"Mechanicals" New House, Old Soul - Ep. 10
Вставка
- Опубліковано 22 сер 2023
- The history of air and water heating and cooling in America. How did its integration within a home shape how building was done in Texas, and elsewhere? How does the need for plumbing and ventilation influence a building’s design? Brent will look at different ways mechanical systems are integrated, with the best ones being present and effective -- but not very visible.
Learn more about The Unico System here: landing.unicosystem.com/new-h...
Stay up to date with The Unico System on social media: / theunicosystem
Next Episode: September 6th, 2023
Craftsmen Go with Sashco! Try out Sashco’s line of sealants with this exclusive sampling offer extended to our Pro viewers. Request your sample kit at www.sashco.com/build-show/
Subscribe and follow my Podcast on Apple or Spotify!
Apple: apple.co/32AOwgU
Spotify: spoti.fi/3FXNg4X
Sign up for our twice-weekly newsletter:
buildshownetwork.com/newsletter
To sponsor a video or advertise with us visit:
www.buildproductions.com
Want to learn more about building? thebuildshow.com/
The Build Show on Instagram: / thebuildshow
Huge thanks to our Show sponsors Builders FirstSource, Polyguard, Huber, Rockwool & Viewrail for helping to make these videos possible! These are all trusted companies that Matt has worked with for years and trusts their products in the homes he builds. We would highly encourage you to check out their websites for more info.
www.bldr.com/
polyguard.com/
www.Huberwood.com
www.Viewrail.com
www.Rockwool.com
Sync ID's:
MB01GQVBPGLU3PN
MB01FKGXWGEEGSN
MB01PZJSC2MPSCR
MB0136KLFXJXAIH
MB01PE2CQO7B7GV
MB01QAOUH3NGCMP
wouldn't it be cool to design a mini split that fit into a chimney and looks like a fireplace screen or is hidden above the opening with a feaux log blower
Diakin is now going to patent that idea and sell them for 10,000 a piece 😂😂
Unico is a great solution in many applications. Good presentation.
Your advice is spot on with regards to cooling. I have restored old homes as a hobby since 1972 and have always been challanged to not wreck the details of the home to add HVAC to a 1930's - 1970's house. Wheather it was a traditional horitionzal air handler, fan coil, or chiller driven air handler I always put extra effort into condensate water safety back-up. In South Fl we're required to install a seperate drip pan and I always added a water sensor alarm to the drip pan that would alert when moister was detected so that A/C service could be preformed before drip pan became over filled and water damage resulted (Many A/C evaporators have a secondary high water drain which can also be used to trigger an alarm). I too would go to great lengths to use attics and crawlways this usually is more costly and time consuming but the end results are well worth the effort and expense to advoid the easy way of using an existing linen or clothes closet for the air handler/s. Ray Stormont
I'm using that small Unico ductwork to retrofit a cathedral ceiling. The ducts will fit up above the collar ties.
Such good advice. So many things to balance.
Curious, why/how are the chiller systems more efficient than a typical system?
1 - Main Benefit) Distribution efficiency Water has a much higher specific heat capacity than air (x3400 greater) and isn't a major parasitic load on the compressor at large distances like refrigerant in a VRF system. For example, losses at 500 feet for a VRF system is roughly 30% of the compressor power, whereas hydronic systems use a fraction of that power for their circulator. Modern ECM circulators can use about 10-20 watts for the average house in a well designed system. Check out Grundfos Alpha2 for an example.
Pro 2) Hydronic systems using radiant cooling can have a much lower water temperature due to their giant surface area (84F for heating or 66F for cooling are common in modern radiant systems using radiant ceilings or slab cooling). The max efficiency of a heat pump is dependent on the difference in temperature between the source (air or ground) and supply. Note this only handles sensible, not latent demand. Some chillers can use an economizer cycle that can cool at night, and this cools using just the fan and circulator and does not introduce night time moisture, like and air based system would. In cold climates heat pumps maintain much more of their output using a lower supply temperature, so this is helpful in Canada/northern US.
Pro 3) The thermal mass of water also leads to longer cycles times and better efficiency and reduced wear, especially with a buffer tank. Generally properly sized equipment is important, there is more leeway with hydronics.
Pro 4) Hydronic systems can target only sensible loads by keeping their water temperate above the dewpoint, and a separate system can handle latent cooling (like a dehumidifier or split dehumidifier). Humidity equalizes much more easily in a house than temperature, so ducting to every room is less important for latent only systems if door undercuts or jump ducts are present and the ducts can be much smaller. Using a system designed for each can avoid overcooling to deal with moisture (Florida, or Eastern US/Canada summers) or over dehumidifying to bring down temperature (desert areas).
Major Efficiency Con) Heat exchangers are what kills the efficiency of these systems. A water-water exchanger, common when using monobloc heat pumps in cold climates, can lose 10F. Going air-refrigerant-water in the heat pump and then water-air using a fan coil or hydronic air handler is not particularly efficient, but they can handle latent demand. However, comparatively, Matt often says that mini split heat pumps are not great at latent cooling (humidity removal).
Cold climates often mean using propylene glycol throughout the system (lower specific heat capacity and added cost) or using a water-water heat exchanger to isolate the indoor and outdoor loops (efficiency loss). New anti freeze valves (Caleffi iStop is one) could let you run pure water even outdoors, reducing cost and improving efficiency, but manufacturer warranty often demands glycol in the outdoor unit.
