LuckyD... Most of your recent posts have been about short cycling issues.

Can we go back to day one? Was that boiler matched to the heat loss of your home? I assume your installer or someone did a proper heat loss calculation?

That is a five-section 140,000 gross Solaia boiler. An oversized boiler will short cycle, and there aren't too many quick fixes for the problem. I'm not saying that's the problem, but my three section Biasi boiler is two sizes smaller and is 2X too big from my 2,000 sq. ft. ranch in northern CT.

 

Eons ago, in one or more of half a dozen threads on this building/system, the heat loss and the radiative capacity were done. I have a dim recollection of suggesting a boiler in the 90k range. This was approximately the manual J heat loss (which IIRC was hugely overestimated), approximately the radiative capacity, and would have been fine for a 40 gal indirect. Maybe a tad under due to an unknown output of a convector-style rad that was estimated at 20k output. There was also some silly-high estimate of piping losses, but I don't remember if it was done by the person who ultimately installed this boiler.

So yeah, this is a jet engine on a canary. Or maybe a blue jay.

I still don't quite get the piping strategy here. Is it really a full primary/secondary? If so, is the supply sensor on the primary or the secondary? It kinda looks like it's on the primary. Should be on the secondary.

 

And why P/S???? The Solaia boiler has an internal bypass, much like your Burnham.

Nothing explains the burner shutdown before the 15-sec. Riello prepurge cycle is finished, however.

 

Unsure what burnham you were talking about. And I have no idea why the P/S. I thought that was to prevent cold water from cracking the boiler but i'm no expert. if the boiler already has that, then are you saying he unnecessarily duplicated all that external piping? I cant believe he would do that.

I dont see anything about internal bypass on these pages.

Products - Solaia Boilers -Boyertown Furnace Company



http://www.boyertownfurnace.com/imag...ia%20Flyer.pdf

i have the 122 DOE and the next lowest is 91K. My house is almost 3000 sq ft according to a recent appraisal, but who knows how accurate that is.

My own heat loss is below but i do recall i made a few minor errors and went back and corrected it..i think it was less than 5K but forget which way. Also the installer did take over 1 hour to measure all the rooms etc and he said he came up with about what i did. I guess he didnt want to chance the 91k unit in this big house. I have to say that my bedroom was 70 overnight despite the 67 on the stat. So i may kick it down to 66 overnight. I think i overinsulated that room by foaming up under the window lol

 

My drawing shows the basic piping setup, as near as I can determine from the pictures. The primary loop is the system, or heating, loop. The secondary is the boiler loop.

Lucky, did you say in one of your posts a while back that the installer dude said you have ONE HUNDRED gallons of water in your system? Really?

Not sure why you can't grok the flow Lucky... there's a pump on the boiler loop... the pump is creating a pressure difference. If there's a pressure difference, there MUST be flow. If it's pumping water OUT, then it must also be sucking water IN ... there's no getting around that. Higher pressure on the discharge of the pump means there is lower pressure on the suction side... how can water be pumped out if no water is pulled IN ? Just not physically possible. Where the water that's pumped out goes after it's pumped out is sorta irrelevant, because the fact remains that water HAS to go back IN to replace what comes out.

Yes, it's a tangent, but you should try to understand it...

Remember, what goes IN to a TEE, MUST come OUT of a tee.



In this example, the flow through the boiler is greater than the flow in the system. I'm not saying that this or the other pic is the way your system actually flows... these are EXAMPLES to show how it would flow given different conditions.

 

OK. I'll stand corrected on the internal bypass, I thought that was added in the Solaia, which is really a Biasi boiler casting by the way.

I can't comment on your heatloss figures, but this thread(s) goes soooo far back that the previous postings. A major cause of short cycling is an oversized boiler, so that's why I brought it up.

Jeff, can you draw a schematic of the piping?

 

yes 2 of the 'big companies' here measured the 191 ft of pipe but the guy that i actually choose did come in and measure the entire house. So thats why i went with him (among other reasons) I certainly didnt want the 150K + boiler the 'salesguys' were recommending.

