the best (as we feel) of what we have. Even if a boiler is sized 100% to the Outdoor Design Load, it is still oversized for most of the year. The Control uses PI logic and is designed to give you best performance while trying to minimize short cycling as best as it can and to minimize temperature swings as best as it can to minimize losses and therefore increase savings as best as it can.

The Controls are designed to maximize (system) efficiency and fuel savings. If you want to maintain specific run-times, use time delay relays on the boiler. But don't expect savings to come out of it.

Regards,

Mike

Neil_5

Getting the hang of this all ...... Thanks for all your input Mike.

Neil

hydronicsmike

You are always most welcome...

...Neil. Thanks for giving me the opportunity to give input.

Have an excellent weekend.

Mike

Neil_5

Mike

> Hey Mike:

>

> Thanks for the support last night

> regarding my 256 and the circulator being off

> when the boiler tunrs off, yet zone valve is

> open.

>

> Man the house is heating great, all

> the cold rooms are now comfy, wife is happy,

> hence I am happy!!! Actually, now had to lower my

> water temp (ROOM of 73 to 70) which is a good

> thing, however I have the same problem as a

> previous poster with the Auto Diff setting,

> boiler turns on for 10 min and off for only 3

> mins Had to go the manual diff route. Any

> other suggestions? Like the previous poster, the

> 256 anticipates the drop and "train valve/damper"

> turn on time and fires a bit early.

>

> My next

> "thing" if you may: I had an extra whiet roger

> relay which I used to power the circulator etc as

> we agreed on per fig A256-2. However the current

> relay (mounted on the 24 VAC of the boiler) is

> not really used at this time, so in essence, I

> can used that relay, with the relay being powered

> the same wasy as A256-2 and the 2 outputs of the

> relay can control the circulator and the

> damper/valve. Which is redundant for the

> damper/valve, coz these guys are controlled by

> the relay out of the 256. The entire system is

> protected by the LWCO. Do you see where I am

> comming from regarding MY application so far?

> This way I use one relay which is already mounted

> on the boiler for a cleaner look.

>

> What are

> your thoughts?

>

> Neil (Long Island, NY)

Neil_5

Mike: Some Cycle Numbers

Over the weekend I noted some on/off times with manual diff VS auto diff, 7 ON/OFF times were recorded for each setting. (data taken after house is stabilized; not comming out of setback, demand is constant):

Outside Temp: 35-36*F

Diff Setting: Manual (40)

Boiler Min 140, Boiler Max 190, ROOM 68.

Target Temp: 143*

Delta (OFF temp to ON temp): 30 deg

ON Time: 3 mins OFF Time: 9 mins

Cycles/hr: 5 Boiler ON time/hr: 15 mins
===================================================
Outside Temp: 35-36*F

Diff Setting: AD

Boiler Min 140, Boiler Max 190, ROOM 68.

Target Temp: 143*

Delta (OFF temp to ON temp): 20 deg

ON Time: 2 mins OFF Time: 7 mins

Cycles/hr: 6.7 Boiler ON time/hr: 13.4 mins

As you said on Friday, AD seems to be much better, for one the temp swing is 10* less, the ON time is less Will take some more data when the temp is lower, say in the 20s to compare cycle times (doubt at this time of year we may get back to the 20s in NY

Just wanted to share some #s with you, looks like I will be in the auto diff mode

Neil

hydronicsmike

In either case....

...the numbers provided seem good to me. You'll have to look at an overall cycle and based on the numbers I see, your on-time is within 25-30% per cycle.

The manual differential setting is an anticipated differential, but will be overidden by the Controls PI logic. The Control will give you the differential you ask for, if it has to and can do so without compromising system efficiency. Otherwise it will reduce it to a differential that Control sees fit.

Under full load conditions you would and should get your manual differential, unless the boiler is oversized.

Please call, should you like to discuss further.

Mike

Neil_5

Funny Thing:

I can actually heat the house when temp is above 28*F with 140 deg water , before it took 185 deg water to do so. My last 3 mths gas usage was approx 330 therms or $409/mth

Now this should all change PLUS I added R25 to the R30 in the attic and am in process of insulating the basment plus replacing the 1955 wood windows with modern efficient windows. So 2005/2006 winter should be good to my pocket. Can't belive the mistake or lack of knoweledge of the tech who wired the Tekmar 256. I would say lack of knoweldge, coz he wasnt sure of the parameters to enter Thanks god I was able to pick up from there and program the controller properly AND find the circulator was wired incorrectly, cost me a few hundred in gas bills I must say, but lesson learn. At one point I was questioning the 256

Neil

soot_seeker_3

who wired it?

