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10 Answers

Options for garage heat

I would like opinions regarding options for heating a garage. I know, I know, "Why the H@!! are you heating a garage?" will come to mind for many of you. Others will agree that it saves on car repair costs, improves longevity, and allows for storage of "perishables" such as paint cans, bulk canned garden vegetables, and other things wife understandably does not want in house.

Here are the pertinent factors shaping the decision:
* Super-insulated house, Manual J heat load calc gives 12,400 BTU/h (3.6 kW) peak heating requirement (for garage alone)

Asked By Kent Jeffery | Nov 20 14
3 Answers

Vent separations and strategies

I'm building a home where I'm venting a high efficiency propane forced air furnace, a HRV (stale indoor/fresh outdoor), an on demand water heater, and a propane dryer from a mechanical room in about 8 feet of horizontal wall area. Additionally, I'm spot ventilating a range hood and bathroom fan on adjacent walls. My biggest concern is that I have dry fresh air for the HRV. There aren't any windows to really worry about and the mechanical room is on the first floor of a two story home so I can go up with some of the vents.

Asked By Jack Nichols | Nov 20 14
3 Answers

Mod-con forced hot water system that squeals

My plumber recently replaced the boiler in my small 3-zone Colonial with a Lochinvar WHN-85 boiler with a Lochinvar SIT 40 indirect water heater. Seems to work well, but I've been having trouble with noise.

First, the boiler occasionally emitted what I called a foghorn noise out of the exhaust pipe (the plumber opined it was a French horn). The solution was to tune the mixture to the rich side of the specified range (i.e. more gas per air, and more CO2 in the exhaust), which made it go away.

Asked By Daniel Griscom | Nov 19 14
1 Answer

Make up air for clothes dryer; exhaust only system

In new construction with an exhaust only ventilation system, is there a need for a make up air source for an electric clothes dryer. I am toying with the idea of some supplemental passive air sources...

Asked By Robert Holland | Nov 19 14
4 Answers

What do I do about my backdrafting oil-furnace?

Last weekend after noticing my bath fan wasn’t working. I went into my attic to see what was going on. I found the vinyl flex duct that was snaking across the attic floor full of water, so I swapped the fan for a high-quality model and did a nice job running 4-in. aluminum pipe to the outside. The fan is rated at 70 cfm and now my bath doesn’t fill with steam and my windows are no longer fogged up in the morning.

Asked By Patrick McCombe | Nov 19 14
8 Answers

Options for temporary heat in MN winter

I'm interested in the opinions of builders and others regarding temporary heat during contruction. My southern MN home is enclosed, windows in, and exterior walls spray foamed. Not as air tight as it will be, but pretty tight nevertheless.

Options include:
1. electric resistance space heat - pros: convenient, no fumes cons: most costly option per BTU, safety concerns for unattended heaters
2. portable kerosene heaters - pros: have unit available cons: fumes (about choked me when used last Saturday), need to refill reservoir tank every 36hr

Asked By Kent Jeffery | Nov 18 14
2 Answers

ERV - where does the moisture go?

I understand the difference betwen an HRV and an ERV - that the HRV transfers heat between the incoming and outgoing air while an ERV transfers both heat and moisture. I am puzzled as to how, in a house with an ERV, the moisture generated by bathrooms, laundry, people, dogs etc actually leaves the building if it is transferred to the incoming airflow ? Also, what stops odors being transferred between outgoing and incoming air ? I haven't mentioned cooking because I'm assuming a range hood with its own make-up air will be used.


Asked By Peter Hastings | Nov 18 14
0 Answers

Brands of HRV?

Anyone have any experience with either Lifebreath or Imperial HRVs? My architect specified Zehnder, but my HVAC guy has installed Lifebreath and Imperial, but not Zehnder.

Asked By stephen sheehy | Nov 17 14
5 Answers

Minisplits in the humid southeast?

I'm currently working on design for a house in the southeast, on the border between climate zones 3 and 4 (officially 4). Tight site, 700sf footprint, 3 floors over a walk out, unfinished but minimally conditioned basement.

Wall composition isn't settled yet, though the minimum is likely 2x6 studs with blown cellulose or open cell foam and 2" exterior xps. Basement is possibly thermomass if the numbers shake out OK. Given the small footprint and envelope, I'm hopeful that we can opt for decent walls, roof, and windows.

Asked By Chris B | Nov 17 14
5 Answers

What's the best wall height for a ductless mini split heat pump?

Hello out there,

Asked By Theresa Spear | Oct 26 14
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