I dont know the piping strategy here either, which is why i still cant resolve troopers explanation to me sitting down and studying the pipe in real life. Now i just figured i'm not a plumbing type of guy but if after all these pics you guys are saying there may be something wrong, i'm open to telling this guy that if i can understand what i'm doing. But he thought this out and im sure did it the way he's always done it. I dont see him changing the piping just for me unless i have real solid evidence it's wrong

I wish there was a whiteboard type thing i could use overlaying my pics to try to figure how the flow goes. If the goal of his is to have a mix of water with the same temp thru all that piping above the boiler, i'm pretty confident he did that. Personally i see no 'direction' to the water at all.

But i feel something is amiss that the hot water in the boiler (or even in the baseboards) is being fed directly to where the sensor is and upon starting the circ, that hot water gets the pipe so hot it makes the sensor STOP the boiler just as it wants to ignite..no need to fire. 15 seconds of circ got me all the hot water i need to meet the call for heat.

smart 40 calls for 122K output..the DOE of my current boiler is 122K ...so do you think that was a determinate as well for the current boiler?

Performance

 

i told him about the 191 ft of baseboard and he worked out some formula in his head and said that's about 90 gallons then added for extra pipe i guess and said 100 gallons. I am looking thru comfort calcs site to see how much 1 1/4 pipe holds per foot..though im' sure there's another way to calculate it for you math majors. Personally i think he's off..i'm just thinking of how many copper pipes would fit in a one gallon jug of milk and it's a bunch.

I'm taking new pics and will somehow label them to ask you my questions..i studied the system again and i can see how the pump would draw hot water TO the supply of the baseboards but i cannot understand how any water ever gets back to the boiler. IE makes it UP that one T vs continuing back to the supply side.

will post back the pics in a bit

 

In this example, the two flows are equal. All the water that goes through the boiler is going through the system.



Pete, this is basically what's there, with the exception of the indirect connections. The indirect is in parallel with the load.

 

If the system pump is running, and the boiler pump is not, this shows the flows... again: not saying this is how much your system flows, the numbers are EXAMPLES only.

Remember, what goes INTO a tee must come OUTOF a tee.

(Pete, the electrical analogy is Kirchoff's law, swap flow for current)

 

OK, last condition ... boiler pump ON, system pump OFF.

 

If you dont mind could you get another pic like this one but maybe two steps back so I can see whats what.

 

This is the basic system, with the indirect shown, based on all the past pictures and what I can see in them.

NH, if you go back through Lucky's threads, you can see the whole system, there's plenty of pics already.



Lucky, by the way... black electrical tape is NOT "insulation" ... that sensor needs to be INSULATED!

 

Jeff :I'd think the boiler and heating circulators would be wired in parallel and run simultaneously? The indirect should be directly across the boiler supply and return to make sense. Why run two pumps for the DHW??

 

quick question...should the right side pump at 0, which i assume is like the pump right next to my ratting elbow/valve down supply line, be at 0 until the boiler gets to hi diff? or should that pump turn on as soon as the boiler kicks on so that some flow is to be had?

 

isnt not tape..at least like none ive ever seen...it's kinda like when you go get blood taken that bandage around your arm they put on after..it sticks to itself and is stretchable.

----------
btu_pipe

says .065 gal per lineal foot at 1 1/4 inch...so would that be 191ft pipe x .065?

= 12.4 gallons? maybe a few more for other piping

 

Black rubber electrical friction tape is NOT insulation.

That sensor, and a foot or two either side of it needs to be INSULATED.

 

Note: The boiler pump should not be operated by the boiler’s aquastat, as this may lead to
improper cycling of the boiler because of inconsistent flow past the boiler supply sensor.
BOILER DIFFERENTIAL (BOIL DIFF)
An on / off heat source such as a boiler must be operated with a differential
in order to prevent short cycling. When the boiler supply temperature
drops below the bottom rail of the differential, the 360 closes the Boiler
contact to fire the boiler. When the boiler supply temperature rises above
the top rail of the differntial, the 360 opens the Boiler contact to turn off
the boiler. With the 360, either a fixed or automatic differential setting is
selected. If automatic differential (Ad) is selected, the 360 automatically
adjusts the boiler differential under the current load conditions to avoid
short cycling.
BOILER SENSOR ON THE RETURN (Boiler Sensor DIP switch = Return)
The boiler sensor should be located on the boiler return if the 360 is one of many controls
that can call for boiler operation. When in the return mode, the 360 provides a boiler
enable as described in the BOILER ENABLE section. The 360 no longer tries to control
the boiler supply water temperature directly but allows the boiler to operate at its operating
aquastat setting when required. If this mode of operation is selected, the boiler pump
should either operate continuously, or be operated in parallel with the system pump contact
(Sys Pmp).
Note: The boiler pump should not be operated by the boiler’s aquastat, as this may lead
to improper cycling of the boiler because of inconsistent flow past the boiler return sensor

