Joined on November 26, 2011
Last Post on April 24, 2014
@ April 7, 2014 9:38 AM in Value of converting oil/steam to modcon gas?in high density neighborhoods could certainly present challenges. What makes them truly infeasible?
@ April 7, 2014 9:30 AM in Anyone familiar with "Heat Load Pro" software?run it on Cocoon https://getcocoon.com/ runs hosted Windows stuff in the cloud.
Edit: No more of that, thank you. Thank the MS legal team.
@ April 7, 2014 9:21 AM in Install electric tankwould simplify it.
The "cold tank preheat" could actually reduce required winter rise a bit. Heck, you could run the heatpump just to get the water up to 60ºF and burn very little electricity.
@ April 6, 2014 10:48 PM in DIY Solar adviceThe lower the distribution water design temp for the system, the larger the solar fraction can be. The lower the specific energy consumption (BTUs per degree-day per square foot) the lower the cap cost for collectors and storage.
@ April 6, 2014 9:49 PM in Install electric tankI like the concept.
Now can we build it so an ordinary customer can live with it? The more I think about legionella the more I realize it's really a tough nut to crack.
@ April 6, 2014 11:32 AM in Central air vs mini split?I'd install radiant tubing in the ceilings (and perhaps a few bathroom walls) and a hydronic heat pump for both heating and cooling. Then a VRF small duct A/C system sized to handle latent loads and MUA.
@ April 6, 2014 11:23 AM in Install electric tankdeal with the stagnant water in the unused tank?
@ April 5, 2014 1:33 PM in Add-on fans for old convectorsI don't believe the Methodists intended this one to be uncomfortable, but they did build it in a era of stupid cheap natural gas, so the boiler would pretty much chug away at full bore from mid-November through early May.
A few years back they added a row of ceiling fans down the middle of the building to aid in destratifying the air. We're just trying to find a way speed up the recovery if we can.
I've got them starting on a radiation survey next week so we know what we have to work with. First pass indicates we may be able to replace the existing two natural draft boilers (Burnham Holiday firing at 480k and a Peerless 211-5) with a single 399k mod/con, or perhaps a pair of 250's.
@ April 5, 2014 1:19 PM in Add-on fans for old convectorssome good info there in any case, should we decide to fabricate them. We would control the speed via the DDC system to optimize comfort.
I've reached out to the Jaga folks to see if they will sell components.
@ April 5, 2014 12:03 PM in Indirect or Combo Boiler with Recirc DHT?allows the recirc to work without firing the tankless. The tankless takes over as soon as flow increases to the point where its sensor tells it to fire.
The bottom line is that tankless water hears are not the be-all and end-all that the salesmen want you to believe. They are fantastic at what they do, but for many customers a tank-type heater (especially an indirect) can actually be a better option. The extreme ∆T conditions experienced by their heat exchangers is a poor match with hard water, most especially if they are not regularly maintained. We recommend tankless when it makes sense and are big believers in them for the right application.
@ April 5, 2014 11:23 AM in Add-on fans for old convectorsin an old church. Convectors along the sidewalls of the sanctuary, which typically only needs heat on Sundays. Trying to bump up the recovery rate as we design the new boilers and controls.
I'm pretty sure I saw something with a row of ECM DC fans (like computer fans) that would fit in the case. If not, I know some guys who can probably fabricate them.
@ April 5, 2014 10:52 AM in Indirect or Combo Boiler with Recirc DHT?with the vast majority of tankless water heaters. That's why Heatpro adds the baby electric tank -- to keep the tankless from short-cycling as the recirc line cools.
What I was suggesting is a variation on the European model, where you install an electric tankless near each point of use. Our fuel costs are radically different here, especially with current NG prices. On a per BTU basis, electric resistance costs 6X what NG does here, but I still recommend it for specific applications. If the electric heat source only runs a few hours per month (filling a big tub) or even a few hours per year (backing up a solar DHW system) the reduced installation cost, maintenance, space requirements, and simplicity can easily trump that of a larger gas-fired heater. Properly sizing the primary system will save on first costs, fuel, maintenance, and space requirements. If a building has a remote bathroom or small kitchen in a guest house, an electric tankless can heat the water until hot water from the main heat source makes it down the line. It only runs for a minute or so each time the faucet is opened, and drops out of the circuit as soon as it is not needed.
@ April 4, 2014 10:39 PM in Indirect or Combo Boiler with Recirc DHT?If you have something like a soaker tub that gets used once a week, it may make sense to install an electric tankless as a dedicated booster just for that load.
@ April 4, 2014 10:26 PM in steam boiler maintenanceyou should drain a bit from the mud leg every so often. Maybe once or twice per season?
@ April 4, 2014 5:17 PM in Add-on fans for old convectorsRoughly 3 feet to five feet in length. They're recessed in the wall -- haven't pulled them apart yet, but I'd guess the fins might 4 inches or so.
@ April 4, 2014 4:34 PM in Add-on fans for old convectorsAnyone have a source for low-profile high efficiency fans that can be retrofitted to 1950's era wall convectors? I vaguely recall seeing something here awhile back, but perhaps it was on another site.
@ April 4, 2014 11:24 AM in Bad hydronic panel install...Working space
@ April 3, 2014 10:05 PM in Stinkbugsused to be common around here. Siberian Elms and Alianthus have beaten them pretty badly in most places.
@ April 3, 2014 10:25 AM in what is the maximuin water flow through 1 inch copper at 50 psiare different, and definitely part of the engineer's job. He can choose from a huge variety of heads, with a range of coverage patterns, flow rates and areas depending on pressure. Is this a 13R job? If not, you might consider what occupancies he is designing to and perhaps engaging the architect and/or the fire marshal to see if you can veer them off of 13, at least for the guest rooms. I've done it and saved a pile of money.
@ April 3, 2014 10:10 AM in Nest for the UKthat installing a programmable thermostat (no matter how smart) on a radiator system with TRVs will hardly make things better.
@ April 2, 2014 9:21 AM in Burnham gas conversionI've asked before for a reason this should not apply to boilers http://en.wikipedia.org/wiki/Magnuson%E2%80%93Moss_Warranty_Act
The way it was explained to me (when I worked in a different industry) was that in the event of a claim, the burden of proof fell on the manufacturer (they had to either prove that the aftermarket part actually caused the failure or honor the warranty.)
@ April 1, 2014 11:24 AM in Indirect or Combo Boiler with Recirc DHT?The 9U curve runs from about 9 feet to 12 GPM. It consumes about 40 Watts.
The ecocirc e3-4 curve runs from about 5.5 feet to 5 GPM. It consumes 2-10W at full speed -- even less if you buy the Vario version and turn it down.
The overwhelming majority of DHW recirc systems (both commercial and residential) we encounter are overpumped. This makes some sense with a demand system, since the pump is only powered for a short time and you need the water to get there fast. For continuous recirc or timed systems, it wastes a lot of both heat and electrical energy.
If the existing piping is copper, and especially if it increases to 3/4" as it nears the pump, you might consider reducing the size of accessible portions with PEX, perhaps even 3/8" from the individual branches. I'd also look at balancing valves for the branches. Don't forget lots of insulation.