Are my cycle times too short?

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  #41  
Old 12-18-13, 06:29 PM
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Here are some photos. I definitely have the correct pipe! The HL is currently set at 182, and the boiler heats up a little more after hitting the HL. Also, the thermocouple has about a 1-2% error at this temp, so that could explain why you're seeing 192.
 
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Old 12-20-13, 01:40 AM
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cdbma,
Just a couple thoughts and looking at pictures. I don't know how much it effects it and when. What size is your output and return pipe/manifolds? My WBV-04 tapping is 1.5" out, 1.25" return. I was only 2 zones prior to adding my superstor and the new zone. Mine was originally reduced down to 1" out and return. I don't know if it was NJtrooper or others that recommended when I add on to keep the out at 1.5" and reduce the return from 1.5" to the 1.25" as close as possible to the return inlet. There might not be enough water volume moving (or too much head pressure) when all the zones are on.

Not sure if I asked but how is it all controlled? My superstor has priority control through the Taco 506. If I need hot water the other circulators don't turn on. Maybe a conflict if all 4 turn on in the AM when you shower and it's trying to heat from setback.

Do the thermostats conflict with the heat manager? First post you say they are set to 3 cph. My understanding is that they won't run more than 3 times per hour at that even if room is cold. They try to adjust so heat calls correspond to satisfy and run longer. Now that it's colder maybe it needs more cycles especially if there is flow constrictions and three are trying to anticipate and satisfy. Maybe no cph limit setting just a slightly larger temp swing 2-3 degrees rather than .5-1
 
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Old 12-20-13, 04:59 AM
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I can certainly take some measurements, but I'm convinced that the two variables that changed - the Beckett unit and thermostat - are behind the short cycles. Of course, I can't prove it...yet! I have already disabled DHW Priority, so I have heat in the morning. I have plenty of hot water, so no need to prioritize that zone.

I got up early this morning to watch all the numbers. The boiler cooled to about 138 overnight. I had three thermostats return from setback at the same time. The Heat Manager had economized to 144. Circulators turn on. Boiler starts to cool down (heading down to diff limit). Diff limit is hit, and boiler kicks on. Now it's a race to hit the high limit, which may be changing in real time, as the HeatManager decides that a larger high limit is in order. I see that happen. Some cycles reach the new high limit, so the boiler turns off. If the HM then decides a new high limit should be set, the current boiler temp could now be less than the HL-diff, so the boiler fires up again immediately. And so on, and so on... I can certainly see a number of small cycles possible as the HL changes. If the algorithm would just give up and say "crap, I need to reset to HL," I'd get a nice long cycle!

So, I've concluded that the short cycles could be a side effect of the thermostat setback, and the HM dynamically resetting the HL. If the intermediate HL increases enough to trigger the differential algorithm, the boiler turns on. This could happen at any time, depending on how quickly the boiler cools off and how much higher the new HL is set. As sequoiasoon mentioned in a prior post, it's working its way up the HL "ladder" until it reaches the preset HL. I turned off the HM for a bit, and, of course, the boiler stayed on until HL. It ran for about 8:30!

Ideally, I'd like to have the HM temporarily disable itself when I'm in setback and let 'er rip to HL. I'm going to get there anyway!

I am in two setback scenarios every weekday. I have a setback from 8:15pm to 4:30am, then 7am to noon. Lather, rinse, repeat.

sequoiasoon - I have dropped my CPH from 3 to 2. I will monitor for a few days to see if that has any effect.
 
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Old 12-20-13, 09:00 AM
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I got a reply from Beckett. The scenario as described is what the dynamic function of the heat manager is. Basically working similar to an ODR where it tries to use the lowest temperature to heat the house so will always look to lower the HL.

"Thanks for contacting Beckett. We are aware of the abnormal temperature reading you are seeing in the history menu of the AquaSmart. It is currently being addressed by the engineering department. The problem is mathematical error in the history function of the control, however, it does not affect the functionality or operation of the control.

Sorry, but there is no function that determines "real time" efficiency gains. As you suggested annual fuel usage totals will be required to provide that information. Increasing your high limit differential will increase your burner run
time as long as the call for heat remains."

I had inquired about why my numbers had 400+ degree "avg" and if there was someway to show overall efficiency like the Intellicon. Also if the many lower cycles effect anything.

