Heating Help

need flows and heads for each loop

@ May 19, 2013 5:49 PM in Ultimate Goal:

then maybe...

allowance for the vagaries of weather

@ May 19, 2013 11:34 AM in What is the most effective heating system for Schools & Intermittent use buildings?

Would calculate BTUs per degree-day over a period of roughly similar days.  Data from http://www.degreedays.net/ using a nearby PWS is amazingly useful.

I'm surprised nobody's mentioned the new fourth request

@ May 19, 2013 11:09 AM in Order of Catagories on the Wall

hopefully people will read them.

Setback studies

@ May 18, 2013 1:02 AM in What is the most effective heating system for Schools & Intermittent use buildings?

rarely (if ever) consider radiant heat.

Many of us have tried setbacks.  Few have stuck with them, at least to the depth with which we started.

The comments tell the rest of the story...

Looks like the insurance company

@ May 17, 2013 11:06 AM in Lofgren case settles...

or companies wrote a fat check and nobody is officially to blame.  It's just a "freak combination of a bunch of little things that shouldn't have all happened together."

Hmmm.....

I think it depends a lot on water chemistry

@ May 16, 2013 9:52 PM in Longest lasting indirects

Out here in hard water land, the Phase III tank-in-tank designs (Triangle Tube, also relabeled by several boiler manufacturers) hold up better than anything with a coil.  They don't like high chlorides, however.

I started with one of these

@ May 16, 2013 9:59 AM in Burnham has a sense of humor!

$1750 (wholesale) plus $45 per month and $0.45 per minute for the service.  Paid for itself in 3 months.

It depends on the performace of the board

@ May 16, 2013 9:21 AM in Time to choose a boiler

Some dry systems (generally those with more aluminum) are more efficient than others.  Design will dictate what water temperature and how much floor area gets tubing in which rooms.

latent loads

@ May 16, 2013 12:22 AM in Radiant Cooling

are minimal about 98% of the time out here in the High Mountain West.

That should work

@ May 16, 2013 12:18 AM in zone valve question

even with bang/bang zone valves!

Circs instead of zone valves

@ May 15, 2013 8:34 PM in zone valve question

mainly to provide zone by zone flow control.   If I had CCVs and proportional controls I could use a single ∆P ECM circ, but I might still separate out that 40 GPM zone since it represents almost 2/3rds of the total system flow.  While ECM circs can modulate flow, they are still centrifugal pumps, and as such, pay a price in hydraulic efficiency when operated near the bottom of their range.  What does the giant pump do when only one of those 5 GPM zones is calling?

Are there additional downstream control valves?

563-2

@ May 15, 2013 8:06 PM in Hot water recirculation do they save money?

is a snap-on aquastat.  Should not have any contact with water unless something goes quite wrong.

I like the B&G/Laing Autocirc e-series pumps -- dead quiet and ultra low power.

In order to use a momentary contact, you'll also need a double pole relay wired for latch-on:  Wire one set of NO contacts in series with the coil, then wire a NO pushbutton in parallel with those.  Put the aquastat in the same series string.  Control the pump using the other set of relay contacts.  Pushing the button energizes the relay, which holds itself in via the first set of relay contacts until the aquastat breaks the circuit and resets it.

My favorite method is to install a current switch on the AC wire feeding the overhead light  Replace the wall switch with an occupancy sensor and the whole shebang gets automated without even needing a relay.

D'Mand

@ May 15, 2013 6:42 PM in Hot water recirculation do they save money?

is probably the best known.  Taco licensed it IIRC.

You can roll your own without too much trouble.  Pushbutton or occupancy sensor plus a Taco 563-2 will work.

CCV = Characterized Control Valve

@ May 15, 2013 2:45 PM in zone valve question

Basically a ball valve with a special characterization disc which produces linear flow rates based on position.  The first two pages of https://www.belimo.us/belimo/media//Technical_Documents/Characterized_Control_Valve/CCVTechDoc.pdf describe the concept quite well.

Without knowing loop heads, I'd probably spec a single Stratos for the 40 GPM loop and another for the 15 GPM loop.  I'd set those for the most ∆T I could tolerate on those loops at full load.  The 8,8,5, and 5 loops might get individual small pumps (Bumble Bees most likely) or be combined into one or two groups on a ∆P circ with zone valves.

Been waiting for the Android version

@ May 15, 2013 2:18 PM in Slant/Fin heat loss app

and just installed it -- thanks!

how many GPM?

@ May 15, 2013 1:08 PM in zone valve question

really is the question.  Belimo makes good stuff -- I greatly prefer their CCVs over zone valves.

What you are likely missing is the opportunity to tune the flow for each zone independently, which would be trivial using separate ECM pumps.  Adding circuit setters or proportionally-controlled CCVs would probably cost more at those flow rates.

I can control them with a TRIAC

@ May 14, 2013 5:39 PM in Cadet Combi boiler

for under $50, but there's the time and hassle of piecing it together plus the inefficiency of both motor and controller.  Those little ecocircs move water using almost no electricity and the variable speed dial is already there.  Just wish they'd give us a 0-10V input option for them.

The switching power supplies used in ECM circs should be designed to run on 90-250V (like computers have for almost two decades.)  Even better if they extended the uper range to 300V, which would allow use on one leg of a 480 service.

I've been using the Wilo Stratos on 208V here and have not had any dropouts yet.

union circ

@ May 14, 2013 4:27 PM in Cadet Combi boiler

that we can control somehow, preferably ECM, similar in size to the little ecocirc or even the larger one.

hybrid systems

@ May 14, 2013 3:29 PM in Cadet Combi boiler

and the control thereof is what I prefer to build, but I'm always looking for better answers.  We have several times the heating degree-days here as we do cooling, but the challenges for a small house (of which we have many) come from both cost and equipment space.

I wish Daikin made the Monobloc Althermas in smaller sizes.

Affordable boilers

@ May 14, 2013 2:54 PM in Cadet Combi boiler

as you've pointed out before, ROI gets pretty ugly when you're heating only a few months with a small heat loss.

Most of the magic of a mod/con comes from modulation, so why can't we have some of that US Boiler G-series iron paired with a modulating (or even a two-stage) burner?

and there is the issue

@ May 14, 2013 11:29 AM in Cadet Combi boiler

if they can find a way to sell them for $500-600 more than an equivalent output CI boiler they will have a winner -- as long as they don't develop some form of midlife meltdown or require inordinate amounts of service in order not to.

Metric union pumps

@ May 13, 2013 10:54 PM in Cadet Combi boiler

What can we actually buy here in terms of small ECM union pumps?  Stratos Pico never made it as far as I know, and the true microcircs are even rarer.

thanks...