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4 Answers

Minisplit design/Manual J question

Hello all,

I am working with an HVAC contractor to design and install a multisplit system for our 1950s ranch renovation. As an FYI, we've done a substantial amount of upgrades to improve the tightness and insulation of the home although at 60 years old the house still isn't perfect. I'm now hoping to replace our aging ducted air handler with a new ductless system. Motivation to go ductless is driven by many factors that I won't get into in this post (both efficiency and a more practical issue of headroom in our finished basement).

Asked By Brian Gray | Jul 31 14

4 Answers

Long room minisplit installation location?

11' X 30' room. Fujitsu 9rls2h. The specifications shows the flow pattern is long and skinny. Would it be best to install at the middle of the long wall or install at the end on a short wall? There will be ceiling fans at the midpoint and at the point farthest from the minisplit if on a short wall.

Asked By Shawn Shumaker | Jul 28 14

1 Answer

Ventilation to cool down poorly-insulated house

My wife and I recently bought an old (1880's) two-story duplex with separate apartments on each floor, each about 750 square feet and very poorly insulated. We have long-term renovation plans, but our primary near-term complaint is the inability of the apartments (especially upstairs) to cool down at night -- even with our quite cool summer nights here in Northern Colorado and all the windows open. We don't want air conditioning, but we would like to improve night-time ventilation.

Asked By Kevin Ummel | Jul 24 14

13 Answers

Replacing boiler and perhaps radiators in small Massachusetts colonial

I have a 2300 square foot colonial, built 1960 in Zone 5A, and I'm looking to replace the boiler with a direct-vent mod/con boiler, with indirect hot water. Goals would be increased efficiency (which isn't just about saving money), reliability, low maintenance, and retiring the current chimney flue.

Asked By Daniel Griscom | Jul 19 14

5 Answers

What if I have a too-small boiler installed?

You've seen my posts elsewhere on this forum: I'm shopping for a new gas FHW furnace with indirect domestic for my 2200 square foot Massachusetts colonial. I want a good, efficient, direct vent furnace. My gas use suggests that I don't need more than 28kBTU/hour on the coldest winter days, so my current 95kBTU/hour output boiler is three times what I need. Almost everything I've read here and elsewhere agrees with this.

Asked By Daniel Griscom | Jul 20 14

41 Answers

Dare to DIY a mini split install?

Hi all,
Can editors step out from behind the curtain to ask opinions, too? I'm planning to redo my garage shop this Fall and although my primary heat for the space is a woodstove, I'd love to have some supplemental heating, and cooling in the summer would be great, too. I'm no schlep when it comes to remodeling work, but have never installed or seen a mini split install. Would I be a fool to try the install myself or have the kits gotten streamlined to the point that its basically plug and play, complete with factory-charged units and quick connect line sets, etc?

Asked By Justin Fink | Aug 22 13

1 Answer

Fixing undersized ductwork - best approach for difficult section?

I've just uncovered some ductwork in my house that needs to be addressed. It is a 1400 square foot two storey brick house, no wall insulation, in climate zone 5. It's a narrow and tall Victorian house and the ductwork in question feeds the rear of the house on both storeys - kitchen on the first floor and a bedroom on the second. These rooms have been poorly heated ever since I've lived here but last winter, which was particularly testing, the rear bedroom was basically uninhabitable without backup electric heat.

Asked By Jonathan Dalton | Jul 10 14

4 Answers

ERVs and formaldehyde

In the Allison Bailes interview with Dr. Iain Walker http://www.greenbuildingadvisor.com/blogs/dept/building-science/intervie...
the emerging concerns about formaldehyde transfer (or non-transfer) are discussed at the end. As stated in the interview, it's hard for the purchaser to know the exact extent of the issue with particular units, but Dr. Walker does describe the 2 methods of exchanging moisture, wheel and membrane with the latter being preferred.

Asked By Greg Wilson | Jul 8 14

2 Answers

Minisplit efficiency - multiple single zone vs single multi-zone

Hello all,

Asked By Brian Gray | Jul 2 14

1 Answer

Deciding between conventional heat pump and minisplits

I'm working with homeowners who are considering an HVAC upgrade for their new house, approximately 2,000 sq.ft. It's vintage 1970's, but we'll be doing a number of air-sealing and insulation upgrades. Eventually we'll have an HVAC design professional come check the place out, and make recommendations, but for the moment we're considering what options are out there. Currently, the house has the original forced air ductwork, with a new heat pump put in last year by previous owner. It's a Lennox XP14-042, with matching new air handler and resistance heat.

Asked By Andy Chappell-Dick | Jul 8 14

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