Ideas for Insulated Well/Pump House?

Hi Permies,
I was hoping some of you might have some ideas or even some plans/designs(?)... I will be needing to build a new pump house (well house) and I don't really know where to start. I am in zone 6, so we get cold winters, and I want to build something well insulated that will keep all the well-system parts from freezing. Perhaps something that makes use of the ground heat (Earthbermed? underground tubes?) would make sense. I want the structure to be big enough to work on the system easily (not crawling into tight spaces), and wellhead itself will need to be accessible in case it needs servicing (again) which they do from above. I saw one diagram where the well head was actually OUTside the well house, and the water pipe coming out of the well ran deep enough underground that it was fine outside the structure.

There is a pressure tank, various valves (going to different areas of the property, and the electrical that will need the protection. And I suppose it would be smart to have room in there for a generator for backup purposes. I plan to install solar panels so I can pump the well without the generator. But in the current situation, the pump (388 feet down) is run on 220v, so does that mean I have to have an inverter for the solar? Will that take a lot of solar panels? I was hoping not to have to install batteries (expense and eco-dismal), so if no batteries, then I would not have the option for a night time lightbulb to keep things cozy. I certainly could paint the exterior a dark color to collect heat during the day. I am in Northern Arizona, so we get lots of sunshine even in winter. Any suggestions would be greatly appreciated.

Cheers,
Jennifer

Well I think the place to start if you are on well water is a slinky type geo-thermal glycol closed loop that is used for radiant floor/wall/ceiling heating/cooling, domestic hot water, and Energy Recovery Ventilator tied loop for a energy efficient air sealed mass earth construction above ground building. I believe that branch of the system could be PV tied with little to no AC. Do you have any idea what your ground temps are there annually @ 4-6 feet?

220v AC will definitely need an inverter, as solar only provides DC, also, yes, you would need batteries. Small PVAs generate relatively little of power, which is typically stored in batteries so larger loads can be run. You might charge your cell phone from a solar panel, but even then it's better to charge a battery to use when charging the phone. The number of solar panels (and batteries) will depend on the current (amperage) draw of the pump and the amount of run time. Deep well pumps use a lot of amps. You would probably be better off using the generator as you would be looking at a pretty significant solar installation for a deep well pump.

I don't have much experience heating a pump house, hopefully someone else here can give you advice on that aspect.

You need to find out where your water table is and ground temps for starters here: http://websoilsurvey.sc.egov.usda.gov/App/HomePage.htm

from there your pump and pv requirements could be sized. You can drop your heating and cooling, electrial loads to practically nothing if you know how to design energy efficient building's. I'm not the most popular guy with the HVAC contractors Everything is going DC and/or highly efficient heat pumps or electric resistance as inefficient as it can be these days it still can make the most sense.

I don't have much experience heating a pump house, hopefully someone else here can give you advice on that aspect.

I have a huge background in mechanical design at a reasonable rate give me a call anytime.

Jennifer, I have a property in Colorado, zone 6, and was going thru exactly the same thing. I had a well and a nearby shed that housed the pressure tank and subdrive. The well was used for irrigation only in summer.
last fall we finished construction on the guest house/garage and needed to have year-round water. I have lots of experience with well equipment and did not want to put the equipment in the house or garage
because of potential water damage. I spoke to local farmers to see what they do to solve this problem. Most people had equipment under houses in crawlspaces or other hard to access places. My requirement was
to have enough space to comfortably work on the well equipment, no expensive additional heating system to keep from freezing, easy access, and well head had to stay above ground.

Some people (including my wife) thought my solution was "over the top"! I believe that if a job is worth doing, it's worth doing extremely well. My solution was to build a cube out of 2x6's and bury in the ground, with an insulated man well
to gain access. The cube is 6' x 6' x 6' outside dimensions, a little over 5' x 5' x 6' inside. the access well is 3'x3' inside dimensions by 10' tall. I had an engineer friend figure roof support for 2' of soil, it came to 4 beams each consisting of 4 2x6's nailed together. I rented a backhoe and dug a hole 10'deep and 10'x14' and put a couple of inched of drainrock in for the floor. Walls were 2x6 12"oc so they lined up under beams. I had extra geofoam from the house 6 - 4'x8'x6" for insulating the roof.

I used 1/2" plywood for walls and covered with 6mil plastic. I ran water pipes in low, 6' under ground. I ran a single 220VAC circuit for well and 2 20amp 110VAC circuits for lighting and power. I only had the backhoe for 2 days so only 1 pic my wife took since I was so busy building.

Here is a pic of my "ridiculously big hole" with drain rock, and water and electrical lines



I backfilled up to the roof, put the foam on (18") letting it overhang, and put 18" of soil on top of that. The man well extends about 18" out of the ground, and has a cover plus 18" of foam sitting on a 2x4 ledge so it is in line with the roof insulation. There is also a piece of plywood for a door into the cube. When I was there we had a week of 10degree days and the pit was a steady 50 degrees. Temps dropped to below zero during the winter but temp was steady inside cube.

