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14 Answers

Outdoor mini split condenser unit in an insulated ventilated box indoors?

I need to cool (summer) and heat (winter) one room which is total 16.7 x 12.2 x 8.5 feet (1731 cubicfeet) (5.10m x 3.70m x 2.6m). I would need a unit between 2 or 3 tons.

Unfortunately I am not able to install the outside condenser unit outside of the building. That is the reason why I need expert advice.

Asked By purpleAnt | Mar 20 18
3 Answers

Water heater power consumption monitoring.

I searched but only found one thread from three years ago. The advice then was to use a standard power meter. While the idea is good, the box and meter would take up a large amount of space and wouldn't really give much information about when the power is being used. Does anyone know of a reasonably priced option to monitor a single 240v circuit? Thanks

Asked By Calum Wilde | Mar 22 18
3 Answers

Mini Split in 1905 All Brick Home

I’m looking for a bit of help selecting a mini split setup for my historic district 1905 all brick 2 family home. This will be part of a major major gut of part of 2nd floor, so a number of energy improvements are on the docket. We will rent one of the units.

I would like to do ducted mini splits for each unit for aesthetic/historical reasons. I have heat pump water heaters already. This would be the only heat source, so heating loads dominate. Possibly 1 unit for front of each unit, 1 for back.

Asked By twoodson | Mar 22 18
10 Answers

ERV with HEPA filtration options

Hi Everyone,

Been a lurker here and I have a question and looking for advice.

Im building a new home, my previous home burned down. Im in Southern California, climate zone 3b, and my house will be pretty air tight, built with sip panels and using mini splits for heating and cooling. House is around 4300 sqft, I talked with some people and they recommended 3 Panasonic FV-04VE1 ERV units for ventilation throughout because of the lack of attic spaces and expenses.

Asked By m4tr1x | Mar 20 18
5 Answers

Mini Split selection

I know this has been a well documented discussion on here. Yet here I am continuing it. I am close to making the final mini split unit selections for my house. I'm looking for advice on comparing three specific models. Let me know if I should be looking at others?

As background information, I am in Chicago and will be using two 1-Ton units to heat/cool my house + wood burning stove. House will have R 33 walls and R 50 roof. 2,100sf two story.

Asked By Seth Holmen | Mar 19 18
2 Answers

Quietest heat-pump water heaters?

Hey There Fellow Tradespeople,

Wondering if anyone has any recent experience in shopping for heat-pump water heaters. Would love to know what some of the quietest models and makes are. I've Googled around and stumbled onto several outdated sources on this. Any thoughts out there? Thanks!

Asked By Dylan Kinsey | Mar 8 18
9 Answers

DWHR and HPWH vs Electric, Total Efficiency?

So it's well known that a Heat Pump Water Heater (HPWH) is far more efficient at heating water than a standard electric water heater, but what happens when we look at the entire system top to bottom, including Drain Water Heat Recovery (DWHR) as well as the building's main heat source?

Asked By Lance Peters | Mar 15 18
8 Answers

Heat-pump water heater: Air volume, etc.


Lots of good information here about Heat Pump Hot Water Heaters, thanks! My situation is unique, so I thought I'd get some feedback before I pull the trigger and purchase 2 Stiebel Eltron 80-gallon units to install in place of 4 40-gal resistance hot water heaters servicing 4 2-BR units in a multifamily building.

Asked By Tobeywan | Mar 13 18
7 Answers

Using supplemental heat pump hot water heater as AC+"battery" during summer

Hello Lakesideca Advisor,

I have a situation in my home where the (gas) hot water heater is on the 2nd floor in an area that is roasting (80F+) for six months of the year. In fact, the 2nd floor hot water heater is in the laundry room adjacent to two bedrooms that also tend to overheat.

I am intrigued with the idea of using a heat pump water heater as an AC unit with a "battery" (the tank) that heats during the day and which I can heat exchange with my (true) hot water heater for showers in the evening/morning.

Asked By CJ_Los_Alamos | Mar 14 18
45 Answers

ERV choice

So looking at ERV for my build, and comparing models. Want something efficient, but not crazy $$$.

The house hopefully will be tight and well it is on the larger side.
Main floor is 2275sq' walk-out basement is 1880sq' of finished area. (including unfinished area it is 2275 also)
So 4155sq' of living area, currently only 2 people and 2 large dogs.
Will have it's own dedicated duct work (heating/ac hopefully will be mini-splits)

Zone 6 (20 miles SW of Peterborough,ON)

I've looked at the following models

Asked By Dave B | Mar 12 18
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