No more flooding (H2O)

August 27, 2013

Abstract

The time you need your sump pump the most is during heavy storms and extended rains, which is precisely the most likely time that either the sump pump will fail or your power will go out. A solution to this problem is presented.

Background

I had minor flooding into my unfinished basement twice, and a close call two more times. The first time it had nothing to do with the sump pump, it worked fine, but the burried sump pump exaust (put pic) could not deal with the massive amount of water during a hurricane, and ended up overflowing right next to the house's foundation instead of the normal 10-ft away from the foundation downslope. Luckily I caught it in time and connected a flexible hose to the sump pump exaust that routed the water 10-ft away from the house above ground. Within 15 minutes the sump pump cleared the one to two inches of water in my flooded basement. No damage, but I learned the lesson that hurricane preparation means bypassing the burried sump pump exaust because the ground can not absorb the water fast enough.

The second time the sump pump failed in the middle of another hurricane. I decided to check the basement before going to bed, and horror of horrors... the sump pump was not working despite the massive amount of rain. I watched the water quickly rise in the sump pit and made a frantic call for help to a good friend. He came an hour later with a spare pump, but the water was already one to two inches high all around my basement again, and rising. He decided to first clean the sump pit which was full of small rocks and other debris. After the clean-up we plugged-in my “failed” pump and it started pumping like crazy. The debris had simply blocked the water level sensor! Within 20 minutes the sump pump cleared the two to three inches of water. No damage again, but I was totally exausted. In the hour that I was waiting for my friend to arrive I was using a wet-vac to get water into a bucket and carry it up a flight of stairs. I though I could do it as long as necessary to keep my basement dry. WRONG! First of all, you can't keep pace with the rate of water coming down during a hurricane, and second, even if you could, water is super heavy. Try to carry a bucket full of water up a flight of stairs 20 times in a row and you are going to be exausted no matter how good a shape you are in.

After the second hurricane I thought “never again”. I was going to design a system that can't fail. But I neglected it, yet again. Then one fine summer Friday night while I was out and about partying, the skys opened and within the span of an hour we got record rainfall and had incredible gusts of wind (Stormageddon.) I decided to cut the night short and headed home praying the power was still on. Not to be. The power was out and would remain out for several days. Luckily, despite the massive rainfall my sump pit was totally dry. I guess you need sustained rain for water to start making it into the pit.

The final straw was when one day, before a major storm was to arrive, I went to inspect the sump pump. The pump was buzzing, but no water was pumped. It had finally failed after 15 years of faithfull operation. Given the sump pump unreliability reports I had read on-line, I made a mental note to get a replacement of this exact model (Hydromatic V-A1) as my long term primary sump pump; 15 years is not bad. In the mean time it had already started to drizzle and my sump pit was almost full of water. I went to my nearest Lowes and got myself a new sump pump. After a few hours of installation work that included several trips to Lowes for parts, the new pump was in place and worked through the storm like a champ. The lesson had finally been learned!

Maintaining Power

I don't care about having power for the refrigerator, TV, etc., during extended power outages. I just want my sump pump to work. 95% of outages are a few minutes to a few hours. This can be remedied with an uninterruptable power supply (UPS.) I already had a top of the line UPS, the Eaton PW9130L1500T-XL that supplied power to all my computers, monitors, and home theater system. The problem was that according to my calculations it could not sustain the sump pump for more than two hours during a power outage in the middle of a hurricane when the pump works for about 6 seconds every 30 seconds! That's a lot of pumping. The solution was to buy two Extended Battery Modules (EBMs) that plug in series into the UPS and provide enough juice for about 24 hours of such extreme pumping during unusually heavy rainstorms. I should note that the need for extreme pumping (6s every 30s) is unlikely to be required for 24 hours straight, so the UPS with the EBMs are likely sufficient to run the sump pump for several days provided nothing else is plugged into the UPS.

However, I wanted to be 100% prepared even for the most extreme of events. I researched on-line for top of the line generators and arrived at the Yamaha EF2000iS. Very reliable, very quiet, very good fuel economy, and very expensive. You get what you pay for. It provides a maximum output of 16.7 Amps at 120 Volts (2000 Watts) which can easily power the UPS.

I want to go over a few issues with the UPS setup. Those that might be tempted to use a small UPS that you can buy at your local computer store, pay attention!

First, a lot of the cheaper UPSes output a stepped square-wave waveform instead of a true sine wave, which does not play well with a sump pump motor. You want a UPS that outputs a true sine wave.

Second, motors draw significantly more current when they are starting up than during normal operation. If your sump pump is rated at 8 Amps and you plug it to an 8 Amp UPS you will overload the UPS which will result in either the UPS shutting down (if it's smart and can protect itself) or in UPS damage. You have to size the UPS, the generator, and the cables (UPS to sump pump and generator to UPS) accordingly!

The Complete Solution

If you are looking for a cost effective sump pump solution, this is not it! However, I have no doubt it's the most bulletproof system to carry me through even the most extreme of events. In addition, the UPS powers all my electronic equipment and the generator can serve as backup power when the skies are clear! Of course in the event the UPS is called to power the sump pump, all of other loads (TV, Computers, etc) must be turned off, to conserve battery power and have sufficient Amps on sump pump motor start up.

Approximate total cost: $3000

Note that you have to setup the Eaton UPS with 'site wiring fault alarm' disabled if you are to power it via a Yamaha EF2000iS that is not grounded.