Installing a new combination boiler seems to have caused my washing machine to break?

Well, it is indeed possible, it has happened to me twice. But it has nothing to do with the pressure, it has been the temperature. Having a combination (or tankless coil as we call them on this side of the pond) boiler will allow you to have domestic hot water leaving the spigot at over 160 degrees (71 C), hot enough to cause serious burns.

And apparently hot enough to damage the fill valve or solenoid in my washing machine. I've not tried to repair one yet so I can't say for sure what is getting damaged. I do know when I had a separate hot water heater there was no problem and washing machines would wear out normally after a long life.

A "tempering" or mixing valve should have been installed on the domestic water output and properly adjusted. You could always measure the temperature coming from the hot water spigot that feeds the washer just to check. Normally hot water should be around 125 degrees (51 C) at most, some households with small children leave it lower.

Hope this helps.

If you have any check valves or a water meter fitted this can have an effect of increased pressure when the hot tap is run & then turned off. The trouble being that the water is still expanding when the tap is turned off.

Fit an expansion vessel in the incoming cold water supply to the boiler (the stainless steel variety)

The Benchmark Log book always say that 'has the boiler been fitted in accordance with these instructions' and needs a tick beside it to verify a yes or no

Its very possible that the new boiler could have caused the valves to go, as for predicting it, that not really possible, its just down to bad luck. The valves are not that expensive so the repair bill shouldn't be that bad, but one thing you should do is reduce the water pressure to the washing machine and dishwasher if you have one fitted, to do this you will find taps at the end of the fill hose's where it joins onto you plumbing as combi boiler work on mains pressure, turn the lever taps to half their open positions and turn the washer on and listen to to see that the machine is filling OK.

I doubt that your combi boiler has caused this problem most washing machines will work quite well with water pressures in excess of you combi boiler pressure, you are just a victim of technology, if its made by man its gonna break sooner or later, and by the way if anyone tells you to reduce the pressure by half closing the supply valves all this will do is change the flow rate not the pressure.

Changing the boiler will not change the pressure. Your water pressure is always determined by the feed line of the utility. Valves go bad all the time and I seriously doubt the new boiler had anything to do with that.

That is a ridiculous suggestion. Thousands of people have washing machines and combi boilers working quite well. Someone is pulling the wool over your eyes.

A modern washing is designed to accept mains pressure on both its filling valves... Your plumber could not have anticipated this......Replacing the valves is not a big problem.

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I have a new combination boiler and I am sorry to say that it has caused nothing but problem good luck mate!!!!!!!!!!!!!!

maybe it was just coincidence?