Where to start looking for Energy Savings

[TradEddie]

No hot tub here.
I agree. The cold weather has brought an end to having to dehumidify the basement. I let it run for about a 30 minutes and checked on it every few minutes and it didn't fluctuate much from 600 watts. The low setting was only 50 watts lower than the high setting.

Doesn't your Kill A Wat have a button that shows the accumulated KWh, and the elapsed time? That's what you need to use for any cycling device, leave it on for at least 24h, preferably longer. If your humidifier really is drawing 600W at almost all times through the summer, you should look at addressing the source of humidity, not throwing cash away dehumidifying.

TE

 

[sloeffle]

To actually do the testing, you need to know 5 things...current and voltage, which you can measure at the panel, incoming loop temp, outgoing loop temp, and flow through the loop. This will measure everything, including pumping, blower, etc. It does not take into consideration duct losses, just the efficiency of the unit itself.

After we got the geo installed I asked the HVAC guy about permanently installing a temp / pressure gauge in the T&P ports so I could monitor the loop temps and pressure. He recommended that I not do that since the T&P ports are not designed to have something in them all of the time.

The HVAC company who ultimately did the install merged with another company and they are not responding to my calls. So I coincidentally have another company coming out this week to do a pre-winter checkup. It has been a few years since I have had the pressures checked. When I talked to the guy on the phone he said it sound like we have enough pipe in the ground and at the right depth for our furnace setup. I will see if I can the pressure and flow information from him.

To size a heat pump so second stage doesn't get used means you are paying more to run an over sized system most of the time.

If I remember correctly, we would of needed a 3.5 ton furnace for our heat and AC load. Waterfurnace does not make a 3.5 ton furnace. I made the call on going to a 4 ton unit.

The only unknown is how much heating your are supplementing with wood.

We generally burn around 1.5 cords of mixed hardwoods per year. Last year was a different story. The majority of the wood is White Ash. The wood furnace is EPA tested at 76% efficient.

24 million BTU/cord * 1.5 = 36 million BTU

36 million BTU * .76 = 27.36 million BTU

So of the 93 million BTU's that are being projected to heat my house roughly 29% of those are being supplemented by the wood furnace. It is probably less because the wood furnace does idle some and I would guess the EPA does not take that into consideration when doing their testing.

 

[sloeffle]

Doesn't your Kill A Wat have a button that shows the accumulated KWh, and the elapsed time?

Yes. I let is run yesterday for 4:42 and it consumed 2.27Kwh of electric. I probably should of let it run longer but I am kinda of cheap a$$ and turned it off.

you should look at addressing the source of humidity, not throwing cash away dehumidifying.

The rim joists and sealed with closed cell foam down to the second block. The walls are sealed on both sides. It is a walkout with a door. The door has low E glass in it and has also been sealed with foam and caulk. The sump crock is not sealed but I have that on my to do list. Unfortunately I think it is just something you have to live with if you have a basement.

Is there anything I missed that could be causing high humidity in my basement ?

 

[woodgeek]

The rim joists and sealed with closed cell foam down to the second block. The walls are sealed on both sides. It is a walkout with a door. The door has low E glass in it and has also been sealed with foam and caulk. Unfortunately I think it is just something you have to live with if you have a basement.

Sounds like you have one of the best engineered basements I have ever heard of. And lots of people with crappier basements do NOT need to dehumidify at all. I assume you have no bulk water intrusion (i.e. flooding), no sump pits, and you are conditioning the space to the same temps as the rest of the house year-round, and it is not insulated with respect to the house. If the above is true (and the airsealing install is ok) there is no good reason for a humidity problem. At all.

 

[maple1]

I have a full basement and a humidifier. It hasn't been out of it's box for 3 or 4 years now. The only time I used it was if I got caught by the weather in the fall and ended up having to move wood in that was damp from recent rain - I would set up the humidifier by the wood pile & run it for a month or so. Last 3 or 4 years the Venmar does the job and I've been watching the weather closer the month before I move my wood in.

EDIT: What do you have for ventilation in the house?

 

[sloeffle]

Sounds like you have one of the best engineered basements I have ever heard of.

Thanks. The foam broke our budget but IMHO it is worth every cent.

I assume you have no bulk water intrusion (i.e. flooding), no sump pits, and you are conditioning the space to the same temps as the rest of the house year-round, and it is not insulated with respect to the house.