I'm torn on what to do, utilize the HM (for the year and check fuel usage) or install my Intellicon that I had purchased prior to buying the Aquasmart. My friend's Intellicon that he installed on Halloween is saying he is at 34% avg savings. His HL is 180, no LL, Intellicon LL is 135 with 1.5hr max hold/econ. He does not have an indirect or tankless and uses his electric water heater for domestic. He had installed that way back when his old boiler was having problems supply hot water. The Intellicon will economize down to the 135 pending how fast temp drops but when heat call will "let 'er rip" to 180 everytime if there is continued heat call.

The Intellicon didn't work for NJT in the past and is not for everybody. On my hold house when installed it said I was saving about 30% and sure enough my usage went from 1000gal to 700gal over the course of 1 year.

The cph....I don't have that feature so can't help but imo if it's real cold and rooms are dropping temp (or not coming up in time) why would I want it limited? My "limit" has an extra feature called father-in-law that opens the bedroom window, leaves bedroom door open, and leaves for 3 hours when it's 20 degrees out. Throws cold air right over T-stats and wastes my money and heat out the window. I feel like my parents and have my wife yell at him "shut the &^%$ window and door" "it's cold out!"" do you live in a barn"
 

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  #45  
Old 12-20-13, 09:49 AM
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Originally Posted by cdbma
Also, the thermocouple has about a 1-2% error at this temp, so that could explain why you're seeing 192.
Does your TC accessory have its own battery supply? If your batteries are fresh I would trust your meter/TC over the boiler gauge.
 
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Old 12-20-13, 01:05 PM
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Interestingly, my TC, Beckett, and boiler thermometer are pretty much in agreement - plus/minus a few degrees...close enough for me.
 
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Old 12-21-13, 11:19 AM
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Outlet pipe looks to be 1 1/2" or so - I really don't want to make a mess by peeling away the pipe insulation.

Interesting observation: If all three zones are active (circulators running) and I'm warming up from a setback, I see the lower temps in the FR zone (150s range). If the FR zone is on by itself, the temp of the TC I have attached to the pipe matches up with the temp on the Beckett and boiler.
 
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Old 12-21-13, 12:01 PM
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If all three zones are active (circulators running) and I'm warming up from a setback, I see the lower temps in the FR zone
I wonder if the way the system piping is laid out if it is possible that you are getting 'backflow' in the FR zone when the other zones are being pumped?

FR zone is at the 'ends' of the manifolds, isn't it?
 
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Old 12-21-13, 02:02 PM
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I believe I see backflow preventers. Let me take a few more photos...

the FR loop is in the middle.
 
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  #50  
Old 12-22-13, 04:37 AM
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NJT,
I managed to get to the basement this morning before one of the zones was flowing water. It was cold. So, I know that one is not having flow control issues. I need to get up early again before the FR zone kicks in (or put the thermo on hold) to verify that its flow check is working, but I have no reason to believe it's not.

Of course, in the middle of all this testing, it decided to get warm (not complaining!), so the house is quite comfy this weekend, with the boiler essentially off (or running at a much lower HL). Happy to save oil!

Stay warm. Enjoy the holiday season. I plan to stop obsessing about this for a few days so I can kick back and enjoy the week with my family. I hope that all the forum members are able to do the same.
 
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Old 12-22-13, 10:27 AM
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It's 70° here right now. My boiler has not fired once since yesterday morning! CRAZY! Gonna get cold tomorrow they say.

Let me explain a bit more about what I was thinking...

It may not be possible for this to occur... because for ANY backflow to occur the pressure differential would have to close the flow check valve... but this is what came to mind...

WHAT IF:

All three pumps running, the other two 'overpowered' the FR pump and caused that zone to run in reverse?

Is it even possible? I don't think I've ever heard of it... but it's always wise to 'entertain' an idea without 'accepting' it, and before 'dismissing' it.

Are the control knobs on all the flow checks in the correct position?

In the picture, the one on the right, it appears that the knob is a little rusty. Is it leaking around the stem?

I plan to stop obsessing about this for a few days so I can kick back and enjoy the week with my family. I hope that all the forum members are able to do the same.
OK, good idea! Have a happy one!
 