'Can't belive the mistake or lack of knoweledge of the tech who wired the Tekmar 256.'

neil, just curious who wired it? big company or small company?

you bought the control & they charged for install or they provided control & install?

ss

Neil_5

Decent Size I may say, not a small company

I am in Long Island NY .... I told him I want the control install with the new installation, he order it and installed it.

Neil

soot_seeker_3

yup same

'Long Island NY '

yup, huntington town here.

did it myself 'cause nobody knew what it was.... as per usual.

used to think LI was ahead of the curve - at one time -grumman - lunar module - all that. now we're turning into the 'sticks'. (also doesn't help to have a big town called hicksville - does it).

ss

Neil_5

hahah

I did the ref/back ground on the company (he wasnt the lowest bid etc) and the owner is very knoweldgeable, but always in a hurry it seems. The guys did a great job bringing the gas in and the copper piping is beautiful, have no complains there. What I would like to have seen (and this is after the installation I learned all new things here on the wall)

Heat lost should have been done and match the boiler instead of swap out and in. Luckily for me, I did a heat loss and found the boiler is not that oversize.

The techs had no clue about mono flow systems, now that my system is working properly, its a beautiful system

They called in their top guy at the end of the installation (very nice guy)to perform the wiring and install the 256 (had I knew it was so simply). I am a new home owner last July, so I had a lot on my plate with other projects and being an EE the wiring is very simply to me. Well I always look on the bright side and the bright side is this only went on for 4mths and not 4 yrs eh?

I am in North Bellmore, broder with Eastmeadow.

Neil

hydronicsmike

Howdy guys...

Luckily enough, on Long Island and the City you have one of the best Reps we have in Don Rathe at Rathe Associates in Syosset at 516-433-8100.

he can always help you out. He can also make recommendations on Contractors and Electricians to stand by your side, when ever tekmar Tech Support is not available.

One thing I am sure you were aware of, but wanted to make sure you'll know in case you didn't: Outdoor Reset saves you money in the Spring and Fall mostly. Basically, when ever you are not at your Outdoor Design conditions. If you are hit by another record winter with very long and cold winter days, the savings are going to be smaller.

Thanks for the feedback guys. We always appreciate it! If there is anything you need help or clarification with, you know how and where to get me.

Regards,

Mike


Mike

soot_seeker_2

yup same again... EE

'being an EE the wiring is very simpl'

yup same again... EE for 25+ years & computers for the last 20+ of them as well. having fun with heating stuff now.

our latest saying on one of the other boards:

for oil:

'there is no such thing as an oversized boiler - just oversized nozzles'.

for gas, i have no idea.

ss

soot_seeker_2

tommorow night - in the teens ...

'doubt at this time of year we may get back to the 20s in NY'

looks like tommorow (tuesday) night you'll get a chance to test again - temps in the high teens.

those are the good nights to test & adjust since you'll have the heavier load & longer cycle times. if i downfire any further, my boiler nozzle will be smaller than my hot water nozzle.

ss

Neil_5

You're Right

SS:

got some low #s to run some experiment

Outside 21, target 168
Now I have 5 min off time instead of a 7 and on time remained at 3 mins. Auto diff. House target at 73*

What are your parameteres SS, just curious since we are in the same region ... type of house etc?

Mike/SS: I spoke with Glenn S. of Burnham and his recommendation for return water temp is >138, which depending on your system delta would put your supply at 150-160 min. When temp is above 28 I can heat the house to 73 with 140* water. What are your views on this?

Neil

hydronicsmike

I will most certainly not go against...

...what Glenn Stanton is telling you. He is a very knowlegable man and a mentor to many people, including myself. Always go with what the Boiler manufacturer tells you. In the end, the Boiler is one of the most expensive parts of a system and it's protection is very important as any savings (by reset)would be right out the window if the boiler failed.

However, I know a lot of systems with cast iron boilers that operate at 140°F Supply and 120/125°F Return. Condensation would not be a problem there, I dont think, because any condensation that would occur below 130°F, would burn off while the boiler temperature is increased and brought above 140°F while maintaining BOIL MIN and AUTO DIFF.

The 140°F Return, again I would only suspect, is more for Thermal Shock Protection (deltaT to high between boiler Temp and cold returning water from the system).

Mike

soot_seeker_2

stuff...

