Community: Mechanicals

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25 Answers

Direct vent vs. power vent gas water heaters

A recent blower door test/audit has alerted me to the fact that my natural draft hot water heater can backdraft in worse case scenarios (range hood/clothes dryer/bath fan on). It seems to reverse back to a correct draft after a few minutes. It's only about 6 yrs old, so I hate to replace it, but not as much as I hate the idea of the back draft.

Asked By Erik Addy | Mar 8 16
32 Answers

Electric baseboard — mounting questions

I am converting to electric "baseboard" heaters in preparation for a solar install in a year. I live in a cold winter climate, Detroit. Conventional practice is to mount them low, preferably under a window.

However, mini-splits are mounted high. Here, ceiling fans are uncommon, especially with reverse cycle winter use. All of my rooms will have fans. I want to mount them high. This seems to make sense, given the fan and mini-split efficacy.

Asked By Marlena Crows | Jun 18 16
11 Answers

Mini split advice

Climate Zone 5, Oakland County Michigan, building starting in July
2357 sq ft ranch, 2357 sq ft walkout basement.
2x6 walls dense pack cellulose, 3 inches exterior mineral wool
R60 ceiling insulation
Superior wall foundation for backfilled walls
R 7 Windows from Klearwall
Have access to natural gas but prefer to go electric if possible.

Thought I'd try and get your thoughts Dana and others on our Heating and Cooling plan. We just had a Manual J calculation done:

Total heating required including ventilation air: 37,561 Btuh

Asked By Brian W | Jun 22 16
12 Answers

Does anyone have experience with Zehnder ComfoFlex?

We are building a new house and in the final stages of design. The design includes an HRV and Zehnder ComfoTube looked great until I discovered that it is not UL listed. So, I'm curious if anyone can provide feedback on ComfoFlex. There isn't much on the intertubes...

Asked By Trevor Fontaine | Feb 9 16
2 Answers

How to seal gaps around air conditioner lines?

I'm trying to install a Mini-Split Air Conditioner and looking for suggestions on how to seal the gaps around the lines.

At the place where the lines come through the hole in the wall, there're small gaps between the sleeve and the lines/pipe. I know most contractors don't seal them. But if I really want to seal them, what material should I use here?

Another place I want to seal is the end of duct hide where the lines coming out, I want to seal the opening to keep out small animals/insects.

Thanks ahead!

-Tom

Asked By Tom M | Jun 20 16
8 Answers

Ductwork in Exterior Wall

I know, don't do it. Here is my problem. I am renovating my daughter's house. She wanted a bearing wall removed and I knew that two supply ducts would be an issue. They are 6" ducts running from the basement to two second floor bedrooms. Furnace is near the center (front to rear) of the basement at the end of the basement. Bedrooms are above this end of the house.

Asked By Mark Reinmiller | Jun 15 16
4 Answers

Affordable Air-to-Water Heat Pump for climate zone 6B, Colorado

I'm looking for an air-to-water heat pump that I could use with a low temperature hydronic distribution system for space heating. I would also like to use the heat pump as the preheat for domestic hot water.

The mini-split air-to-air heat pumps are pretty ideal in many climate zones in the USA. On the western slope of the Rockies in Colorado, air conditioning isn't usually necessary. So I'd prefer one heat pump to provide space heating and much of DHW.

Asked By Pat Kiernan | Jun 14 16
8 Answers

Minisplit controls?

I'm planning a ducted minisplit system for our renovated large house.
It will be 4 floors (inc basement and cathedral attic) but likely 6+ zones given the size of the house (6k above grade).
Im looking at mitsubishi hyperheat or the fujitsu ducted sustems.

Q. Is there a major difference in the contrils in terms of features / quality?
Q. How do these work in a whole-house heat/cool use? I have wall mounted units currently but the have IR remote controls. What about zoning a whole house?

Asked By Edward Cambridge | Jun 13 16
10 Answers

Can one use a slab-over-slab radiant heat system?

Thank you all that answer my question.
Here is my question in short form:
Pole barn that was built as a small factory to be revamped to a new business and add radiant heat?

Can one add the heat system on the current slab and re-pour a new slab on top, where height and doors are not a issue? or Should one cut out the old slab add needed equipment and re pour a new slab. Again or Could new construction be a better option? Time and cost factors are important.
As a added note this is in mid northern Minnesota.
If you need more just ask. Thank you again!

Asked By Ken Jackson | Jun 10 16
10 Answers

Venting for kitchen, bath, electric clothes dryer — duct paths?

The bath and laundry are on the second floor. The master bath can go to the rear exterior wall. What about the other bath? Would a vent hood look out of place on the long side (front) of the house? Siding will be white Hardie lap siding.

Or would you run it through the framing to the back exterior wall (20 ft.)?

How about the clothes dryer?

How about the kitchen? Better to go straight up through the metal roof or to the exterior wall?

Would the vent around the white siding be a issue?

Thanks so much for this site.

Asked By Quinton Bryant | Jun 3 16
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