| Unit | Size | Supported weight | Motor | Workouts | Warranty |
|---|---|---|---|---|---|
ProForm 520 ZN Check Discounted Price | L:72" W:36" H:57" | 300 lbs | 2.5 CHP, 1-10 MPH | 18 | Frame: lifetime Motor: 25 years Parts: 1 year Labor: 1 year |
The ProForm 520 ZN is basically the same model as the ProForm ZT6. The only difference between these two models is the console display. The 520 ZN model features a smaller one. Also, before we proceed with the detailed presentation of each one of its features, another aspect requires clarification. This is the 520 ZN, part number PFTL59614 which is not iFit compatible.
Technical Details and Specifications
- Assembled dimensions: 73L x 36W x 57H inches (185L x 91W x 145H cm)
- Tread belt dimensions: 55L x 20W inches (139.7L x 50.8W cm)
- Assembled weight: 190 lbs (86 kg)
- Supported weight: 300 lbs (136 kg)
- Motor: 2.5 CHP Mach Z Commercial Motor
- Incline: Automatic, 0-10%
- Deck cushioning: ProShox
- Speed levels: 0-10 MPH
- Console: 18 workout programs
- Amenities: Sound system, cooling fan, tablet holder, 2x bottle holder
- Warranty: Frame lifetime / Motor 25 years / Parts 1 year / Labor 1 year
Deck construction
First of all, this treadmill features a folding design. Its deck folds up and connects to the left console mast with a locking latch. It doesn’t have a hydraulic, soft-drop mechanism such as the Schwinn 870 for example. Therefore when unfolding the unit, it’s vital to 
lower it yourself carefully. Also, even though folding it isn’t too difficult, since the machine’s deck is rather heavy, you should be able to lift at least 50 lbs (22.5 kg).
This treadmill features a 3/4 MDF phenolic deck, sturdy enough to support users up to 300 lbs (136 kg). Even more, it’s actually a running treadmill, both its deck and motor can support users up to this weight without any problem.
Similar to the ZT6 model, the deck on the ProForm 520 ZN model integrates a 2-cell (on each side), ProShox cushioning system. This suspension system helps alleviating the impact on the joints, up to 30%. In other words, even though a workout on this treadmill may not have such a low impact as a workout on an elliptical machine, the running deck still provides less impact than running on a concrete or asphalt surface. On the other hand, even though this suspension system is present, the deck shouldn’t overly flex.
The running surface of this machine is 55″L x 20″W (approx. 140 x 51 cm). It’s long and wide enough to accommodate users up to 6’2″ – 6’3″ (188-190 cm), for running workouts. Of course, if you’re taller you’ll still be able to run on it as long as you don’t exceed the specified weight limit, but in this case the treadmill may feel a bit small. The running surface is given by a 1-ply, industrial, stretch-resistant belt. Also, the deck uses 1.9″ (5 cm) crowned rollers, with sealed ball bearings, for a superior grip on the tread belt.
Frame construction
Since the machine weighs approx. 190 lbs (86 kg), it’s pretty obvious that the frame is steel-made. The front metallic base of the frame features two adjustable stabilizers and two caster wheels at the rear, to facilitate the transport of the assembled and folded machine. The rear part of the deck also rests on two adjustable stabilizers, covered by plastic shrouds.
This ProForm treadmill features a rather large footprint, taking 73″L x 36″W (185 x 91 cm) of floor space. When the deck is folded up, the machine rests on the front steel base of the frame, remaining at approx. 30″L x 36″W (76 x 91 cm).
Incline
This ProForm treadmill features an automatic incline system. In other words it uses a motorized lift to add incline to the deck, motor controlled from the machine’s console. Needless to say, the lift is situated under the front part of the deck, near the belt motor. It provides a maximum incline of 10%, which can be adjusted in increments of 1%. There are gradual and quick incline adjustment keys on the console.
The running surface of this machine stands at approx. 6.5″ (16.5 cm) above floor level at 0% incline. At 10% incline, the front part will raise by a few inches, but basically you’ll be situated on the deck at the middle, not all the way at the front. Differently put, the overall elevation that you will get by running at maximum incline should be approx. 15″. So, in conclusion here, the ceiling height in the room where the treadmill will be in use should be higher than your own height, plus 15″ (38 cm).