'any condensation that would occur below 130°F, would burn off while the boiler temperature is increased '

i'm hoping this is true but i'd also be curious to hear it from mr stanton as well - (maybe he'll see this or we can post it over at oiltechtalk). i believe he has stated something to the effect that their warranty assumes a 'sustained' minimum operating temperature of 140F. not sure precisely what that means during the full course of a boiler's normal operation. but i'm getting the feeling that such a statement requires primary / secondary piping which you may or may not have. as far as cold start or warm start below the minimum, you'll have to ask him for the detailed definition.

neil: a 168f target at 21f outside sounds like your design day is set closer to 0f than mine. i think i left mine at 10 or 11f because of an under-heated zone i have consisting of single fin-tube that seems to need the extra temp to warm it up. i'm hoping to change that this summer & double up on that zone so that i can run a bit cooler for next season. i'm not sure exactly what type of boiler you have but in my case it's a 25 yr old ci and (as mike knows) i've been experimenting with the manual diff settings to get longer on cycles as well as downfiring the burner as close as i can to achieve a continuous on cycle when experiencing a 'typical' design day load. and by that, i don't mean an actual design day for our area (maybe -3F) but rather the typical worst case *repeated* temperature that we would normally encounter during the last 2 weeks of january (our normally coldest period). we rarely get more than about 7~8 days below 10f here in jan (and some years none at all) so rather than try to get the system to run continuously at say 5F, i think it makes more sense to try to achieve somewhat continuous operation at about 15f (this obviously varies depending on your house - i'm dealing w/ 2600sq ft & 1964 construction & insulation- which is to say not much). the point of this tuning (in the absence of having a modulating boiler) is to get longer cycles at temperatures above 15F as well as maximize efficiency by eliminating or at least minimizing the *on/offs* which are detrimental to the efficiency, longevity of the equipment, & system cleanliness.

early this morning when the upstairs & (most of the) downstairs t-stats came out of 'sleep temp' mode, it was about 13F outside. the boiler ran a couple on cycles of ~20min & ~10min off. that's about a 2/3 duty cycle which according to 'the plan' means that i'm still oversized even with a .75gph nozzle. but i had to wait til last night to see this since we haven't a 13f night in a while. i just ordered some .50 nozzles in order to come in from below & pressure back up if i have to.

this article explains all this:
http://www.pmmag.com/CDA/ArticleInformation/features/BNP__Features__Item/0,2379,122286,00.html

when i had the T256 set to auto diff, it tended toward a 50% duty cycle which might be good for the average boiler (especially since the T256 doesn't know what kind of boiler you have i.e. lo-mass or hi-mass) but in my case i had some short cycling and thus i'm trying to use the manual diff to get me closer to continuous until i get the smaller nozzle in there. like i said for gas, i have no idea how this is done other than using a modulating boiler.

ss

Neil_5

My Stuff

SS:

Thanks for the info on your system: Now for mine. I have a split level ranch with 90% convectors (man no BB cant beat them) and 10% BB which I am replacing after the winter with Hi-output BB which will give me approx 50-60% more heat output. House was design on convectors in 1955, as they update, they replaced 3 convectors with BB. Bought the house last July. Monoflow system, and gas , converted from oil to gas when I moved in and have a new Burnham Series 2 boiler 130k BTU.

256 settings: Design is at 10*. min is at 145, boiler design is at 185*. ROOM is at 68, this pretty much keeps anything from 29* and greater outside at my 145* min.

At the low 17* outside, I am now running 3 mins on and 5 mins off. what duty cycle is that: 38% or 62% duty cycle?

Do you have any sec/pri piping? I dont, I have low mass return water, and I think this is ok for me so far.

You are correct when you say our design day should be around 10*, at times can go lower but that is very rare.

Insulation: I now have R44 in the attic, the walls have suffiecint I think, didnt feel cold when we went down to 17*, so I assume they upgraded from 1955 I have new windows and doors and I hit every corner to reduced drafts including outlets. Garage ceiling which the MST bedroom is over will get R25 in the summer. I am in the process of replacing the 1955 wood windows in the basment and insulating the walls with R13. So the first floor should be warmer next winter if I keep the basement at say 72*

Neil

Neil_5

SS:

I see you're looking for hi-output BB, go to this web site:

http://www.2haydon.com/baseboard.html

look at the hi-output 958, which puts out 850 btu/hr per ft compare to 550 for regular BB. And I like the idea of stacking them as one poster pointed out in the Wall with the hand drawing.

Supply house:

Victoria Plumbing in Mineola: 516-741-4343 ,ask for Mike very helpful
Patriot Supply in Plainview: 516-249-3100

Both of them carry the Haydon BB.

Neil

Unknown

Neil

In response to your latest e-mail, I advised to try and keep the return water temperature above 140°F. I also explained that most controls such as the Tekmar 256 and others are sensing the system supply water. If you set that for 140°F you will not necessarily be getting 140°F return water. This return temperature will be dependant upon zoning, temperature differentials across the system and other variables. Prolonged operation of an atmospherically vented gas boiler at return temperatures below 140°F may contribute to flue gas condensation in the boiler flue passageways, vent pipe and chimney. The key words here are "prolonged operation" at or below 140°F.

