Best Of
Re: Carbon Monoxide Question
i give you a few rules that people forget again and again.
perfect combustion of HC ie a hydrocarbon (gas,oil,etc) produces
water and co2 and whatever non hydrocarbon junk was in the fuel like sulfur into sulfur-dioxide - and if it's hot enough, it also burns the oxygen and nitrogen in the air into nx or oxides of nitrogen,
now if the mixture is rich - ie not enough air (O2) to go around for all the hydrogens and carbons, then you get a little water and co (carbon-monoxide) a instead of co2 (carbon-dioxide) and if you really dont have enough air, you get "C" pure carbon (soot), and co, and hc (unburnt hydrocarbon)
if the mixture is to lean (too much air) you DONT, i repeat DONT get CO!!, but you do get lots of hc (unburnt fuel) and o2 (yes real unused oxygen in the exhaust, which in a car, the catalytic converter uses to burn the left over hc at a lower temperature)
so a deep blue flame may indicate the hottest mixture - but not necessarily no co, you need to cut the air down past the hottest point to the lean side to guarantee that no co is produced - indeed in cars the mixture is leaned so you dont get detonation when the spark goes off way before the piston reaches the top since the fuel and air particles are more spread out, the flame front travels more slowly from molecule to molecule until it's in full combustion at the top, i am a pilot of light piston aircraft and i always lean the engine until it's at least 50 degrees cooler than peak ie lean of peak which gives the engine the longest life, to go richer than that, you would have richen up the mixture until the exhaust temp reads 100 degree lower or rich of peak, in order to get the mixture rich enough to cool off the cylinders to a point, that offsets the heat created by the faster burning rich mixture, of course rich of peak is a huge waste since it produces co and less energy per gallon, as opposed to 50 degree lean of peak (ie lean until the engine is 50 degrees cooler than max) which give you a 99% complete burn, and a far softer flame front
this is another reason why it so important to use primary/secondary/closely spaced tee injection, since with a lean mixture, you really need the keep the boiler above 140 degrees so the you dont get a lean miss, ie heat+air+fuel not connecting!!!
it's mind boggling that, these simple sociometry rules are lost on many engineers, mechanics, and manufactures alike
Kal Row
Re: Viessmann cast iron boiler replacement.
John the CU3a can be piped like any old school boiler, if leaving the piping as is keeps costs down. It’s hard to imagine the owner paid large dough 30 years ago, and now wants to go on the cheap- give him the best!
It’s like pulling a G115 or an EK and installing a Smith or a Utica😀
humbly, the European boiler proponent
GW
Re: Plate heat exchanger
This falls into that category where you look at the BOM cost of the hydronic bits VS resistance floor heat and your ROI is measured in decades.
I would install some resistance mats on a nice thermostat that only runs the heat when you'll be using the bathroom and for freeze protection the rest of the time. The operating cost of this will be pretty small and none of the complications of dealing with frozen pipes or glycol.
Kaos
Re: Equalizer Return
The second part of your statement has been documented and debated here. Not sure that I understand the first part. That pipe that we call the equalizer, is also a drain pipe for the header.
Re: 1930's Hydronic System help understanding
The only thing you need to calculate is the water circuit with the highest resistance to flow. Building height means nothing. PSI means nothing. Find the circuit that has the most resistance at the flow it needs. That is the head the pump needs to overcome. Then use that head with the total flow you need for all circuits.
Re: Trouble getting an Air-to-water heat pump for radiant retrofit in Virginia
Second chart is COP vs outdoor temperature:
I'm going to throw a couple of asterisks in here. First, the Arctic only reports three numbers, one of them is 3.1 at 19F, which is the yellow ball. I think that's an error, looking at where the other yellow dots are. If you take that one out the yellow line would be pretty much in a line with the others.
Second, the Mitsubishi, blue line, is a vapor injection model and unlike the others it doesn't have a straight line, it's really two lines depending on whether VI is enabled. It typically kicks in around 20F, and COP suffers while capacity is retained.