No water intrusion. The basement was back filled with river rock and then about 6 inches of topsoil. Basement concrete floor is not insulated but it does have about 6" of river rock under it along with 6 mil plastic. We do have a sump pit that is open to the basement. The basement is naturally drained but I put a sump pit in just in case gravity stopped working. Looking back it was probably a bad decision. I should've listened to the excavation contractor. House has gutters.

Next summer I will have to put a hygrometer in the basement and see if it actually needs dehumidified. If we don't run the dehumidifier the basement gets musty after a week or so. It could definitely use more HVAC though. I only have one 6" duct for a 768 sq ft basement.

 

[sloeffle]

EDIT: What do you have for ventilation in the house?

We do not have a HRV or any type of active ventilation. We try to keep the windows open as much as possible when weather permits. During the winter we will sometimes crack a window or door.

 

[woodgeek]

The uninsulated slab could be pulling down temps a bit (toward seasonal earth temps). I would prob just upgrade the HVAC connections to get more conditioned air down there in the summer.....you might also push some of the excess heat down there upstairs in the winter. Any small bump in AC usage would be tiny compared to the dehumidifier usage.

The geyser would also help.

Have you screened for Radon?

 

[woodgeek]

We do not have a HRV or any type of active ventilation. We try to keep the windows open as much as possible when weather permits. During the winter we will sometimes crack a window or door.

Ah....you might have too much humidity upstairs sometimes, and the basement, as the coolest part of the house gets musty first. But it isn't the basements 'fault', its too much RH upstairs.

I'd at least put in bath/shower fans. I also put a timer on one of mine to cycle 30-40% in the spring/summer/fall when we needed a little more air. Good budget ventilation solution.

 

[sloeffle]

Have you screened for Radon?

We have not tested for radon.

No problems with humidity in the winter as the the wood furnace tends to dry out the house. We actually run a humidifier in the winter.

But it isn't the basements 'fault', its too much RH upstairs.

I will have the HVAC guy verify the fan settings on the furnace this week. They possibly could be set too high so the house is not being properly dehumidified in the summer by the A/C. Our thermostat has an option that runs the fan 15 minutes every hour. During the summer I usually have that on but not so much in the spring and fall since the windows are usually open.

Where did you get your timer at ?

 

[TradEddie]

Next summer I will have to put a hygrometer in the basement and see if it actually needs dehumidified. If we don't run the dehumidifier the basement gets musty after a week or so. .

You will probably find that you don't need to run the dehumidifier flat out. Even prior to airsealing, insulation or Geospring, my humidifier needed to run perhaps 5% of the time to prevent mustiness. One expensive mistake people make is trying to keep a basement at the range of RH recommended for occupied living space, or valuable archives. All you need to do is keep the humidity at a level where there is no condensation on the coldest surface, likely the floor in the corner with the least air movement. For this, you need to think dewpoint, not RH. If you could find an inexpensive hygrometer that displayed dewpoint, it would be ideal (and let everyoen here know the details). Keep the basement dewpoint below the slab temperature, and you should have no problems. For reference, my basement RH is often 70% in Summer, and I don't have any mold or mustiness problems.

TE

 

[woodgeek]

We have not tested for radon.

No problems with humidity in the winter as the the wood furnace tends to dry out the house. We actually run a humidifier in the winter.


I will have the HVAC guy verify the fan settings on the furnace this week. They possibly could be set too high so the house is not being properly dehumidified in the summer by the A/C. Our thermostat has an option that runs the fan 15 minutes every hour. During the summer I usually have that on but not so much in the spring and fall since the windows are usually open.

Where did you get your timer at ?

Google 'Aircycler SmartExhaust'...got mine at some HVAC internet outfit.

 

[sesmith]

Sloeffle,

I just realized my confusion. Sorry. Early on, you posted your hourly heat load #. Somehow I managed to read that as 60 Mbtu...a yearly #. So the confusion as it just didn't add up. I think senility may be rearing it's ugly head Using your yearly real # (93Mbtu), it all fits, ruling out any heating issues, even with the wood heat use during last years cold winter. Your house is obviously pretty air tight and well insulated. Your average electric use is right in line with what the geolink report expected your hvac system to use. I'm even now more sure that you won't find any major electric users lurking.

 

[TradEddie]

No problems with humidity in the winter as the the wood furnace tends to dry out the house. We actually run a humidifier in the winter.

That's a favorite old wives tale, no matter what you have heard, a stove does not and cannot remove moisture from the air. There were once reasons why stoves were indirectly responsible, but unless you live in a drafty old house with an equally old stove, you should not need any more re-humidification because of a stove than if you were using central heat. The one caveat is that stove heated houses are often warmer, thereby reducing the relative humidity, but not actually reducing the moisture.

