Sorry about having to start a new string....for some reason, I can't reply
to anything this morning. Oh, well....
First off, Al. I appreciate your opinion. However, I highly doubt my 63
year old retired school teacher neighbor of 11 years would want to "pull my
leg", especially given the fact that he told me about all of this 3 or 4
years ago and I dismissed all of it as hogwash. He got his advice from a
retired Chemical Engineer friend of his who has taken up HVAC advice/studies
in old houses as a hobby. In fact, he showed me the study he did (the
retired engineer) that showed where he tracked the BTU's he was getting from
Citizen's Gas here in Indy (if he had to, how he rigged it up to monitor it
I have no idea). Anyway, basically he nailed Citizen's with the Utility
Board of Indiana for not supplying the same or adequate BTU's when the temps
got below 10 degrees. Seems they were cutting in some Coke gas (or
something akin, I'm not sure I remember) , which is not as good as pure Ng.
That is all fine and dandy, but they weren't telling anyone about it and
then they turned around and charged people as if they'd supplied only pure
Ng, when the impure supply was causing people to use more gas to generate
the same BTU's. No, that all doesn't mean squat. However, I think they're
trustworthy. I have an excellent BS meter and it doesn't tick when they're
talking. I highly doubt a 75 year old retiree (the ChemE) would get his
kicks by "getting over" on a 42 year old stranger, and I've seen his house
firsthand. Also, regarding the bill/check, Citizen's policy is any amount
overbilled over the amount of $100 is refunded in a check to the client.
Now on to some followup.....
Thanks, HeatMan, for your time on this...
Some other points/follow-ups:
1.) There is already visqueen laid down on the crawl space floor. It's not
sealed to the walls, but it comes to within at least 6 inches of the walls.
Is that good enough re the moisture/mold? Since the visqueen is already
down, and assuming I lay in the insulation on the walls and out on the floor
of the crawl space 2 ft out from the wall, do I still need "thermostatic
vents"? How much are they approximately? If the insulation is down, and
the visqueen is also, does the natural heat from the earth (55 degrees, no?)
still heat up the air in the crawl space in the winter and cool it down in
summer? I assume it work for us either way, no?
2.) Regarding the hole in the floor. Hopefully this helps with #3 below.
What I'm talking about is, in a location somewhere near the middle of the
house, cutting in a 9"x14" hole in the floor that would expose the crawl
space (obviously I'd put some sort of grate/grill on it). Then, to promote
circulation, running the bath fan 24/7, creating a flow from the outside
into the crawl space through the one unplugged crawl space vent, to the hole
cut in the floor, to the bath fan and up and out. That would also seem to
mitigate the moisture/mold potential in the crawl space, even though we have
the visqueen down already. If you reccommend not cutting the hole, is it
still ok to plug up the crawl space vents since there is visqueen down, or
should I still install the thermostatic vents? If so, how many, one for the
entire crawl space or one for each of the 6 vents tot he crawlspace from the
3.) Regarding #4 below and the venting of the boiler: I checked the unit and
its a Weil McClain, kind of hard to read the stamped plate with the specs on
it, but it looks like model number on the boiler is "PCG-5", "Series 3". It
says it has an A.G.A. rating of 114,000 BTU's per hour input and 112,000
BTU's output per hour. On visual inspection, there only seems to be the one
exhaust vent going straight up and out in its own flue separate from the
fireplace. No incoming air supply from what I can tell. Would the standard
aluminum tube (I believe it to be either 4 or 5 inches in diameter),
connected to the garage window and outflowing to the floor be good
enough/beneficial? It would seem that the cold air from outside in the
winter would naturally want to flow down through the tube (garage is
somewhat heated with a baseboard unit of its own out there, plus the garage
is on a slab, heating it a little). If it doesn't have an air source, what
has it been using before now?...just relying on the basically unsealed
spaces between the garage door and the frame?