Motor
The ProForm 520 ZN treadmill uses two motors, one to set the tread belt in motion, the other for incline. Therefore, it requires to be connected to a nominal 120-volt circuit. It doesn’t have an adapter, but a normal 3-prong plug, U.S. standard. It’s recommended though to use a surge suppressor, in order to avoid any damage to the electrical components of the machine in case of surge.
When it comes to the motor that powers the belt, this treadmill uses a 2.5 CHP Mach Z model, built to perform well for long duration workouts, without choking or overheating, even if the user is close to the maximum supported weight. It supplies speeds up to 10 MPH. Speed can be adjusted in increments of 0.1 and 0.5, which gives you the possibility to find the pace that fits best to you.
Console
As opposed to the console on the ZT6 model, this unit uses a smaller display, 6″L x 2″W. However, the values are displayed in pretty large digits, easy to read. 
It indicates time, speed and incline settings, distance, pulse and calories burned. Also, for distance there is a race track function which displays a 1/4 miles track, indicating your progress on the current lap, and the total number of laps completed.
There are 18 pre-set programs on the console, split in 4 categories: Speed, Incline, Calorie and Intensity. The console doesn’t offer the possibility to create your own programs. There are no “user profile” settings. Also, the console is not telemetry enabled. In other words it can only read pulse through the EKG sensors on the handlebars of the machine.
On the other hand, the console integrates several amenities. These are tablet holder, sound system and fan. The fan is situated between the gradual and direct adjustment key sets. It’s not an extremely powerful fan, but still, it does provide some cooling. It has several speed settings, the keys for it being situated at the top-right part of the console. The top part of the fan plastic cover doubles as a tablet or book holder.
The sound system isn’t the best out there, but still, it’s much better than the sound provided by the speakers of a tablet or phone. It’s compatible with most MP3 players, phones or tablets, including iOs and Android devices. It’s a feature great to have as it offers the possibility to keep your music close as you run, but without having to use earplugs, which may be inconvenient during workouts.
Finally, the console unit of this running machine is fairly easy to operate. As we’ve mentioned above, it features keys for quick and gradual adjustment for speed and incline. Each program category has its own button, while the lower part of the console features two Start/Stop buttons for pausing and resuming your workout if it’s the case. These are excellent if you want to use the Manual running mode of the treadmill, alternating with various other forms of exercise.
Assembly and Maintenance
The complete assembly of this machine shouldn’t take more than 2 hours, and the most difficult part is transporting it to the place where it will be in use, as it’s a heavy item. Evidently it requires at least two people. The assembly itself is straightforward, and you’ll also have the manual which will guide you through it. Hex keys for assembly are included, but certain screws will require your own Phillips screwdriver. Overall, the assembly requires you to attach the console mast, and the console, connecting the wires. The deck comes fully assembled with the motors already integrated.
Just as any treadmill, the maintenance of this particular model requires the periodic cleaning of the running belt, and vaccuming under it. Any objects that can be caught in the motor or within the rollers should be removed. The belt itself is pre-lubricated with industrial lubricants, and it shouldn’t need additional lubrication for a long period of time.
The Pros
- Sturdy frame construction;
- Solid deck, being able to support users up to 300 lbs;
- Folding frame, space-saving design;
- 2-cell (on each side) deck cushioning;
- Motorized incline, 0% – 10%;
- 2.5 CHP motor, speeds up to 10 MPH;
- Speed can be adjusted increments of 0.1 MPH, allowing you to find the perfect pace for your workout;
- EGK pulse sensors integrated in handlebars;
- 18 preset workout programs;
- Various amenities such as sound system, multiple speed fan, tablet shelf, accessory trays;
- Quiet operation;
- Fairly easy to assemble;
- Little maintenance required;
- Excellent warranty.
The Cons
- Console not telemetry enabled;
- Fan not very powerful;
- No custom user programs.
Summary
The ProForm 520 ZN treadmill offers quite a bit more than a basic treadmill designed for running workouts. It’s actually an entry level running treadmill, great for anyone who wants to undertake cardio, interval and weight loss workouts, running a couple of miles per day. However, it may not be the best choice for a professional long distance runner, as its maximum speed is only 10 MPH. It’s a machine with a solid construction, an excellent choice for home use as it has a folding design, offering great value for the price.