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Old 12-22-13, 02:42 PM
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In the picture, the one on the right, it appears that the knob is a little rusty. Is it leaking around the stem?
Wow - your eyesight is good! Yes, there is a bit of rust around the valves for the two first-floor zones. I don't see any active leaks. I'm not sure if they're in the right position, but I'm afraid to mess with them in the middle of the heating season! I am going to get a real good look tomorrow morning when I [gently] brush away the rust. If they were leaking, I may not see water due to quick evaporation on the hot pipes, but I'll look for traces of minerals, etc. I think I can also get a close-up shot for you.

Is there any way to verify the correct position without trying to move the stem? If the stems are indeed bad, can they be replaced or does the entire valve have to be replaced?

I like your idea about the other two zones overpowering the FR zone. If that's the case, it's been doing it for 20 years! Arg... Come to think of it, the first "branch" is for the upstairs zone. It splits into two runs - front and back of house - then back to one just before the circulator. It may be hard to see from the photos, but that pipe is larger than the first floor zones. Not sure if this is relevant - just thinking out loud. The FR is the next branch, and the other first-floor zone is the third branch.

Didn't I say I would stop obsessing about this? Oh well, typical homeowner!
 
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Old 12-22-13, 04:27 PM
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NJT,
Valves look ok. They were covered with dirt, dust, and general crud. That rust on the right valve was limited to the thumb screw and came right off with a gentle nudge with my brass wire brush. I see no signs of leaks/weeping, etc. All three screws appear to be turned down all the way. Will monitor.
 
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Old 12-22-13, 05:53 PM
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There may have been some 'weeping' at the gland nut at some point.

I agree not to mess with to any great extent... but you could try just 'snugging' the 'gland nut' just a wee tad to squeeze that packing a bit around the stem.

Do you think those valves are older than like 1991 ?
 
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Old 12-22-13, 07:29 PM
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I'll try for a teeny bit of tightening. At this point, "if it ain't broke..." I have no problems messing with the nut - or even replacing the guts - when I just need the boiler for DHW! I will lose bonus points from my significant other if we go cold!

House was new in 1994 when I moved in.

I noticed on the Taco site that the guts have been redesigned. I wonder if they did that because they leaked! I have to 3/4" valves that were messy. Interestingly, the 1" valve on the other zone is squeaky clean!
 
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Old 12-22-13, 07:59 PM
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At this point, "if it ain't broke..."
I'm down with that. I don't think you can break it though by just snugging that gland nut. But it's not leaking now that you know of, so yeah, leave it alone.

I noticed on the Taco site that the guts have been redesigned. I wonder if they did that because they leaked!
I don't think so.

I would venture to say that almost every single valve I've ever installed has had to have the gland nut tightened just a tad. I believe that the manufacturers ship them on the loose side. Gland nuts should only be tight enough to not leak.
 
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Old 12-23-13, 04:41 AM
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Here I am, continuing to obsess, when I said I wouldn't! Alas...

This morning, I conducted an experiment. I got all three zones running, then turned off two, leaving the FR as the only zone pushing water. Guess what? I could see the temp rise immediately - about 4-5 degrees. More importantly, it was within a few degrees of what the boiler temp gauges (beckett & boiler thermo). Turn on the second floor zone, and the FR zone pipe temp immediately starts to drop. However, yesterday, I did note that, when only one zone was running, the other pipes did not appear to be warm, so I'm still thinking that the flow checks are functioning.

Here's another thought. As I've mentioned previously, the first branch is the second floor. It's a big zone, with a 1" pipe running the length of the basement, then up to the second floor master, where it splits into two 3/4" runs - one across the front of the house, the other across the back. In the front run, it covers the master, a guest room (not occupied), and my daughter's room (not occupied), then back to the basement. The back run heats a walk-in closet, master bath, second bath (not occupied), and finally my second daughter's room (not occupied), then back to the basement. The two runs join up just before the circulator. What I mean by "not occupied" is that I've done everything to prevent the baseboards from providing heat. I have the louver closed and the bottom is plugged with pipe insulation to limit convection. Bottom line is that these rooms are quite cold in the winter.

So, is it possible that the water returning from this zone is really cold (colder than the other zones - especially when coming out of setback), and when mixed with the other zones, is just too much for the boiler to heat in the short time it passes through?

Assuming the flow checks are working, it just seems to me that the second floor zone is being a "hog" with the water, almost like reduced water pressure in the shower when someone flushes.