4.) What does that BTU rating above equate to ? The 1,000 BTU's you
5.) What's a sealed combustion unit? Benefits? How much? Is that a
totally new unit/system? I was told to replace the unit we have now would
be about $5-10,000. ....or, simply buy the heat blower attachment for the AC
unit in the attic for about $800. Is that as efficient/desireable as the
6.) On the water temp in the system: I already turned this down from 180 to
140. That should be ok, no? Regarding the Outdoor reset, what is that? An
attachment? or should it already be on the unit? How much is it if not?
7.) Regarding the water heater: Its a Kenmore "Power Miser 5", at least
10-12 years old, in the garage next to the boiler. I do not have it
wrapped...should I? What provisions do I need to make for the vertical
pipes on the outside of it? Wrap those in it to, or tuck it inside of those?
On the temp dial, there is not a degree. Instead, on one end of the dial is
"Very Hot" and the other end is "Hot", with letters going from "Very Hot",
then "C", "B", "A" and then "Hot". It was on "B", and I turned it down to
"A", one level above "Hot". Got a guess as to where that puts it, degree
Thanks for all your time on this. I am currently unemployed and have been
for about 4 months now, so any dollars I can save to avoid $300/month gas
bills this winter is GREATLY appreciated! It sounds like the crawl space
insulation is a no-brainer. Am I OK with the R-13?
----- Original Message -----
Sent: Sunday, November 13, 2005 6:52 PM
Subject: Re: HVAC questions...
There was a city utility north of me that was caught pumping in compressed
air to the NG system when it got cold here(long time ago). That gas service
wasn't owned by the city after that...
Not around here. Besides, that's not an overbilled amount.
YMMV on the visqueen. I had mine to the wall in my old house. I used clear
and you could really see the water under it. Not putting it to the wall is
like leaving your car windows slightly open all the time.
If you lay insulation directly on the visqueen in the crawl, it's going to
become a soggy mess in a few years or less. I have no idea how much the
vents are, go to the box stores and find out! All insulation on the floor
of the crawl will do is keep that heat/cool in the dirt. I'd insulate
between the floor joists. Just make sure your home is rodent proof.
I wouldn't do it. Period.
Would it be beneficial? No clue. It probably would help, but you need a
certain amount of square inches regardless. Up until now, I'm fairly
confident the make-up air has been getting in somewhere...
You figure the combustion air requirement on input BTU's. If your air vent
is on the outside wall, you'd need 114 square inches.
Sealed combustion uses air directly from the outside and then vents the
waste gas out, using NO inside air for combustion. They aren't cheap, but
they are efficient, regardless of what that moron Nick says...
Will it be okay? I don't know. Your house was probably designed for a
water temp of 180°. Setting it at 140° will do for most of the times, but
probably won't be enough when the temps hit the design temprature. Outdoor
reset is like cruise control for your heating system. As the temps drop,
the water temps rise. At 65°, the water may be at 105°. At design
temp(5°?), the water temp would be at 180°. How much? I can't give you a
price from here.
Gas water heater? Your ROI on wrapping it with insulation woould probably
be 12-15 years. Insulating the hot water lines would be a good idea, IMO.
To set the temp, you need to get a good thermometer and correlate it with
Okay with R13? Around here, you'd be great. Where you're at, who knows?
I'd spend more time job hunting than talking to neighbors and surfing the
'net. Flipping burgers would make you some money, but I don't think you'll
be able to cut your gas bills enough to make up for the difference...
Sounds fairly useless, in an average US house that naturally leaks
2400ft^2x8x0.7ACH/60 = 224 cfm of air. The boiler might need about
10 ft^3 of combustion air per ft^3 of gas, something like 10x114
= 1140 ft^3/h, or 19 cfm.
So far, it seems the main advantage would be to fatten an HVAC installer's
wallet :-) You might say using outside air for combustion reduces the need
for winter humidification, but maybe the energy used to humidify air comes
back in the flue as more condensation, and winter humidification seems like
a bad idea for energy savings, in any case. You might say it's more efficient
to heat that 19 cfm from 30 to 70 in the boiler at 100% rather than in the
house at 98%(?), but that only saves 19x(70-30)0.02 = 15 Btu/h, no?
HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.