Zoeller M53 - 1/3 HP Cast Iron Submersible Sump Pump w/ Vertical Float Switch

An air relief hole in the base portion of the pump to help prevent air lock within the pump. Even with this air relief hole in the pump, it's still highly recommended that you drill a "weep" hole in your discharge pipe. The "weep" hole as it is called should always be drilled in your discharge pipe to prevent an airlock. This is true in sump and sewage applications. Air locking on a sump pump happens when there is air between the pump and the check valve of the discharge line. The trapped air prevents the impeller from drawing in enough fluid to open the check valve to allow discharge. The weight of the fluid on the topside of the check valve keeps it closed. The problem is often noticed after the initial use when the pit has had time to dry out during a dry spell. When it gets water in the pit again, the airlock condition shows up. The pump runs due to the float switch being raised, but can't eject the water because of the airlock condition. I suggest that you drill a 1/8" or 3/16" hole in your PVC discharge pipe, approximately 4" above your pump's discharge port and well within the inside of the basin. Drill the hole at a 45-degree angle so the hole is pointing toward the bottom of your sump basin. Water will be discharged from the weep hole when your pump is operating. This is completely normal.

A typical installation will have the check valve positioned about 2-3 feet above your sump basin cover. If the check valve is screwed directly into the sump pump's discharge port, there is really no place to drill the weep hole, but also less of a chance of airlock due to the positioning of the check valve. The only problem with installing the check valve directly into the pump's discharge port is that it takes more power and effort for the pump to start due to the added weight of all the water sitting above that check valve, especially if your head is 8 feet of higher. When the check valve is installed above the basin cover, it reduces that starting power and also makes for a much easier method of replacing or performing maintenance on your pump and system.

Based on your description, it sounds like the M53 is ALMOST taking care of the situation, but not quite. IF you have more water than sand, that M53 will handle it.  I would suggest increasing the discharge piping from 1-1/4" to 1-1/2" or even 2". If this doesn't do the job, you might increase to the 1/2HP M98 Zoeller pump with the same 1-1/2" or 2" discharge. The 2" discharge WOULD require an adapter for either pump discharge, but should help.

Regarding the noise concern, there should not be any difference as long as the pump is installed properly. Regarding your cycle rate, it may actually increase since it will be emptying your basin quicker. It's always best to keep your cycle rates to a minimum when possible. So if the M53 worked well for you and you never came close to flooding, I would suggest keeping that 1/3HP pump in place. IF that M53 had difficulty with demand at any time however, then I would suggest increasing to the 1/2HP model M98.

It's always recommended that you drill a weep hole in your PVC discharge pipe with a bottom suction pump. The relief hole in the pump will help prevent any air lock within the pump. The weep hole will help to prevent any air lock within your discharge pipe between the pump and check valve.
If you have any other questions, please let me know.

That's a tough question to answer. Typically, the pump should give you about 5-7 years of life in a standard sump application. That said, I have heard of them lasting 10, 15 and 25+ years in some cases. The switch is the most common reason for failure and can be replaced, though it is a bit involved on the "M" Series models.
If you have any other questions, please let me know.

None, whatsoever. The "D" designation is for the period of time in the past, that it was manufactured. The "D" series was manufactured between 7/92 and current.

Thank you for your interest in Sump Pumps Direct. As with any question that I get on wiring pumps, I must refer you to the fact that all manufactures do state the following:
Make sure the pump electrical supply circuit is equipped with fuses or circuit breakers of proper capacity.
A separate branch circuit is recommended, sized according to the “National
Electrical Code” for the current shown on the pump nameplate.

Thank you for your interest in Sump Pumps Direct. One of the advantages to pedestal pumps is that you have the ability to adjust the float switch to allow the pump to evacuate more water out of your pit per cycle, thereby reducing the number of cycles per hour. Introducing a submersible pump like the Zoeller model M53, should give you a quieter pump but it may very well cycle more frequently than your current 1/3HP pedestal. One option you could look at to overcome this, would be to install the non-automatic version MODEL N53. You could then install a separate electronic switch like the Pro Series Ultimate Sensor Digital Pump Controller System, model USC3 or the HydroCheck Electronic Hi-Lo Pump Switch, model HC6000. These "piggyback" style switches will give you the ability to fine-tune the ON/OFF levels for your pump operation.

Typical installations will include the discharge PVC Sch40 pipe screwed into the pump discharge port and extending approximately 2-3 feet above the sump basin cover. At this point, you could attach the check valve and then complete your discharge configuration. This method would allow for an easier access point for you to service your pump.

