Hi we have a problem that is driving us mad please can anyone advise!
We had 3 toilets 2 upstairs 1 down and all 3 are constantly running water. Our water pressure is very low so water company says it is low because the toilets are running and we need a plumber to fix all the toilets!
Now at this point I'm not convinced as firstly why would all 3 toilets have an issue at same time also if this was the case it wouldn't have happened intermittent previously and now constant for over a month? We have tried turning water off under our sink everlasting times whilst running the taps to let any air out (advice from water company) but nothing changes.

For now don't worry about the why, but focus on fixing the constant toilets running situation. Hopefully that's your problem, though I suspect you have blocked lines or cartridges also. Would help with knowing what kind of valves and floats in your toilets, because I have seen hard water build up/deposits wreck havoc with water pressure.

One way to dig down on this problem is turn off all the water supply to the toilets, and break the cold water line under a sink to see if you have full pressure before your sink fixtures. Make sure your house water valve is fully open as well as any shut off valves.

A good handyman or plumber can guide you through this and determine what the real root cause is. It may be as simple as things went unnoticed because it was happening slowly until it finally reached failure point. Sounds like you have called your water supplier as major leaks in the system will certainly ave everyone not just you without good water pressure. Talk with your neighbors!

These links may help,

https://www.angieslist.com/articles/...e-my-house.htm

Leaking Toilet or Low Pressure | Pawtucket Water Supply Board

4 Ways to Troubleshoot Low Water Pressure - wikiHow

Check water pressure first. Pressure should not exceed 55 psi. If higher than 55psi - reduce pressure down to about 45-50 psi

Second, lift lid and look inside tank. See if water overflows over the top of the overflow tube. Water level should be about 1/2" below the top of the overflow tube. If water overflows - replace Fill Valve

Thirdly, if water level is below the overflow tube and water still runs, look in side the toilet bowl and see if you can notice running water. Here, look closely. It may be hard to see clean water slowly running on white porcelain surface. We sometimes even use food coloring liquid to see it running ( we put few droplets of food coloring into toilet tank and watch for leaks inside the toilet bowl ). If water runs from tank inside the bowl - replace flopper

Hope that helps

Milo

Is water running into all 3 toilets steadily (hard to imagine) or is it a relatively slow leak in each toilet that results in water running occasionally into each toilet for a few seconds (more likely)?

This might help you out.
https://www.youtube.com/watch?v=G25lcYXaWCM

The water company is blowing smoke at you, a running toilet does not lower your pressure any more than turning on a faucet. When the tank is running do you see the water level reaching the top of the overflow tube inside the tank? This could also be a bad flapper or flapper seat. Both of which can be changed for about $20 if you do the work yourself. I would not call a plumber or handyman until you have a better idea of which is your issue. They charge by the hour so why lrt them be a paid detective

The water company is blowing smoke at you, a running toilet does not lower your pressure any more than turning on a faucet. When the tank is running do you see the water level reaching the top of the overflow tube inside the tank? This could also be a bad flapper or flapper seat. Both of which can be changed for about $20 if you do the work yourself. I would not call a plumber or handyman until you have a better idea of which is your issue. They charge by the hour so why lrt them be a paid detective