Community: Mechanicals

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50 Answers

Solar thermal systems for heating water

Jin this is for you and Richard

Let's run the costs and the systems through the paces

so far I hear $16,000 for a Caleffi system and maybe that for labor? $32,000
saves $500 a year

CO2 production unknown to manufacture
Very little CO2 to run the ECM circulators

There are much less costly systems

NYSERDA here in NY is unveiling a new program this January
Will post more about it when they tell us more

Jin, Richard, others... what say you all

Asked By aj builder, Upstate NY Zone 6a | Dec 15 14
87 Answers

Modern (hydronic) heating and what all should start to know as of 2014

I stumbled upon this site to do with researching an update to a (hydronic) heating system I installed two decades ago.

So much has changed mainly the best change is the access we all have now to information.

This is the best read I have had off the internet to do with modern current (hydronic) heating.

Dana, besides your wealth of help here, this pictorial is great for the visual types like me.

http://www.duluthenergydesign.com/Content/Documents/GeneralInfo/Presenta...

Asked By aj builder, Upstate NY Zone 6a | Dec 4 14
17 Answers

Is this furnace venting/leaking problem as bad as it looks?

I'm visiting my parents' place for the holidays and using my newfound amateur knowledge of building science to find everything wrong with their old house. :) I'd like to get some confirmation on the most worrying thing I've found: a leaking furnace flue.

The furnace is a 30 year old 80% efficient model in the basement with a round metal flue that goes into a masonry chimney and exits about 40 feet higher at the top of the chimney. The connection to the furnace in the basement curves down at one point:

https://i.imgur.com/xBMUIUo.jpg

Asked By Nathaniel G | Dec 20 14
5 Answers

Ventilating

I own a 1100 square foot vintage condo that desperately needs ventilation but has no duct work no HVAC no dehumidifier, the space gets stuffy and hot, very uncomfortable in the summer and in the winter with everything closed, condensation develops on the windows.

Would appreciate any advice with what the best way to ventilate the space is without breaking the bank: an air handler? The Broan ventilators?

Thanks!

Asked By Vishy S | Dec 21 14
3 Answers

Mechanical room size

I'm looking at designs for slab on grade, 3 BR, 2 Bath houses under 1500 sq feet (heat provided by heat pump/baseboard heaters). Can anyone share their experience with how large the mechanical room should be? Hot Water Tank, solar power inverter, HRV, Networking/cabling, Power Panel, main water cutoff are what I see as the main components. Is there anything else that should be planned for? I don't have the option of moving these items out to the garage (eastern Canada), and many house plans I've looked at assume there is a basement or just have small areas carved out for H/W or HRV.

Asked By Corey B | Dec 20 14
15 Answers

Unfinished basement, Cgi 5 gas boiler, Z vent. The outside air is making the basement cold. Can it be louvered?

Hi all,

So Ive just finished sealing the rim joist with 2" XPS (Dow Blue board) and spray foam, sealed the perimeter between the walls and floor with silicone, installed a air tight sump lid but was still getting drafts.

So Ive tracked it back to the Z vent for our CGi5 boiler, it seems the air is coming in through the z vent and back that way. It has the Z Vent termination cap on outside but was wondering if it could use a metal louver on the outside so when the boiler isnt firing it the drafts stay outside?

Asked By Darren Finch | Dec 16 14
38 Answers

Heating with modulating condensing units

So far my looking into the use of a modulating condensing unit has left me with
the following;

They are high tech
They cost more than some older tech
They need good water with proper hardness and PH
They need a tech that is trained to maintain them
They do not condense if the return water is above 125 degrees.
Many install set ups include primary, secondary and what I call tertiary loops which to me add cost.

I can't understand how we go from $1000 to heat water to $8000 for all the parts for a fairly basic

Asked By aj builder, Upstate NY Zone 6a | Dec 15 14
7 Answers

Flow control valves for radiant floor heating

I have high efficiency house in central Vermont. It has radiant tubing in the floor for heat. I am trying to get the on demand hot water heater, a Takagi, and the circulator pumps to run as little as possible. Electricity is the biggest obstacle. The house is off grid with PV and batteries. Both are a little on the small side. The house has 6 zones with flow valves on each. No zone is over 400 feet. Tubing is 1/2 inch PEX. Current Delta T when three or more zones are open is 10 degrees. I currently have all flow valves wide open.

Asked By Jon Olson | Dec 16 14
9 Answers

What about installing a cooktop downdraft vent/ducting in a slab?

I have installed two cook top downdraft vent/ducting systems with great success but never in a slab. In this case the duct would be embedded in the concrete slab with exterior grill through the perimeter foundation and still above grade. What should I look out for, take into consideration?

There will also be a return from an HVR system in the Kitchen area. (Thanks to the excellent article by Martin I am in dialog with Zehnder)

Asked By Caroline Di Diego | Dec 14 14
8 Answers

Will my generator run a minisplit safely?

My new house will be heated with two minisplit heat pumps. Here in Maine, we have lots of power outages, so we're also putting in a whole house standby generator.

I've been informed by the Fujitsu installer that we should not plan to run the minisplits off the generator when the grid power goes out. We also may install a heat pump water heater and maybe even a heat pump dryer. We'll have some backup heat.

I have two questions:

1. Would the generator power damage the heat pumps or prevent them from operating?

Asked By stephen sheehy | Dec 13 14
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