The dew point of Natural Gas is at or about 138°F and with the 50% excess air we introduce into the combustion and venting process this number actually is at or about 127°F. That is if all of the variables of available combustion air and venting are in the acceptable range based on the installation. The issue is not thermal shock but rather the possibility of condensation within the heat exchanger or venting. Yes, if the condensation does possibly occur for a short duration it will indeed burn off, but we would desire not to see that happening for a "prolonged" period of time. If this were a boiler such as our Revolution or Revolution II boiler that monitors internal boiler water temperature and varies the flow through the boiler with a variable speed pump and control, then it would not be an issue. Hope this helps.

Glenn Stanton

Manager of Training

Burnham Hydronics

www.burnham.com

Neil_5

Glenn

Thanks for bringng our off line email to this post, as Soot seeker is in the same boat as myself and both of us are trying to balance our system. Always appreciate your input.

Personally I think all boilers should operate like the Revolution or Revolution II boilers. Had I known this info I would have upgraded.

I will measure my return temp and see where my delta is and program the 256 accordingly to balance efficiency and protection of the boiler.

Boy of boy this is whole world by itself, had I left my system up to the company that installed it I wouuld be paying $500/mth in gas and have a 50% efficiency heating system and a rusted out boiler in 5-10 yrs maybe.

Glenn, what volume of air is needed for combustion, I am in the process of insulating my basement and replacing windows etc, do I need to make any provision for air intake to the boiler?

Glenn and Mike, thanks for helping out a couple of ole homeowners here.

Neil

eleft_4

SS, oil burned????

SS,

How many gallons burned since the first of the year?

al

soot_seeker_2

need to check..

i haven't had a chance to stick the tank in the last 1.5 weeks & most of the downfiring that i'm doing now i only started mid february so i'm probably not going to see an immediate improvement but my rough guess would be about 400 gallons right now for the boiler & separate oil fired hot water heater. that may not be impressive for many but on the average that's pretty good for me at the moment compared to last year. i probably won't get to see any real detailed comparision data until after this season & maybe next year by march for which i can then compare to the previous years. i've changed a lot of things over the past 4 months & am still tweaking the system so i expect the trends to be positive but slightly erratic. i have a new hi-speed burner coming in to replace the old 1725rpm on the water heater this week - so i expect i few more things to change. when i get some time, i'll try to do an equivalent degree day analysys & see what i'm getting.

ss

ss

eleft_4

BTU in BTU out!

Why I ask, it won't matter how efficient you think you are making your system, if you are heating the atmosphere the oil consumption won't change much.

al

soot_seeker_3

two things......

"'it won't matter how efficient you think you are making your system, if you are heating the atmosphere the oil consumption won't change much.'"


there are always two things to consider:

1. the integrity of the envelope.
2. the efficiency of the source.

#1 basically means the structure has to be insulated to hold the heat (for the moment, i've attacked the worst offending spaces & cracks by walking thru the house with an infrared laser thermometer & buttoning up the worst leaky / offending areas (and i found some good ones). the attic will be next.

#2 basically means you need to produce that heat in the most economical fashion - even if half of it is leaking out the roof. if i increase the efficiency of my system & cut the costs to produce that same heat, then i saved money anyway for moment - at least until i get the envelope in better shape.

both of these components eventually have to be satisfied toward the ultimate goal. any time invested in either one, in any order, will move it along toward completion.

ya gotta have a strategy in life - if only for the moment.....

ss

" it's not that people plan to fail, but only that they fail to plan..."

eleft_4

\" it's not that people plan to fail, but only that they fail to

plan"

Which of these are you working on?

If you are heating load is greater than your source what gives you the clue you can make it more efficient by de-rating it? How much fuel burned from the first of the year, check your del ticket, it has gallons on it.

al

soot_seeker

more stuff..

if the load were greater than my output source then i wouldn't be worrying about my on-cycles since the boiler would never shut off while trying to keep up with it.
then the house temp should eventually fall short of the t-stat target - haven't seen that yet. the gallonage info for this season i mentioned about 4 posts above. so far, it seems like i'm on the average using 2.5+ gallons less per day over last year to heat the same. but i still need to compare degree days once all the bills are laid out. degree days seem pretty close right now.

ss

eleft_4

??

How much FUEL BURNED from the FIRST OF THE YEAR (JAN 1,2005)?... check your del ticket, it has gallons on it.