There is obviously enough ground heat to keep well equipment from freezing, our frost depth is around 32", pitless adapter is set at 4'.

This project was a lot of work but met all of my requirements. I would definitely consult with an engineer before attempting this yourself, just to be safe from cave-in. Be careful, "well pits" are not considered legal in most places, these usually had well head underground as well and posed a contamination hazard if the well pit floods. My setup did not change well head, it just placed the equipment underground in a freeze proof room.

Additionally, home depot sells a small electrical 3prong splitter that has a thermostat built in to turn equipment on and off at set temperatures, its cheap and could power a small space heater if needed.

Model # TC3
Internet # 100210525
Store SKU # 527857
120-Volt Thermocube Thermostatically Controlled Outlet

Thank you everyone for your ideas. This is being very helpful. I went and had a good look at the well head yesterday, and I realize the pipes coming out of the well are coming right out the top instead of lower down (where they would be more protected). Hmm. So my thought of putting the well head itself outside the shelter won't work. It all has to be inside.

Steve, good reality check on the solar. As a newly to solar, I naively think it can be all simple and minimalist, but that is a deep well to pull from.

Terry, I couldn't find the soil temperature info--I went to a map, but got lost. A local said that the soil is around 55 degrees and the frost depth is max 2 feet. Then on a global soil temp chart, it said that at 4-5 feet, the temp was 52, so that is probably more accurate, but I didn't find any thing specific to this area (East of Snowflake, AZ). Water table I believe is around the water depth of the well which is 388 feet down.

I always like ideas where there is less likelihood of failure... i.e. those ideas that take advantage of the laws of physics at the basic level. Kevin, I would love to see your picture, but for some reason it is not showing up on my screen... not sure if it is an issue on my end? Does it show up on your computer? I will be inquiring with a local well driller as well, and will find out if there are any code issues with the 'man well' idea. Kevin, in your case do you need to provide access to the well head if it needs servicing? I would need to have a hinged roof section or some way of accessing the well head from the top, since there has already been a need to do this (which left a big cut hole in the roof of the old structure!)

I will do some more local inquiries and post anything noteworthy.

Hi Jennifer-

I just had a quick question about your situation. You've said you well pump is 300+ feet deep. What is the static level of the well? that is the depth that the water surface level in the well is. That is the depth that you need to calculate you from for pumping distance.

For example, if the well is 500 feet deep, but the static level is 50', then you only need a pump powerful enough to pump from 50', even if the pump is 450' down. Also helpful to know the recharge rate. If the static level is at 50', but the flow rate is only .5 gpm, then you'll need to consider how much water you'll pump for a given time before the static level returns to 50'. This might require a larger pump.

I would bury the water pipes from the well to building under the frost line (2ft).
What is the size of your pressure/storage tank.
If it is completely refreshed/emptied/drained and refilled with 55F water daily, then even in zone6 it shouldn't freeze if the shed if properly insulated.

They have 300W solar panels, for $300 and if you have 5hrs of sunlight in the winter that is 1500w/day.
You can get the cheapest $100 square-wave inverter, motor/pump can handle the noise unlike electronic.

So Dale, the well is drilled to 438' and the water level at the time of drilling (1994) of 388'. There is an 80 gallon steel pressure tank, a 3000 gallon storage tank, and a Franklin electric 1 HP control box (S Bengi, will that be able to handle the 'noise' of the square wave inverter?). The recharge rate for wells in the area is around 35 GPM, and the flow rate of the pump is rated at 6 GPM, and we observed close to that, maybe 5.

We were thinking of setting the system up so the ground water goes to the storage tank first, before going to the pressure tank, but then the temperature would be much colder in the pressure tank. Thoughts on this?

S Bengi, I agree about burying the pipes... I have just learned that I can re-rig the top of the well by installing a pitiless adapter, so the water comes out below the frost line. That way I CAN put the wellhead outside in case it needs servicing, and all the other stuff would be inside the insulated shelter. Thanks for the details on solar stuff... that give me hope. Oh, and we definitely have 5 hours of sunlight during winter... and just the occasional weather system.

Simplicity is good design, you can spend a ton on over engineered design but the Amish here just build theirs in basements like a small shed underground with a roof that is a foot above grade......let nature insulate.....

Use an excavator to dig a ramp into a drilling area that is 5-6 foot below grade, then build the walls around it and backfill.

550 Amish families here can't be wrong, it works in -15........we are zone 5b

So your well head and vessels all are housed underground in an 8x8 or so basement, no freeze, no worries! If you had to worry you could burn a 100w lightbulb to warm the room in terrible weather.

In all you might be talking an additional $1500 in materials if purchased from box stores.

Maybe you could keep your pump house above grade and put dirt on top. Build yourself a hill. Would probably be easier than excavation and forming and dealing with possible groundwater seepage getting into your pump house.