Ok, now it's really bugging me!
 
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Old 12-23-13, 08:38 AM
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is it possible that the water returning from this zone is really cold (colder than the other zones - especially when coming out of setback), and when mixed with the other zones, is just too much for the boiler to heat in the short time it passes through?
I don't think so... you've said that the boiler has no problem outputting 180 water I believe?

It IS entirely possible that you are exceeding the recommended flow rate of the boiler though.

Have you measured the temp rise across the boiler under various conditions of zone openings?

I would think that if the boiler can't achieve at LEAST a 20F Delta T from return to supply that it is being overpumped.

it just seems to me that the second floor zone is being a "hog" with the water
A more reasonable possibility. It could be that that the FR zone is operating at higher 'head' and the pump is already operating toward the left side of it's curve, and when the other pumps are running simultaneously the FR pump has to fight with them for it's share of flow... and seems to be losing the fight. It's two against one against an already handicapped opponent!

Does the same thing occur when only one or the other of the other two zones is calling? Or do BOTH have to be running for this to occur?
 
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Old 12-23-13, 08:58 AM
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The FR zone seems to be most impacted when the second floor zone is active. I can easily do a test with the other first floor zone. Stay tuned!

As for temp rise, are you asking me to measure the water temp entering and exiting the boiler? If so, do I pick a zone (FR?) and check on both ends? Should I assume you want me to have all three zones running?
 
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Old 12-23-13, 09:25 AM
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As for temp rise, are you asking me to measure the water temp entering and exiting the boiler? If so, do I pick a zone (FR?) and check on both ends? Should I assume you want me to have all three zones running?
Only if you want to be more OCD am I asking...

Yes, RETURN to SUPPLY, right across the boiler. I would think the most telling would be if all three zones are running.

Basically, if you are over-pumping the boiler, you will see a lower DT across it, and it will 'struggle' to come up to temp. This should be measured when the boiler is near high limit to have any real meaning.

I don't think it's got anything at all to do with your current line of "WTH?" though, just a curisosity at best.
 
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Old 12-23-13, 09:37 AM
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Ok, just came back up from taking some samples and read your reply. I think I have something you can chew on.

With the second floor zone not circulating, I activated the second zone on the first floor. I did not see change in the FR zone (out) temp. However, when I activate the upstairs zone, I can see the FR temp drop 5-8 degrees almost immediately. When I turn the zone off, I can see the temp come back up - and it then tracks the boiler/beckett reported temps quite closely. It's clear to me that the second floor zone is having a big impact.

All three zones on. Boiler @ HL of 182. FR temp out: 164. FR temp in: 153. Turn off two zones (most importantly, the second floor): FR temp out: 188 (boiler was at HL + a little overrun - 188 matched Beckett temp exactly). FR temp in: 153. How convenient.

Now what?
 
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Old 12-23-13, 01:47 PM
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NJ Trooper,
Is there any big impact with the FR returning at the far end of the return manifold and only 3/4" compared to second floor 1" being closest to inlet/return?

cdbma,
if you move some of the insulation at the return manifold the fittings should have size markings on them 1, 1 1/4 etc. From the picture I see it looks like they put a reducer bushing, close nipple, T, and then tapped the indirect return into it. Not sure what else might have been done that might impeded flow.

Learning from NJT words of wisdom to others, I tried to make sure i had good flow everywhere. I bought all long turn 90's for all my copper, kept my black piping 1 1/2 for as much as possible etc. I don't know why Peerless made mine (and probably yours) 1 1/2 out, and only 1 1/4 return (never mind the drain and pressure relief in the back of boiler)? My Weil McLein had 1 1/2 on both.
 
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Old 12-23-13, 02:39 PM
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I've enclosed some photos of my "bare nekkid" pipes. Out and return are all 1 1/4". Left (2nd floor) is 1" return, with the other two 3/4". I also took a pic of the indirect return.
 
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Old 12-24-13, 04:43 PM
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Did some more informal testing today. I'm 100% certain that the two 3/4" runs don't impact each other and quite certain the larger second floor piping does. Short of a full reconfiguration (not in the cards right now), I don't see any options except stagger the zone restarts after setback (easy) and/or increase the boiler temp (costly).

