Joined on September 9, 2009
Last Post on August 19, 2014
@ August 19, 2014 12:12 AM in Is 100k BTU the right size of boiler (or HTP heater) for both baseboard heating and indirect DHWyour 61k/44k boiler seemed to be sized correctly on paper, but in real life was it cycling even on a design night? Some in the know here have reported boilers correctly sized to the load with a correctly figured heat loss still cycled up to 50% on a design night. Point being there is a bunch of fudge factor in the heat loss.
SWEI makes 2 good points, 1 being look at the minimum firing rate over max rate, & 2) up size the indirect rather then up-sizing the boiler.
any chance that fur-nasty might go away & an air handler might be installed? you might pre-plan for a 2nd boiler to be added in the future. 2 CI boilers can be staged to modulate & 2 mod-cons would have a 10 to 1 turn-down
If you decide to go with a correctly sized CI boiler, you might try a reverse indirect like a "turbo max". It acts like a buffer & makes hot water. I have one installed in my rental house, works like a charm. I have long boiler run times, long boiler off times, & plenty of hot water for showers after skiing. kinda kills 2 birds with 1 stone, gives you happy boilers (no short cycling) & give you lots of hot water
you have lots of work to do to get it right.
@ August 7, 2014 6:43 PM in Help...I bought a foreclosureIf you could post a picture of the writing on the tubing, that would allow confirmation of the correct tubing.
Don't be tempted to oversize your boiler, the slant fin has a big fudge factor built in already, there are plenty of stories on the wall regarding modulating boilers running at way less than 100% on the coldest day of the year with a properly preformed heat loss.
I've read stores on the wall about people that have been happy with adding the maximum baseboard so the boiler can condense 90% of the year. Play with the baseboard lengths & see if you can get the supply temps down. You could also run a Taco BumbleBee on a 20* delta T, that helps keep the return water temps down & increases your efficiency.
Plenty of good ideas here on the wall.
You have an opportunity to spend a little more & really have a nice system when you are finished.
@ June 18, 2014 9:57 AM in Help with RTU replacement......So I called the 9 Doughnut guy, & asked him if he could also bid a Lennox &/or the AS/Trane units, WAY more was his reply, I"ll get back to you was my reply. The 16 Doughnut man wanted to see the 9k bid just to make sure we were apples to apples, we were, & he went to his supplier & got a WAY better price, dropped his labor some too, & got the job.
Thanks for all the input guys,
@ June 6, 2014 5:59 PM in Help with RTU replacement......So, I take it the Goodman / Daikin unit isn't the top of the line...
But since its national "Doughnut Day", & not to talk price, but...... so lets say the Goodman unit is valued at 9 doughnuts installed & the AS/Trane unit is 16 doughnuts. I'm just wondering if the difference in doughnuts in the cost of the units or in the cost of install & does that increase seem worth it in the long run. again they both appear to be spec'd right, yes both are 2 compressor units both are 2 stage heat, both are installed on curb adapters with permits & tax included.
I'm in the Tire business, & Mr Customer while both of the tires seem black & round there really is a difference in the tires, the china made 90.00 tire will wear out WAY faster than the Goodyear 160.00 tire to put in tire guy terms
Thank You for your input
@ May 31, 2014 9:08 AM in Help with RTU replacement......I researched the Daikin unit further, & found Daikin purchased Goodman. The unit quoted is a re-badge of a Goodman RTU. The goodman number would be: CPG0902103****
What experiences has anyone had of Goodman RTU's????
If its a solid unit, I would feel comfortable having it installed.
@ May 30, 2014 6:06 PM in Help with RTU replacement......The building originally had an airtemp unit from the mid 70's. Lennox unit went on in 2003 with formed duct work to meet the original roof penetration.
both contractors are using curb adaptors & getting rid of the exposed ductwork on the roof.
whats the quality like in the Daikin DCG series??
@ May 30, 2014 3:05 PM in Help with RTU replacement......Yep, its apples to apples on the roof, includes tax, permits - everything.