Re: Difficulty in Properly Sizing Equipment - 2140 Sq Ft New Construction Spray Foam House
Thank you for your kind words and confidence in Energy Kinetics, @2Luckysat .
The stackable Frontier EK1 is an excellent choice based upon your description. Because your home is will be so tight, it may be under negative pressure; for that reason you may want to consider a sidewall vented version, which will also save the chimney costs. The vent fan is quiet and should last a long time, it does not add significant complexity as there is only on additional proving switch and the fan motor. Today's oilheat is ultra low sulfur fuel which means boiler scale buildup is virtually eliminated. Going in the natural draft chimney direction (at least 10' high), we recommend a 5" corrugated metal liner although a 6" liner would also be more than adequate.
I think that it makes sense to install a heat pump for anyone replacing or installing a new AC system. The hybrid solution with a boiler and high efficiency water heater affords great flexibility and peace of mind in a potentially uncertain energy future. I agree with your two zone approach as well. For some extremely tight homes (near the passive house standard for heat loss); I saw a presentation where PVC was connected through rooms with a bathroom fan to redistribute the heating/cooling effectively with a single heat pump; the key in all applications is to make sure that distribution is adequate make all rooms similarly comfortable.
For the heat loss calculation, your heating and AC pro should be able to provide the calculations. As you mentioned John Hachmann, I'm sure he can facilitate your request if needed.
Adding further detail for @DCContrarian , after 400 kWh consumption, the all electric rate drops by about $0.04/kWh for PSE&G Long Island (see this link). @Hot_water_fan , good comments regarding output - one of the best sources and analysis that takes into account many field performance studies of heat pumps can be found here. This demonstrates that high efficiency cold climate heat pumps operate at a COP from about 2.0 to 2.5 at 30°F, and efficiency drops further as temperatures fall (a COP of 2, or 200% efficiency would lower $0.25/kWh to $0.125 or about $5.00/gal of oil equivalent; this compares to oil at $3.50 per gallon at 85% efficiency or $4.11 equivalent - a lower cost to operate with added comfort and quietness of operation). This reinforces the hybrid solution for heating economy, comfort, and emissions reductions with an efficient boiler and biodiesel blends.
Best,
Roger
Roger
Re: Difficulty in Properly Sizing Equipment - 2140 Sq Ft New Construction Spray Foam House
What are your local utility costs? Around me oil is about 3x the operating cost of a heat pump so it makes no sense for a new build.
You area already adding ducting for AC, so your additional cost is only the up charge to a heat pump which will be a fraction of the cost of oil tank, boiler, plumbing and rads.
18/BTU per sqft in zone 4 sound very high for a tight new construction. I would doublecheck the manual J assumption as something is off. It should be closer to 8-12btu/sqft.
Even assuming 39k is correct you could heat the house with a combination of:
https://ashp.neep.org/#!/product/64682/7/25000/95/7500/0///0
and
https://ashp.neep.org/#!/product/64684/7/25000/95/7500/0///0
These are modulating units, if you look at the turndown on cooling it is pretty decent so even though it is oversized for cooling load, it should still turn down enough.
My guess once you get your manual J dialed in, a single 2 or 2.5 ton cold climate heat pump can heat and cool your place without issues.
Bonus of a heat pump is the SEER rating on it is much higher than your typical AC, so your cooling costs will also be significantly less.
Kaos
Re: correct gpm for open loop geothermal
Standard condenser water flow when you recycle the water is 3 gpm /ton nominal. Older ac systems that used city water and dumped it were based on 1.5 gpm/ton because the city water was colder.
So heat pump or not it doesn't change much your between the 1.5 and 3 gpm/ton. Don't forget 1 ton of cooling is 12,000 btus but you have the added heat of rejection from the compressor which is usually figured at 1.3 x 12000 btu or =15,600 btu/ton which used to be referred to as "tower tons" as a cooling tower was used.
Well water may be as cold as city water or it may not be. I seriously doubt the 1 gpm/ton the well guy said is correct
The manufacturer would be the best place to go to get specific information based on water temp and gpm flow. There will be some leeway on this