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Although a CSV will work with any size pressure tank, larger pressure tanks are no longer needed. With a CSV, a 4.4 gallon size tank, which holds 1 gallon of water, is sufficient for any size house. Larger pressure tanks are simply a waste of money and space.

A Cycle Stop Valve (CSV), as the name implies, stops pumps from cycling. When water is being used, the pressure tank drains and the pressure switch starts the pump. The CSV then varies the flow from the pump to match the amount being used. Water flows past the pressure tank, directly to the faucet, at a constant 50 PSI. Only when all the faucets have been turned off, will the CSV allow 1 GPM to slowly fill the pressure tank to 60 PSI, and the pressure switch shuts off the pump.

Ideally, at least the information about the issues associated with high pressure would be provided to you by those responsible for supplying you with water as a public service announcement; as the problem of high water pressure in homes it is not a widely known issue.  It could be part of water saving measures and perhaps a scheme could be implemented to test and install PRVs on people homes at a reduced cost so that water is not wasted (through slow or fast leaks).  The fact that this hasn't happened probably indicates the incentives aren't there to do it.  Until such as scheme is implemented it is up to the homeowner (and their plumber) to protect themselves from high water pressure.

It is also probably better to buy (or borrow) your own meter as you want to get readings at various times of the day; as previously stated water pressure changes throughout the day and tends to rise at night.

The maximum number of cycles allowed for a 1 HP pump to survive is 100 times per day. The average person in the US uses 75 gallons per day. Just one or two people in the house can use enough water to cycle the pump many times per day. Add a sprinkler, an open loop heat pump, or just a few kids, and that can easily cause more than 100 cycles per day. Larger pressure tanks reduce the number of cycles, but they don't stop cycling.

Almost 2/3s or more of a tanks volume is filled with compressed air, it takes a very large tank to hold 10 to 40 gallons of water. The higher the pressure switch setting, the less water volume a tank can store.

All of which probably adds up to more than the $400 you would spend installing a pressure reduction valve at the inlet to your home.

Water is provided to you via a very simple principle and that is, water runs down hill.  Water is stored in a high place (i.e. a reservoir) and is distributed to your home which is in a lower place.  The maximum water pressure you could receive fundamentally depends on the difference in height between your house and the reservoir, in the same way that something rolling down a hill gains more speed if it starts higher up the hill.

Cycling causes the premature destruction of pumps, motors, pressure switches, relays, capacitors, check valves, and even the pressure tank. Cycling causes water hammer which pounds on faucets, seals, washers, appliances, pipe, and pipe-fittings. Cycling the pump can cause the house lights to flicker and annoying swings in shower pressure. Cycling can cause pump wire chaffing, pumps coming unscrewed, noise, and high electric bills. Even problems with minimum flow for tankless water heaters can be attributed to cycling.

The Australian standard covering water pressure in the home (AS 3500.1:2018) mandates that water pressure in a building must be kept below 500 kPa (unless the outlet is used for fire fighting), where a building is defined as a structure, temporary building, temporary structure and any part of a building structure in the Building Act 1993. The reason for this requirement is that water pressure above 500 kPa has the potential to damage valves, tap fittings, flexible hose fitting etc as the components are only rated to withstand pressures at or below 500 kPa.  So if your pressure is over this level you probably want to get a pressure reduction valve (PRV) fitted.

Water pressure that is too high is an issue that can affect your home; it is the intent of this article to arm the reader with the information to understand the issues around high water pressure so that they can do something to mitigate its effects.

To have a PRV fitted you can expect to pay between $300-$425 depending on where you are (according to online service pricing sites), which is not exactly cheap but if you stack that up against the cost of not installing a regulator it will work out cheaper.

A pressure tank supplies water as the pressure drops from 60 to 40 PSI. At 40 PSI the pressure switch starts the pump, the pump fills the pressure tank to 60 PSI, and the pressure switch shuts off the pump. This is called a cycle. Cycling the pump on and off causes almost every problem with pump systems.

The following charts show the drawdown of tanks from 2 to 119 gallon actual size, with 40/60 compared to 60/80 pressure switch settings.

In the past, pressure tanks were sized to store at least 1 or 2 gallons of water for every gallon per minute the pump can produce. A 10 GPM pump needed a pressure tank that holds 10 or 20 gallons. A 20 GPM pump needs a tank with 20 to 40 gallons of storage.

Water pressure is not uniform throughout a given water distribution network it will depend on a number of factors such as:

It is important to note that keeping pressure in spec for outlets in the home is the responsibility of the homeowner (and their plumber), your water supply company does not have jurisdiction past the water inlet to your home (like many other industries of society the water supply industry is siloed).

Ok, that is mains water pressure but what about water pressure in your home.  If the water pressure is too high you can decrease it with a pressure reduction valve (PRV) at the water inlet to your home or increase it with a pump if it is too low (a much rarer situation).  You can measure the water pressure using a $20 water pressure meter from Bunnings (the cheap option) or you can have a plumber come over and measure it for you (not recommended).