Is there a big difference in quality between them?
Thank You for the reply
@ May 30, 2014 12:08 PM in Help with RTU replacement......Hi,
I'm usually in the main wall or radiant section but I am faced with replacing my RTU due to hail damage, (can no longer comb the fins without breaking them).
One contractor is quoting an american standard/ trane unit AYSC092F3EH & another is quoting a Daikin DCG090210B. Both are similar in capacity & specs from 2 reputable contractors. There is a BIG difference in price though, like the A S unit is almost double the Daikin.
i am looking for some input as to the quality & reliability & which unit is a better choice long term, I own the building also.
PS both units will be installed with Hail Guards so this doesn't happen again.....
Thank You in advance for your input
@ May 24, 2014 2:43 PM in Help diagnosing hydro air problems....REPLY TO SNOWMELTS POST:
I agree on adding a zone control, wiring is simpler & cuts down on the technician check out time on a service call, its either black or white as to which zone is calling.
Taco ZVC404-EXP gives priority to hot water & has ability to add boiler reset if desired.
Taco ZVC 404 if basic unit wanted.
Clammys point of a more knowledgeable contractor is worth noting too....
@ May 22, 2014 3:23 PM in Help diagnosing hydro air problems....From Snowmelts reply:
"Where are you hose bib with shut off on supply , they should be on return"
any possibility that the guy who re-plumbed the boiler piping is using the old returns as the new supply?
That would explain why its so hard to purge that zone
@ May 22, 2014 12:25 PM in Help diagnosing hydro air problems....1) why is there a washing machine hose between valve 1 & valve 3 ?
2) looks like there is a air bleed in the attic, you can just see it in the middle picture. IF ITS WORKING, it would be easy to bleed out any air in the system IF there is enough pressure in the system. see icesailers post on pressure. verify pressure with an adaptor on 1 of the bleed valves.
Here is an example of a 60 psi gauge:
that you could install the 60 psi gauge on this adaptor (200 psi is way out of range for a boiler)
3) the 28000 btu load seems more realistic than the 60000 number, & its a lot easier to get 28k through the 3/4 pipe.
@ May 19, 2014 12:08 PM in Time to pull the triggerBeing as you are over-sized by a factor of 2 even in worst case scenario design day with one of the smallest Mod-Con boilers made, you might compare & contrast the cost vs benefit of a small buffer tank in place of the LLH. Mine absolutely eliminates short cycling & give you LONG run times & LONG off times.
Just another concept to keep you up at night thinking about.......
@ May 17, 2014 10:43 AM in Time to pull the triggerWhat are you doing for hot water - shower, washer, dishwasher ?
What is your heat loss on the building?
@ May 12, 2014 2:55 PM in RTU vs Mini SplitsHi, I'm new to the A/C section.
We are contemplating a repair vs replace for our Showroom RTU damaged by a recent hail storm, our present RTU ratings = 090 A/C & 200 2 stage heating.
The Condenser coils are damaged beyond reasonable repair by hail, HVAC guy is quoting 2 ways, (1) replace Condenser & (2) replace complete RTU.
The Replacement RTU would probably be similar in efficiency as our present one (2002 installation)
As a 3rd option, i was wondering about just adding 2 properly sized Mini Splits to our existing showroom & leaving the perfectly fine heating side of the RTU to just heat the space.
It seems to me the mini splits are way more efficient than the RTU in AC mode.
I thought I would get a preview here befor I talked to my A/C guy, I don't feel there are many mini splits installed in the KC area.
Thank You for your thoughts,
@ May 10, 2014 12:18 PM in Looking for suggestions in tweaking the design of a buffer tank:Wow, HR, that is a crazy tank. One thing that helped my systems, by adding the ESBE Thermic using a 140* stat element. It loads the tank with steady supply of 138* water (no need to go higher in my system using ODR & injection for in floor radiant). Before the ESBE, the 007 over pumped & the oversized boiler ran cool for 90% of the heat calls. Now during shoulder season, the boiler might only fire a couple times A WEEK......