Hmmm, very interesting.

 

1. at T1 i understand the boiler is pumping water through it and goes to the right and out to my supply to the baseboards. But what prevents the water from turning left to T2?

2. The return coming from left to right passes through T5 then heads to T2. why does ANY water go up at T2 and back to the boiler return? I dont get why the water wont just continue on to T1 and mix with new hot water and go back to the supply. I guess the answer is because of pressure SOME water has to go up and over to the return?

3. based on my descriptor tags, can someone tell me what is the primary vs secondary? I keep hearing those descriptions on here.

4. When does the water ever go to the expansion tank..the T3 down pipe leads to the tank. I dont get how/why water gets there and under what conditions.

5. The T5 is on the return from the baseboards. What prevents water from T2/T1 heading back to T5? Is that copper thing to the left of T5 some kind of valve that prevents that and makes it one way flow? This is one of the things that boggles the mind..that HOT water from T1 doenst make it to T5 (or even reversing to the DHW outlet pipe there)

6. Asked before but to the left of T4 is the supply circulator. When does that turn on (instantly with the boiler circ or waits until target temp or high diff is reached).

7. can that supply circ and the DHW circ ever be on at the same time (that's the circ up and to the left of T4 i assume)

8.on the pipe that leads to the left of T3, what is that valve? i assume it makes sure the water doesnt head back to my cold water supply? but was wondering if it 'autofills' the boiler if need be?

9, now that this is a better pic, does anyone have any suggestions where else the sensor should go?

 

Tekmar 260, an ODR control. Tekmar 360 is a mixing controller. Different devices. The sensor for the 260 must be on the supply for the heating emitters...

 

are you talking about the typical foam pipe insulation like i've used on the outside oil line in the past?

or suggest something else to me. I did ask him about insulation before and he said that the pipes actually heat the room, it's not like i'm losing heat in a basement which shouldnt really be heated.

i have no problem getting some insulation on it all per your advice

 

NH, it's a 260 ... I don't believe there's a sensor location option dip switch on that one...

Pete, I agree that the indirect would be better served coming directly off the boiler loop ... but other than wasting the electric to run both pumps, it will work ...

That's all for my big mouth for now... play nice kids!

 

That sensor is in wrong spot should be on that riser pipe coming off the boiler.

Its getting mixed/return water. Hence the short cycling, Large temp spike, then cold return water.

 

I question it because there is no wiring scheme for controlling the pumps when piped like that. How do you control the boiler pump on a DHW and/or heating call? You'd need two slave relays just to control the boiler pump on either call.

 

It belongs on the system supply, not the boiler supply. Look at the manuals.

 

I'm going to try to pretend i know what you are talking about and decode what you said. Do you mean instead of how he has it with the pump, that the pipe from the boiler would run directly into the DHW tank and then the return from the DHW tank would be piped into the T1 in my example? In other words, the DHW would always be the first one to get any heat made no matter what?

If that's true then my guess he did it like that to avoid 'wasting' the heat on constantly sending the heat/hot water i may not need for an over 20+ hour period. Most days, except for a shower, there is NO DHW demand at all. I may do the occasional pan in the sink after dinner but all the dishes wait for the dishwasher. I use very little hot water. So keeping this in mind, does his arrangement make more sense?

to avoid me getting confused...does that mean i can ignore post 138?

 

while the sensor may not be in the right place now, i cant imagine if i moved in on that vertical pipe right out of the boiler. This would create even more short cycling and the thing may never even start up Moving the sensor towards hot water is something i'm pretty sure is something i shouldnt be doing.

how can i check gpm? is that something written on the pump?

i see RPM here not GPM

http://i371.photobucket.com/albums/o...s/IMG_2134.jpg

 

Again I was looking at a general 360 schematic, rats.