------
WHERE DOES HYDRONICS MAKE SENSE?
-------
Retrofitting large buildings where mini splits to each room is not an option. 3/4" insulated PEX (1-1/2" total) running to a fan coil is much easier to route. If fan coils are too ugly something like the Unico system Brent mentions makes sense. Retrofitting radiant ceilings is often an option too (adds maybe 2").
Note the scaling depending on the size of the building and heating vs cooling and latent vs sensible demands. It is inefficient in large mansions to have a mini split head or ducts in each room, since there is large interior areas that would require long ducts or refrigerant lines. Similarly the larger a building gets the internal heat load often increases, requiring more sensible vs latent cooling. These favour hydronics.
For an average sized, new construction, residence in hot and humid climates, like Florida or Texas, this makes little sense. There is heavy latent demand that hydronics does not offer the same benefits for.
Desert climates can benefit massively, since the dry air means latent cooling is often not needed or unwanted and radiant cooling can do a great job of efficient sensible cooling. Pre-chilling a slab overnight using cheaper electricity (if you have time of use pricing) or cool night time air on an economizer cycle can be beneficial.
Cold, but not arctic climates like northern continental or most of Canada can benefit from this tech. Modern heat pumps can also heat domestic hot water using an indirect tank. The all in one heat pump water heaters you often see on this channel or elsewhere are great for hot climates, but in the north when you're heating 8 months of the year it makes no sense to use the heat you just paid for from indoors to heat your water. The larger surface area means more efficient operation for heating. These areas often have lower dewpoints than the deep south.
@@rashton7990 holy cow, I feel like I just got an education. Thank you so much!!
You're very welcome! If you want more, I recommend the book "Modern Hydronic Heating And Cooling" by John Siegenthaler@@nyalsewell
@@nyalsewellthey aren't more efficient than modern VRF systems, primarily because your have to transfer heat twice rather than once. The extra cost of refrigerant leak detection is why you generally are hot/cold water in commercial. Also restrictions on refrigerant for global warming reasons is pushing people towards chillers.
These old houses probably had the chillers installed a while ago when their options were more limited.
@@Zorlig " _Also restrictions on refrigerant for global warming _ "
Fortunately, the hoax is being debunked by the day. No such thing as global warming, no such thing as refrigerant and ozone layers, and no such thing as "carbon is bad".
Really enjoy learning from you.
Okay ... here's your recipe, Brent. It'll work on any house, new or old. What? Yeah.
1) *Do not fight the stack effect* . This is why we like double-hung windows in Spring/Summer, yes??
Which means: Keep "central" (ducted, etc) A/C but put registers up high _regardless of floor_ . Having your feet cold in summer is unnecessary, so never use floor registers again. Why am I wearing socks in August? Because of the floor registers freezing my feet.
2) FORGET ducted heat, regardless of climate zone. Just ... don't bother. *Advocate and build the infrastructure and talent* that supports radiators. Or go with radiant heat floors. There's your hidden heat. Either way, let the heat rise in Winter, it is utterly amazing I don't care where your house is located.
Forced-air heat ultimately sucks for comfort, and it's ONLY become historically popular because of A/C, where everyone thought it was "smart" to only need one duct system. It's not smart, it's cheap, and it shows.
Couldn’t have said it better myself.
Hmmm, big problem with radiant is the latency. I turn my heat OFF when I leave the house for 30 min or more and turn it down to 60f when I sleep. Forced air warms up the house in minutes, so I save a ton of money. I'm in climate zone 7. Cant do that with radiant.
@@fox156 Requires proper insulation, then you can keep the temperature constant all day in each room.
Well, pretty rare and difficult to have more than R22 6" insulated walls. Not everyone can afford to live on a new custom house or put 2" of foam on the outside. In any case you're still spending "more" to heat if it takes hours to change the temperature 10 degrees and you can't turn the heat off when you leave for a few hours or sleep.
@@fox156 Very curious here. I live and work in zone 6. I don’t know a single person who turns their heat off for any period of time in the dead of winter. How is it possible that you can do it living in zone 7? Maybe I’m misunderstanding you. But it seems impossible to do, and a problem waiting to happen.
Beautiful brick house
How do they manage the air flow noise with a high velocity system like the Unico?
@ 6:50 those tall pillars are they stone or fiberglass? Do they have an I beam in the middle?
I think we should do more with chillers and radiant heat and cooling but it’s very hard to help consumers understand the value
An air-cooled chiller system is not necessarily more efficient than a split system. Typically, air-cooled chilled water systems are less efficient than split systems because you have the heat going from the space to the air to the chilled water and then to the refrigerant -- it is an extra step compared to split systems and you need energy to pump the water.
Exactly! Heat exchangers reduce the efficiency of systems
A chiller system is not more efficient than a split system. That doesn't make sense from just a pure physics perspective. The coolant is much better at moving thermal energy than water. It also takes far less volume to move the energy, and given that the pipes are smaller you have far less opportunity for heat to leak into the plumping (or out for a boiler system).
Do you mean refrigerant instead of coolant? An example of coolant is propylene glycol. Glycol-water mixtures have a lower specific heat capacity than pure water.
@rashton7990 indeed, I meant refrigerant. Thanks for pointing that out 👍🏻
Less than 4 minutes into the video, and for the life of me I just cannot find any BALANCE to be had...
couldn't watch this the music and noise was just too annoying.
High velocity system shilling, meh.