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3 Answers

New HVAC not blowing cold enough... what are the common causes?

I have just had a second new HVAC unit installed. A Trane xr17 condenser and s9v2 furnace. it is installed in my conditioned crawlspace, and I have an identical setup in my foam encapsulated attic.

Asked By John Sexton | Oct 18 16
7 Answers

Mitsubishi minisplit reconfiguration


Asked By Ben Thrush | Oct 17 16
4 Answers

Underfloor hydronic: foil faced insulation or aluminum diffuser plates?

Hello: I have a hydronic underfloor system (double pex-piping within floor joist space). The installer used NEITHER diffuser plates to hold the piping NOR reflective insulation. The performance has been disappointing and after having read many of your posts and Q&A I am convinced I should do one or the other at least. The insulation in the joist spaces is R11, kraft paper facing to the basement.

Asked By Trevor Laubenstein | Oct 14 16
8 Answers

How best to install HVAC return duct on outside of house?

Basic facts: 3 level house built on a down slope hillside lot in 1994. HVAC zone one covers main and upper floors. Zone two heats lower floor bedrooms. Equipment room located on lower floor. Climate zone 3c---SF Bay Area home. Large SW facing windows heat up main floor (family room) and upper floor master suite.

Asked By Joe Geesman | Oct 4 16
1 Answer

Room HRV

Just completed exterior renovation on a 200+ colonial. Removed everything from outside air sealed, installed roxul, plywood, taped joints, typar, 1 inch foam board, 3/4" strapping, vertical grain clapboards, etc... I have an ell that the radon level is now slightly elevated because it is so tight. It is basically 20 X 30 and attaches to the main house via a large opening. It has the kitchen and living room in it. It is a slab which I did not do so not sure how leaky it is. I want to install a single HRV and was looking at twinfresh comfo, Mica 60, Mica 150 style through wall units.

Asked By Terry Grube | Oct 17 16
3 Answers

When can we expect the R410a phaseout and what will replace it?

So this happened:

What's next? CO2 refrigerant? HFOs? How long before we see non-HFC refrigerant equipment on the market? I keep meaning to replace my gas furnace with a heat pump but now I'm thinking maybe I should wait…

Asked By Nate G | Oct 15 16
2 Answers

Are minisplit refrigerant lines better in a wall or outside?

Will the heating efficiency of a mini split operating in a cold climate be effected by whether the refrigerant lines are run inside the walls and kept warmer vs running them down a chase on the outside?


Asked By Michael Prisco | Oct 14 16
9 Answers

Best way to insulate for staple-up radiant heat?


Asked By Jack Roberts | Oct 13 16
3 Answers

Minisplit compressor

Hey all, I installed a Fujitsu compact cassette in summer and with the weather getting cold it has started to run its heating cycle. I've noticed that the outdoor compressor generates a large amount of water in heat mode. Specifically it is able to fill up a 5 gallon bucket in slightly more then a day. I know during extreme cold it can cause ice to form and then melt out the bottom. But is it normal to constantly have water coming out of the outdoor compressor even during mid 40s weather? Can't find anything in the manual.

Asked By Chris King | Oct 12 16
15 Answers

Retrofit HVAC installation in Zone 6a

Our house is a bungalow (1200 sqft) with a 600 sq ft split addition near Toronto, Canada ~ 6A. It is reasonably tight (spray foam throughout).

Our HVAC Retrofit will include replacing an old oil boiler with a NG appliance and installing a ventilation and AC system. When making decisions about this retrofit, IAQ is our most important criteria, followed by operating cost. My wife has a few health issues that make IAQ very important to us.

The two systems I am considering are:

Asked By Joe McRae | Oct 7 16
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