 

this may or may not be important but i noticed he has the tekmar terminal set to 5- radiator

i have baseboards (numbered 6) except for one radiator in the only upstairs room.

would this have anything to do with anything? maybe it thinks i have more water than i do? Just grasping at straws here

i know he kept referring to my RADIATORS when he was here but i thought it would be rude of me correct him that i had baseboards.

so think i should change it or no?

the manual states for
radiators design is 160, max is 180, min is 140...
baseboards design is 150, max 170, min 140

my other settings since the probably got lost in the clutter i made (seems like he has it set for radiator more than baseboards doesnt it?)

occ room 70
unocc 65
otdr design 0
terminal unit 5
boil indr 70
boil dsgn 167
max 172
min 125
diff 24 (MY setting yesterday to stop the short cycling, he had 16)
wwsd occ 70
wwsd unocc 60

 

LuckyD. What do you consider to be baseboards? True baseboards are cast iron, many folks call covered fin tube "BaseBoard." There is a difference. The difference between the emitters won't cause major problems, but the Tekmar should be set to proper setting. The difference is how long the emitters are able to release latent heat into the home. Cast iron baseboard holds a lot heat in the water volume and in the cast iron...

 

every single person that looked at my system said it's cast iron and i'm lucky to have such good heat. Though to be honest, i dont know the diff .They do stay hot for hours.

can you tell from this:

http://i371.photobucket.com/albums/o...s/IMG_2154.jpg

http://i371.photobucket.com/albums/o...s/IMG_2153.jpg

 

Yes, that is correct.

Al.

 

Yes, cast iron baseboard. May not stay hot for hours but it does give a more consistent heat. They take longer to heat up and longer to cool off. And much of the heat is radiant, not the 'heat the air' type (fin-tube).

Also have CI baseboard here. Lately I've been playing with constant circulation. It does make it more comfortable as the baseboard temperature doesn't change as much. I think I'm getting off topic here...

Al.

 

These are fine for what you've got.

 

one thing i keep forgetting to mention is the DHW to the bathroom (longest run) is much faster now. Unsure why this is though. Maybe the old coil was all clogged up? This also means faster HW to the kitchen too which makes me happy. Nice unintended benefit of the upgrade

it's over 60 here today and the heat did go on once...it was pretty cool seeing target temp being the min. of 125! amazing.

 

The coil is like a long pipe run, lots of flow resistance to the water flow! Even when new, they would restrict water flow. Yep, its near 60 here too. Wish it would stay there for the next three months

Pete

 

NO..get cold and expensive! when oil dropped from my previously figured out cap of 5.09, i had an 8 year or less payback on the new system. Now that oil is less than 1/2 that, i'm up to a 16 year payback period

just kidding..love the system and if it's ever set up right will love it more. I'm even starting to understand it And the best savings of all is less/no oil usage so 70 degrees c'mon!

 

It reached SIXTY EIGHT! here today ... I worked outdoors all day in my tee shirt ... (oh yeah, I had pants on too... perverts...)

I had a fill up yestiddy... A buck seventy five / gallon ...

Sorry off topic ... just the way it is sometimes!

 

I need your opinion. Just called the installer and I said he can come out next week when i have a day off but he's unsure of his schedule. He said he did talk to someone and found the proper relay to use for the delay. (that's supposed to stop the short cycling by purging when there's a call for heat)

But i told him i still have the BOOMing. He said he installed the same system this weekend on another house and their factory setup is fine. I said i still smell oil so it's not fine here. He then said he thinks it may be because too much draft and i need a chimney cap.

any truth to that?

 

separately, i told him the sensor read 45 yesterday and today and the min temp was the target temp (125) and it took over 2 hours to raise the house one degree. He told me if i think it needs to be higher then raise it to 130. The thing is, i swear i had temps like 40s before and the target temp was a lot higher. Is it possible the tekmar changed the target temp for a 45 degree day?

and what's more efficient..letting it take the house 2 hours at 125 to heat that one degree of jack up the water temp a bit so it reaches it sooner?