The OP wouldn't need the ESBE if converting to a modcon I believe, but with a CI boiler they are simple, effective & bullitproof
@ May 9, 2014 9:18 AM in Looking for suggestions in tweaking the design of a buffer tank:Fellow HomeOwner here, I too added buffers to my CI Boilers (2 houses) to eliminate short cycling. Boy It worked like a charm. but remember, the whole point of a buffer is to add volume (mass) to the system, a 'battery' to store hot water if you will. In order to do that, you must use as much of the tank as you can, filling it up with hot water while taking cool water out to the boiler. So hot from the boiler in at the top, cool back to the boiler from the bottom so when the buffer is 'full' of hot water the load can use that water in the buffer to satisfy the heating demand without constantly firing the boiler.
@ May 2, 2014 9:34 AM in ShowerWatching This Old House last nite, Tommy designed a shower with heated walls & floor. He was quick to point out a flat ceiling would condense and drip cold water on the person in the shower, the solution, why a slightly sloped ceiling so the drips would run to the the wall.
@ May 1, 2014 5:22 PM in Time for an upgrade/retrofitMine & yours will hookup different because of where the pumps are on our respective systems, but the concept will be the same.
Look at the diagram labeled "Piping Orientation", "Return Mounted" on page 3 of the datasheet. My circulator is mounted on the supply piping (top placement), where yours is on the return bottom placement labeled: other location for circulator.
The key is to get the thermic installed in the return line that way the boiler can just recirculate its own water until the temp gets over 140* ant then it will start to supply some hot to the system as it keeps the boiler above 140
@ April 30, 2014 1:03 PM in Modifications to Hydronic SystemI was looking at the instructions on the IsoTherm, I have concerns about its appropriateness for your design.
under: "Primary / Secondary piping" "To ensure proper operation and to prevent ghost flow conditions, a primary/secondary piping arrangement is required..."
if I am reading your diagram correctly, thats not how it would be hooked up.
It does appear to be reasonably priced, but an i-valve & Alpha or BumbleBee might be a better choice with ODR & an ECM motor for low cost of operation & steady temps.
Good lock with your re-pipe,
@ April 30, 2014 11:47 AM in Time for an upgrade/retrofitI have taken my 2 cast iron boilers through sawzall surgery, & used the ESBE on both, It works like a charm, I'm sure my boilers thank me every day.......
Here is what they look like:
@ April 24, 2014 4:52 PM in What's your opinion on this design...My last sawzall surgery in my 2nd duplex I Installed a TurboMax 44 combination buffer & DHW. WOW I like it, It has very LONG run times on the boiler & makes gobs of Hot water for the after ski showers. A Honeywell AMX tempering valve limits the DHW temp. TurboMax makes an Indirect with 4 boiler water tappings especially for use as a buffer, but after a call to their tech dept, they told me how to use the tappings on the air bleed & tank drain to plumb in a tekmar 361 injection for the infloor radiant. An esbe Thermic protects the boiler from low return temps.
Looks like your system would be a natural for this, substitute the iseries 3way or 4way for the tekmar injection & run the baseboard off boiler temps, you could even add an inexpensive boiler reset to vary the boiler temps from say 140* to 180* or some such.
I used an alpha on my radiant side, but the "B" looks interesting too
@ April 6, 2014 3:58 PM in Indirect or Combo Boiler with Recirc DHT?Terry,
I reread the whole thread, & I think you have more to do to get the max efficiency & more importantly comfort from your system.
Please post Pictures of your boiler & near boiler piping please.
If I read your descriptions correctly, I think you have boiler temp water circulating through radiant tubing. This is bad if its so. Max temp for tubing is in the 140* range, & you reported boiler temps in the 160 to 200* range.
that is how my system was piped when it was installed, it was not kind to the boiler or the tubing.
The goal would be to get just the right temp through the tube with a low wattage pump in constant circulation.