Miraco 521 Grey High Pressure Valve 40-80 PSI
40-80 PSI
Miraco 521 Grey High Pressure Valve 40-80 PSI is backordered and will ship as soon as it is back in stock.
Features
Features
Warranty
Warranty
Delivery and Shipping
Delivery and Shipping
All products will ship according to shipping option selected at checkout. Standard USPS and UPS average shipping times are 2-7 and freight up to 2 weeks. Allow extra time during peak season and the holidays. For more information see our Shipping Policy.
Miraco 521 Grey High Pressure Valve 40-80 PSI
Description
Description
The Miraco 521 is the current grey high pressure valve for Miraco automatic waterers. It is rated for water pressure from 40 to 80 PSI and flows an average of 12.5 gallons per minute, so the trough refills quickly after a group comes to water.
It is a one for one replacement for the blue 521B, and for the older orange and red valves. The threads are the same, the pressure rating is the same and the flow is the same, so nothing else in the unit has to change.
The internal repair parts are not interchangeable. Grey valves take grey parts, blue valves take blue parts. If you are rebuilding rather than replacing, match the color of the valve in your hand, not the color the unit shipped with.
- 40 to 80 PSI
- Average 12.5 gallons per minute
- Direct replacement for the blue 521B and the older orange and red valves
- Comes complete and ready to install
- Rebuildable with the Miraco 521 grey valve internal parts repair kit
The valves swap. The parts inside them do not.
Miraco has used a few colors over the years. The oldest units came with an orange or red valve, those were replaced by the blue 521B, and the grey 521 is the current valve. All of them thread into the same place.
You are looking at the grey 521. It drops straight into a unit that came with a blue, orange or red valve. Nothing else has to change.
| Blue 521B | Grey 521 | |
|---|---|---|
| Pressure | 40 to 80 PSI | 40 to 80 PSI |
| Flow | Average 12.5 GPM | Average 12.5 GPM |
| Threads | Same | Same |
| Base | Two piece | Single, smaller, quicker to service |
| Replaces | Orange and red | Blue, orange and red |
| Repair kit | 521B kit | 521 grey kit |
This is where orders go wrong. The valves are interchangeable, the guts are not. Blue valves take blue parts and grey valves take grey parts. Match the color of the valve in your hand, not the color the unit shipped with.
The blue valve costs a little more than the grey. That is a manufacturing difference, not a performance difference.
The blue and grey valves side by side, and what is different inside them.
Why a Miraco 521 valve leaks
A valve that will not shut off is holding open for one of a handful of reasons. Work through them in this order.
1. Water pressure is too high
These valves are rated for 40 to 80 PSI, and this is the most common issue we see on city water systems. It shows up two ways. The valve can leak right away, or it can wear out early and start leaking later, because a valve running at the top of its range wears faster than one running in the middle.
Test the pressure at the unit, not at the source. Pressure builds up at the waterer, so a reading taken at the house or back at the well can look fine while the valve is seeing something much higher. Test several times through the day and take an average, since pressure moves with demand on the system.
Several waterers on one line is worth a look. A call we get often is that four or five units run fine and one keeps leaking for no reason anybody can see. That one unit is usually getting a buildup of pressure the others are not, and a pressure regulator at that unit is what solves it.
If you are over the range, put a brass pressure regulator in the waterline at the unit. We do not carry one for the Miraco units, so pick one up locally.
2. Debris is holding it open
Most common right after a new install or a line repair. If the line was not flushed, dirt, sand or a bit of rock travels down and lodges in the valve so it cannot seat. Flush new lines before you put a valve on them.
3. The valve is worn out
Parts wear and rubber gets tired. There is no set lifespan. Some customers run the same valve for thirty years and others replace one every couple of seasons, and water quality and pressure are usually the difference.
4. Deposits on the valve seat
Hard water leaves mineral deposits, and deposits on the seat keep the rubber from sealing. If the seat is pitted or the rubber has a groove worn into it, that part needs replacing.
5. It froze and cracked
Freezing can crack a valve, sometimes with a hairline you have to hunt for. If it started leaking after a hard freeze, replace it. That is not a repair.
6. The float is waterlogged
A float with a pinhole fills with water and gets heavy, and a heavy float cannot rise far enough to close the valve. Pick it up. If it sloshes or feels heavy, that is your problem.
If your car needs an oil change, you do not change the tires. When the valve leaks, the valve is what needs attention. Adjusting the float or swapping a good float for a new one does not change what is happening inside the valve. The only time the float is the cause is when the float itself is waterlogged, full of deposits or modified in some way.
Check it for debris
The valve is simple. No screen, no filter, nothing to lose track of.
- Shut the water off to the unit.
- Take the cover off the valve.
- Pull the plunger out.
- Look for debris in the valve and on the seat. A piece of grit is all it takes.
- Clean out what you find, look the rubber over, and reassemble.
If the rubber seat is cut or grooved, clearing the debris will not be enough on its own.
Repair or replace
If one part is worn, rebuild it with the kit that matches your valve color. Each kit has two valve pins, a plunger with valve seat, an upper arm and a lower arm.
If the parts are worn across the board, or the valve is simply old, put a new valve on it. Rebuilding a tired valve part by part costs you a second trip out to the pasture, and a complete valve comes ready to install.
Walking through a leaking 521 valve and what to check.
Common questions about the Miraco 521 valve
Is the grey 521 interchangeable with the blue 521B?
Is the grey 521 interchangeable with the blue 521B?
Yes, one for one. Same threads, same 40 to 80 PSI rating, and both flow an average of 12.5 gallons per minute. The grey also replaces the older orange and red valves.
Can I use blue valve parts in a grey valve?
Can I use blue valve parts in a grey valve?
No. The valves swap but the internal parts do not. Blue valves take blue parts and grey valves take grey parts. This is the most common ordering mistake we see, so check the color of the valve in front of you before you order.
Why does the blue valve cost more than the grey?
Why does the blue valve cost more than the grey?
The blue valve takes more to manufacture. It is not a performance difference. Both carry the same pressure rating and the same flow.
My waterer is overflowing. Should I replace the float?
My waterer is overflowing. Should I replace the float?
Almost certainly not. A leaking or running valve is a valve problem. The only time a float causes it is when the float is waterlogged, packed with deposits or modified. Pick the float up and check it. If it is light and dry, put it back and work on the valve.
What water pressure do these valves need?
What water pressure do these valves need?
Forty to eighty PSI. Test the pressure at the unit rather than at the source, because pressure builds up at the waterer and a reading at the house can look fine while the valve is seeing more. Test several times through the day and take an average. If your average sits at the top end of the range, the valve will wear down faster.
Four of my waterers are fine and one keeps leaking. Why?
Four of my waterers are fine and one keeps leaking. Why?
That one unit is probably getting a buildup of pressure the others are not. It is a common call when several waterers share one line. Test the pressure at that unit, and if it is running high, put a brass pressure regulator in the waterline there.
Can I clean debris out of the valve myself?
Can I clean debris out of the valve myself?
Yes. Shut the water off, take the cover off, pull the plunger and look. There is no screen or filter in these valves, so debris is easy to spot. Flushing a new waterline before you install a valve prevents most of these calls.
How long should a Miraco valve last?
How long should a Miraco valve last?
There is no set number. Some customers have run the same valve for thirty years and others replace one every couple of seasons. Water quality and pressure are what make the difference.
My valve leaked after a freeze. Can I repair it?
My valve leaked after a freeze. Can I repair it?
Replace it. Freezing can crack a valve, sometimes with a hairline that is hard to find, and a repair kit will not fix that.
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