Thank you for your interest in Sump Pumps Direct. The discharge on the Zoeller M53 is 1-1/2" and as such, you should resort to that same size piping to achieve optimum performance and pumping capacity. If you must reduce the piping, I don't recommend that you go any smaller than 1-1/4". Reducing it further will only create more backpressure on the pump which will reduce the pump life, not to mention the reduction in pumping capacity that you would realize.
The check valve placement can be anywhere from the discharge port of the pump to about 2-3 feet above the sump basin cover. The latter is my suggestion as it also allows for a good place to gain access to your system for service.
If you have additional questions, please let me know.

All sump & sewage pumps need to be wired according to national electrical codes and all applicable local codes and ordinances. When in doubt, you should contact a licensed electrician in your area.
Pumps are not to be installed in locations classified as hazardous in accordance with National Electrical Code, ANSI/NFPA 70.

Thank you for your interest in Sump Pumps Direct. It really depends on how you plan on getting the water into the sump basin. If you are doing a typical basement INSTALLATION, I would advise something more like the Zoeller model M53 or M98, depending on your water table. I would then suggest installing a standard SUMP BASIN and COVER. You can then tie this in to a french drain or you can drill holes in the basin to allow the water to seep through and into the basin for discharge by the pump. If you are looking to install this system outdoors or in a crawl space, the Liberty 1/3 HP Cast Iron Crawl Space Sump Pump Kit, model CSP-257 might be a better choice.
And don't forget the CHECK VALVE.

Zoeller basically builds 2 models, the 1/3HP model M53 and the 1/2HP model M98. The 1198 number most likely refers to the date code. If you cannot locate the model number in the same area as the date code, the 1/3HP model is about 10" tall and the 1/2HP model is about 12" tall. I would also suggest replacing your CHECK VALVE as well.

The Zoeller M53 is and has been a great pump for many years! It is designed to handle a maximum of 15 feet of vertical lift. I have heard of this pumps lasting for 10, 15, 20 and even up to 30 years. Chances are that the switch has failed and needs to be replaced, which is a common occurrence. We do offer the Replacement Mechanical Switch for M53 and the Zoeller Complete Cover Assembly & Switch Kit For M53 Sump Pump. Please note however that the switch requires installation by you or a certified plumber/contractor and ALL SALES ARE FINAL - NO RETURNS ALLOWED ON THIS PRODUCT.

There is a rubber gasket between the switch housing and pump housing that form a water-tight seal to protect the switch connections. If water has seeped into the switch housing, this would certainly compromise the performance and safety of the pump and I would highly recommend replacing the pump. Under normal operating conditions, it is NOT uncommon for the pump and switch housing to be completely submerged.

The M53 has a cast iron switch case, motor and pump housing with an engineered thermoplastic base and an engineered, glass filled, plastic impeller with metal insert where as the M57 is all cast iron construction including the impeller. Other than that, both pumps are the same.

The minimum sump basin size relates to the minimum size of your sump basin or pit, that a specific pump will safely operate in. Any pump needs a certain amount of space due to "on/off" levels, cooling factors and cycling that the pump is designed for. Most pumps will require a standard size basin of 18" wide by 24" deep but some will also operate in smaller basins. You want to pay very close attention to these requirements as they will insure a longer pump life.

The normal life of a sump pump is about 7-10 years, though I have heard of some going 10-20 years and more. Zoeller pumps are known to last but are also known for some switch problems. Please note that all manufacturers do recommend that you inspect your pump and basin every 3-6 months to insure that they are working properly. That being said, you can make the call on weather you would like to replace the pump or the SWITCH. If you decide to replace the switch, please be advised it would require installation by you and ALL SALES ARE FINAL AND THERE ARE NO RETURNS ALLOWED ON THIS PRODUCT.

The only maintenance that is required is what all manufacturers recommend. And that is to inspect your pump, float switch and sump basin every 4-6 months to insure that they are operating properly and there is no debris in your basin that could impede the pump or float switch operation. Oil should NOT need to be added at any time unless the pump develops a leak which is pretty rare. If that should happen, it's usually easier to have it serviced at a local authorized Zoeller service center or replace the pump.

Unfortunately, I would not have the answer to that question. We are an online retail store that sells and ships many different brands of pumps all over the United States. We are based in Bolingbrook, Illinois and only operate out of this single location. You might try looking at our listing of manufacturer contact PHONE NUMBERS to find the manufacturer of the pump that you are interested in and then calling them for assistance on finding a local dealer.

While the Zoeller pumps are one of the better pumps out there, they are not very efficient. The M53 runs at 9.6 amps and requires 25.9 amps to start. When using the formula of amps X volts = watts, you would need a minimum 1152 running watts and 3108 starting watts to operate your pump. When using generators, you should never load them up any more that 80% of their capacity at any time, so you might consider a generator with about a 4000 watt starting watt capacity.

There is usually a brass tag mounted on the top side of the pump between the the power cord relief and the float switch arm that will give you the model number and date code in addition to the voltage and amps. If that is not visible, you can measure the height of the pump. The 1/3HP model is just over 10 inches tall and the 1/2HP model is just over 12 inches tall.