TE

 

[woodgeek]

Indeed. Needing to humidify in the winter can allow you estimate leakiness. @sloeffle, big whole house humidifier or a smaller unit?

 

[sloeffle]

That's a favorite old wives tale, no matter what you have heard, a stove does not and cannot remove moisture from the air.
TE

I learned something today. I probably should invest in a hygrometer that shows RH. Maybe the house really isn't that dry in the winter or as moist in the summer as I think it is.

We just run a cheap one gallon per day humidifier when we are home.

 

[semipro]

That's a favorite old wives tale, no matter what you have heard, a stove does not and cannot remove moisture from the air.

That's a really good point.
Although I would posit that a stove without a outside air supply might contribute to a change in the moisture level in a house through increased infiltration.

 

[TradEddie]

That's a really good point.
Although I would posit that a stove without a outside air supply might contribute to a change in the moisture level in a house through increased infiltration.

Sure, to some extent, and so would any gas or oil burning furnace without external air supply. It was possibly once more of a problem with old-fashioned woodstoves burning unseasoned wood because much more air was needed than a modern stove in a tighter house. I've watched the humidity in my house when running the stove and the slight drop is wholly attributable to the rise in the room temperature, the underlying dewpoint is unchanged. That isn't to say that the resultant lower %RH couldn't affect sinuses or fine furniture, but adding more moisture could lead to bigger problems when the temperature drops again and %RH goes above desired ranges.

TE

 

[sloeffle]

Geo Update:

The geo tech said that my setup seems correct in her opinion. She said it sounds like we have enough pipe in the ground and at the proper depths. Fan speeds looked good. She did say that if we ever have to replace the furnace she would opt for a 3 ton since we were on the fence. A 3 ton would give us better dehumidification and less swing in temperature.

Temps:

50F inlet temp
45F outlet temp

Pressures:

35 PSI inlet
26 PSI outlet

The furnace had very little pressure when she got here. She had to put about a quarter gallon of water in the loop to get it up to pressure and recommended buying a T&P gauge to monitor. If the pressure drops down again then I will call them in the spring and have the loop re-pressurized. It sounds like all of the air might not be out of the loop. The loop was pressure checked for 48 hours during install.

DSH:

She recommended turning if off in the dead of winter since you are robbing BTU's to heat water away from heating the house.

The Nyletherm is here and I will hopefully have it installed by the end of the weekend.

 

[moey]

We have a all electric house with a 5 ton climatemaster geo system little over 3000sq ft conditioned 2 adults 2 small children. We average around 900kw during the summer months we rarely run our A/C so I would not include that in any comparison. We run our dryer a lot at least it seems we do. During the winter months the highest kw usage we had last year was 2500kw last January.

Id question why you lost pressure the only time I have lost pressure was when I had a visible leak where there was a clamp. Hope you dont have a leak somewhere.

 

[Doug MacIVER]

this is a question on suppliers. the local nasty grid rates in Mass are going up significantly from$.10/kw to .20/kw. getting calls from 2 suppliers at this point. we have also started to explore Viridian Energy. my small business here uses about 3000kws in the winter months. any experience here with these alternate suppliers, are they fly by night or legit?

 

[moey]

this is a question on suppliers. the local nasty grid rates in Mass are going up significantly from$.10/kw to .20/kw. getting calls from 2 suppliers at this point. we have also started to explore Viridian Energy. my small business here uses about 3000kws in the winter months. any experience here with these alternate suppliers, are they fly by night or legit?

I have no experience but read the fine print as to what happens at the end of the term. Around me when I explored one to save about $.5 kw/hr there were some bad stories on trying to switch before it went to variable rate all of a sudden the company was not very responsive. Folks would get stuck paying one month at a very high rate.

 

[sloeffle]

Hope you dont have a leak somewhere.

Yes, I hope not too. The loop was pressure tested to 50SPI for 48 hours after it was put in. Hopefully it just air in the loop from when it was filled. Overall I have been very happy with the geo. The heat is okay, but the A/C is great.

We pay .16Kwh and are part of a co op. So no electric shopping here.

 

[semipro]

The plastic piping used in the ground loops is not totally impermeable, especially to gases. If you had some air trapped in the system it could "leak" out and pressures would drop a bit.

 

[sesmith]

Some info here on pressure drops:

(broken link removed)