While I have you all - and I have photos of my config (one more added here), I would appreciate some instruction on how best to bleed the zones should I need to do so in the future. As you can see, the circulators "pull" and I have ball valves for all three zones just after the expansion tank. Oh, the two pipes on the left that merge are from my second floor "split" zone. I have no idea what that ball valve is there for.

I know you are all busy with members' problems that are much larger than mine, so please treat this request with the low urgency that it deserves! I must admit that I am following NJDave's problem like a good mystery...totally sucked into this one! I think NJT is close to finding the "killer."

Logging off to wait for Santa. Have a good one!
 
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Old 12-25-13, 11:26 AM
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All three zones on. Boiler @ HL of 182. FR temp out: 164. FR temp in: 153.
What seems strange here is that you are indicating a DT of only 11° on the FR zone. This generally indicates too much flow, or not very much radiation on that zone.

On the other hand, if the large zone IS 'hogging', and there is next to no flow in that zone at the time, then I suppose that the temperature across the zone could have 'equalized'. DT readings are only applicable when water is actually flowing. If you shut off flow to a zone, in a short period of time the DT would go to zero.

Turn off two zones (most importantly, the second floor): FR temp out: 188 (boiler was at HL + a little overrun - 188 matched Beckett temp exactly). FR temp in: 153.
What's strange here is that your return temp hasn't really changed as we might expect it to if the zone were getting full flow. Did you give the zone enough time to circulate the 188 water all the way around the loop before reading the return temp?

Is there any big impact with the FR returning at the far end of the return manifold and only 3/4" compared to second floor 1" being closest to inlet/return?
It sure looks like that. Big zone hogging the flow.

I would appreciate some instruction on how best to bleed the zones should I need to do so in the future. As you can see, the circulators "pull" and I have ball valves for all three zones just after the expansion tank. Oh, the two pipes on the left that merge are from my second floor "split" zone. I have no idea what that ball valve is there for.
"Bleed" is different from "Purge". Bleeding means opening up the little 'pee' bleeders on the baseboards, radiators, and letting air out. Purging means pushing water and air through a zone at a faster rate... which should really only be done with a new system for initial filling, or when there is no other way to get rid of an air bubble.

The ball valves below the drains on the big zone are used as a 'detour' to the water when you need to purge those zones. By closing those ball valves, and putting a hose on the drains above them, when you open the drains the water is forced to travel through the zone rather than take the shortcut through the boiler up through the pump and out the drain with little to no flow going through the zone.

As far as that goes, the drains on the two zones to the right with no ball valves under them are pretty much useless...

"Become the water" and think about what path you would take if there were an open drain to exit from.

Remember that water ALWAYS will take the path of least resistance from a higher to a lower pressure. An open drain is always the point of lowest pressure. An open feed valve into the system will be the point of highest pressure (when there is a drain also open).
 
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Old 12-25-13, 11:27 AM
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By the way... mice almost never cross an open floor space... they always travel along walls... traps are better placed along a wall rather than in the open.
 
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Old 12-25-13, 06:09 PM
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Yea, I meant purge. I have no reason to believe I have air - no noises, etc. I'll have to digest your observations and questions a few more times before I can answer and/or conduct more experiments. At this point, I know that about 8-10 seconds after I stop the flow of water to the second floor, the FR pipe temp starts [quickly] climbing. Once it appears to reach its max, I can start the flow again to the second floor and see the FR temp start to drop. It's repeatable.

As for the trap, I consider myself an expert in catching them! This trap was kicked when the boiler has its annual maintenance. I never returned it to its rightful place. A few years ago, I decided to put out small bait traps OUTSIDE the house to see if I could get to them before they got in. It seems to be working. However, I do keep a few baited traps inside for those adventurous ones!

I'll re-read your post and try some more experimenting. HNY!
 
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Old 12-25-13, 06:21 PM
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NJT, I don't follow your comment about about the return temp not really changing in the scenario where I have the second floor off. Out temp is 188, return temp is 153. Seems like it's giving heat to the room. I thought a reasonable delta was 20...yes, this is more. Bad thing?

I'm very good at following directions. If you have a series of steps you want me to perform, I can do that and report back.
 
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Old 12-25-13, 08:35 PM
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I don't follow your comment about about the return temp not really changing in the scenario where I have the second floor off. Out temp is 188, return temp is 153.
In the first example, with big hog zone running, you said the supply to the FR was 164 and the return was at 153.