That really depends on the pump. Some are more efficient than others. For example, the 1/3HP Basement Watchdog model BW1033 has a running amp rating of 3.5 and a starting amp rating of 7. When you figure the watts by the formula of amps times volts equals watts ( A X V = W), you get 420 running watts and 840 starting watts. But when you look at the Zoeller 1/3HP model M53, that pump has a running amp rating of 9.6 and a starting amp rating of 29.6 or 1152 running watts and 3552 starting watts.

Pump warranties vary from 1 year to 5 years depending on the pump and the manufacturer. That being said, all pumps should last a good 5-7 years or more providing they are installed properly.

You might try to brace and/or pad any area of the discharge pipe that may be coming in direct contact with any walls, ceilings or joists to try to reduce the vibration that is being caused by the sudden reversal of the water flow once that pump switches off and that check valve slams shut. Sometimes you will need to install a check valve with a spring-loaded rubber flapper like the PeakFlow model PFQCCV15 Clear Quiet Check Valve 1-1/2" or the Basement Watchdog Klunkless Check Valve. These check valves should help reduce the "thumping" sound if they don't eliminate it all together.

You are describing a fairly common application. A lot of homeowners will install 2 sump pumps in their sump basin for this type of situation. The main pump will be set to activate at about 12 inches of water and the secondary pump will be set to activate at about 14-16 inches of water in the event the main pump cannot handle the amount of water coming in. Please note however, that you will also need protection in the event of a power outage. In that case, your best defense is a higher output BATTERY BACKUP SYSTEM or a small STANDBY GENERATOR.

The switch on the Zoeller M53 has about a 4 1/4" differential so by raising your pump in your basin, you will effect the level at which the pump will activate, however you will NOT effect how much water is pumped out. Your only option would be to either replace the pump with a different type of switch, possibly a tether or electronic switch or by rigging the switch on your M53 to stay on and then add another "piggyback" style switch. The Pro Series model USC3, the Superior model 92005 or the StromPro model ING-2-10-1B switches would all give you the capability of adjusting the actual runtime of your pump.

Without knowing more specifics like the water table, area of the country you live in, actual square footage of your basement, etc., it really is difficult to answer. I can tell you that most average sized homes in an average water table area can usually get away with a 1/3HP or 1/2HP pump. Beware of over-sizing the pump as it could cause the pump to cycle too frequently thereby reducing the life of the pump. You don't want to just install a 3/4HP or 1HP pump just for the sake of it.

Unfortunately not however, the
N53 non-automatic model does come with a 15 foot power cord. You would just need to purchase the float switch of your choice separately.

Yes, you can, but you need to purchase it direct from Zoeller. You can reach them at (800) 928-7867.

The starting amps for the M53 are 25.9. You would really need to know the starting amp rating for your ice box to get an accurate number to size your generator. The 6.5 amps you mention are the running amps. The compressors on the icebox always require more amperage or power to start because of the extra torque needed. Once you can obtain that number, multiply it by the voltage (120), add 3108 (the starting watts for the M53 pump) and add 20% to the total. That would tell you exactly what size generator you would need to run both appliances at the same time. Amps times volts give you watts.
I can ASSUME that the icebox would be in the neighborhood of 32 amps. At that rate, together with the sump pump running at the same time, I would estimate that you would need between a 6000 and 7000 watt rated generator. If you can get away with switching between the two appliances, you could go with a 4000-5000 watt rated generator.

That answer would be based on how much water you feel you would need to pump during a power outage. The 507 will pump 900 GPH at 10 feet and the 510 will pump 1320 GPH at 10 feet. We do carry other brands that will also be compatible with your pump and are capable of pumping more if you feel you need it.

A better selection might be one of THESE as it would be better suited to the application. You might also check out this TRANSFER PUMP if you prefer an electric alternative.

These Zoeller submersible sump pumps have a factory set pumping range and are unable to be adjusted to accommodate a higher water level.

In most cases, if your pump keeps running, it is most likely a switch problem.

The M53 is the most popular 1/3 HP Zoeller pump, so it would probably be safe to say that's the model.

Normally a pump should last 7-10 year, but to be on the safe side, it's usually best to replace a pump after it reaches the 5-7 year mark.

Hello Bill,
It's possible there is some debris in the switch mechanism that may be causing the switch to fail. You might want to give Zoeller Tech Support a call at (800) 928-7867. Those pumps do carry a 1 year warranty.

The interior dimensions of a basement aren't a major factor in sizing a sump pump correctly.

Monitoring your current pump during normal operation and during a storm can give you a better idea of what size pump you would need.

A vertical float switch is a ball that floats above the water. As the water level rises so does the float which, at some point, it will trigger the switch to turn the pump on. This float has limited movement up and down and side to side, giving it less freedom of movement and less of a chance to get stuck as a tethered float would.