When big hog was turned OFF and only the FR was running, you said that the supply to the FR rose to 188, yet the RETURN WAS STILL THE SAME.

If the water going INTO the zone is about 20+ degrees HOTTER, shouldn't it follow that the RETURN WOULD BE ALSO?

I was asking if you waited long enough for the hotter water to make it all the way around the zone and register on the return thermometer... or if you read it right away?

I thought a reasonable delta was 20...yes, this is more. Bad thing?
It's not necessarily a bad thing if the area is heating properly.

Most baseboard systems are designed for a 20 delta T. This means that with the proper flow on a 3/4" zone and appx 66' of fin tube baseboard, you would get near that 20 delta.

If the water if flowing FASTER, the delta would be less, and vice versa for SLOWER flow. This is because with the water flowing faster and not spending as much time in the baseboard giving up it's heat, it would not have as much time for the water to cool... and vice versa if the flow was slower.

The amount of baseboard installed affects the delta also... the more baseboard, the more heat is removed from the water and into the room.

There's formulas for all this, but I'm not going to go into that at this point... because there's really no point...

I was just wondering why if you had hotter water going IN, why don't you have hotter water coming OUT (of the FR zone)?
 
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Old 12-26-13, 05:09 AM
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Ok, got it. Makes sense. Eggnog hangover! I thought I waited until the temp stabilized, but perhaps not. Your point is enough to get me to do this again and wait for the water to fully circulate.

I'm sure you agree that, at this point, it's a nice academic discussion, but it is what it is - unless I'm willing to make some changes to the configuration. Now that I know what's going on, I think I can stagger zone restarts [from setback] to "balance" the zones. Also, when the FR zone kicks in form setback in the afternoon (when we both come home from work), the second floor zone is still in setback, so the "hog flow" situation is not in play. The only real issue is first thing in the morning, when all three heating zones and the DHW zone are active.
 
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Old 01-17-14, 01:38 PM
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more info to share on possible short cycling issues

Some new information to share. I had a long chat with a Beckett tech rep, and he confirmed something I was seeing. In a nutshell, the boiler appears to be outrunning the AquaSmart's dynamic HL setting.

The boiler should run until there is an end to call for heat, or HL is reached. However, with the AquaSmart, HL is dynamic. As you know, it tries to set the lowest HL it can and still keep the house warm. After watching the cycle start in the morning, I've discovered that the boiler can hit the current HL (as set by the AquaSmart) before hitting the "hard" HL that I've programmed in. If the boiler temp reaches the current HL, the boiler stops firing and sits there for the duration of the differential. Now, the water temp is now cooling off and the AquaSmart will continue to increase the HL (albeit slowly), so both sides contribute to getting to the "HL minus the differential" temp. Still, the boiler is off while this is happening. Then, the boiler fires again and chases after the latest dynamic HL. If it catches up, the boiler shuts off again. The Beckett tech confirmed my observation and all but conceded that this is an undesired side effect of the device trying to do the right thing. I asked him if I could turn the economizer setting down, but he felt that this might make the problem even worse. He reluctantly suggested setting a low limit, but that clearly defeats the purpose of a cold start configuration. He also thought an ODR could work, but I don't want to spring for the $$, just to find out it really doesn't help. I certainly won't be able to return it.

What I need is for the Aquastat to figure out that it's really cold, and I need it to get to the hard HL pronto - skipping any intermediate HLs along the way, so I don't have to wait for the differential on the way up.
 
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Old 01-17-14, 02:51 PM
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That's what an ODR does very well.
 
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Old 01-17-14, 02:57 PM
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saves - thanks - good to know. My oil dealer wants my left kidney for the Beckett 7600WTM. I'm searching the web for it, but only got one hit. Looks like this is close to a "dealer only" part, but I'll keep trying. This thing is clearly a DIY install.

or...I turn off the economizer setting during the coldest months.
 

Last edited by cdbma; 01-17-14 at 03:21 PM.
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Old 01-17-14, 06:36 PM
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Wireless Temperature Module - Amazon.com

Was the one hit you got at Amazon?
 
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Old 01-17-14, 07:08 PM
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Yikes, that's not a price. That's the national debt! Saw a module for half that price at patriot-supply.com.

Patriot Supply - 7600WTM
 

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Old 01-17-14, 11:48 PM
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For an ODR the Patriot Supply price is not bad (especially when compared to Tekmar etc.) The question is what do you gain in efficiency, non-short cycling, comfort and how long does it take to payback? What are the same answers if you shut down the HM (i.e how much more fuel do you use) that would cover the cost of unit?

I have all the same short cycling issues going on because of the dynamic HL. I don't have the discomfort as you describe in heat for house though. My burn time range from 6+ minutes to only 2 seconds an many 2-4 minute runs. Oversized boiler almost definitely but that is what was there. I’m trying to be good and leave this thing working to see how it does fuel wise for the year but the short cycling just hurts to listen to especially the 2 second fire and shut down ones.

The Intellicon HW+ worked similar but adjusted the low limit/differential which might be more what you’re looking for. When it fired on heat call it would always run to 180. Once HL reached it would run circulators down to 145 (default or you could adjust lower) based on how fast it dropped according to sensor. Faster drop equaled a higher low limit (i.e. 155-160) then run up. Since boiler was cold start if no heat call for heat or DHW boiler would just cool naturally. The unit was like $180 at the time but with fuel savings paid for itself in 2 months. How much would it save over the Beckett who knows, maybe none or use more but might be better for comfort level.

Total side note which I need to post pics of. Do you have the 2 in 1 sensor with LWCO or just regular temp sensor? Last week on the 30 degree day with 4 degree night forecasted I went to wash my hands at about 3pm and water was cold. Boiler had been running perfectly (except the short cycles) since a week before Thanksgiving. When I went to check boiler the LCD said sensor error, I first thought low water but still had 15psi. Read the manual again, shut off power to try and reset but nothing. Now what? I shut off all zones, drained boiler and removed the sensor. When I removed it the end sensor tip fell to the ground. The poly cap nut that hold it had split into 3 pieces but luckily stayed on the threads until removed. How that happened, couldn’t tell you, I never touched it when installed. Out of 4 local supply houses only one had 2 sensors in stock so I got one and replaced it. Now working fine again which was good as it got real cold. I called Beckett and tech said he had some complaints about that but not many. He sent a new one under warranty which is now in my box of spare just in case stuff. Great customer service on their part but if I wasn’t a DIY’er would the local companies have a couple of these sensors on the truck if I had called for help at 6pm or later?

My other back up plan which is still available if needed and maybe if somebody else is stuck. The Aquasmart came with a “regular” temp sensor that installs into the original brass well (though will need some grease or something as I tried and it’s TIGHT). You would still need to drain down boiler etc to swap wells but better than freezing. I also saved my old Honeywell aquastat which maybe I’ll never need BUT in an emergency could easily be reinstalled (with the brass well) in 20 minutes to ½ hour and system be back up and rolling. If you have your old parts, might want to keep them also. If not, a new 2 in 1 sensor is $40 so you might want to pick that up as a “just in case” butt covering.
 
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Old 01-18-14, 05:11 AM
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My burn time range from 6+ minutes to only 2 seconds an many 2-4 minute runs.
This is exactly what I'm seeing on my history log.

I don't have LWCO.
 
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Old 01-18-14, 10:59 AM
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cdbma-

Yikes, that's not a price. That's the national debt! Saw a module for half that price at patriot-supply.com.

I don't know whether we are allowed to bad mouth companies here, but I found that drillspot is ridiculously high. Seems like they are trolling for suckers. Guess not illegal. Just my opinion. Not that i have a wealth of experience, but patriot-supply seems to have very good prices.
 
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Old 01-18-14, 02:09 PM
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All I can say is that if someone doesn't 'do their homework' when shopping on the internet, they more or less deserve to pay what they pay.

Some of the suppliers are charging full retail. It seems that Patriot and Pex both charge closer to wholesale. I was only disappointed once with the latter and they have redeemed themselves in my book, so I always recommend one or the other of them.
 
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Old 01-19-14, 12:36 AM
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I've bought many things from Patriot and always gotten good prices. Bought some things on ebay from them way back because they had like 10k+ feedback all 100%. Then found out they are actually less than 10 minutes from my job so I can do local pick up no shipping. They honored their ebay prices at the counter.
 
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