Warmflow Oil Burner E48 code

[conny]

As above, we have a fault code of E48. Looking on line it says pressure to high and to consult an engineer.
Everything has been working fine so what can cause this and is there anything I can do to rectify it?
Engineer can't come until tomorrow.

 

[oilhead]

Drain off some water to lower the pressure. Have you topped the pressure up recently?
Which model Warmflow is this?

 

[conny]

Not sure what model it is as there are no visible labels other than the Warmflow badge on the front.
We had no hot water this morning and had an EO4 code. Looked it up and it said low pressure. So I very slightly opened the loop valve just a fraction, because we couldn't find the gauge, for about 5 seconds then closed it tight. (One of those stupid screw type in the pipe rather than a flip handle, as I call them). My wife pressed the start button and it fired up. Everything has been fine during the day until my son went for a shower mid afternoon and said the water was cold. Looked at the code and it said E48, then I lifted the lid and seen the gauge. Black needle was on about 2 3/4 and the red needle was at 4.
I did think about draining a bit out of one of the radiators but thought it best to leave alone. Boiler is less than 12 months old.
Engineer has now agreed to come at 8.00am in the morning so will leave it to him but curious as to why it would go from low to high when I only let a trickle in. If the old boiler lost pressure it used to take about 5 minutes with the loop half open. This took no more than 5 seconds with the loop just about cracked open to what I thought would be a tiny trickle. We used to have very good water pressure until they started building a new estate down the road, now it's about half the pressure it used to be.

 

[Exedon]

You have probably inadvertently left loop slightly open.
Remove the flexi loop to check.

 

[oilhead]

Do you have a tap at each end of the filling loop? If so make sure both are turned off. If it is a combi, as it would seem to be, then maybe Domestic heat exchanger is goosed.

 

[conny]

Do you have a tap at each end of the filling loop? If so make sure both are turned off. If it is a combi, as it would seem to be, then maybe Domestic heat exchanger is goosed.

Hope not! As I say, it's been in less than 12 months.

 

[Johntheo5]

Could be E.,vessel problem, PRV may be lifting at 3 bar, it will then only require a few seconds of refilling to restore the pressure to normal if no expansion space.

 

[conny]

All cleared and working. I opened the old loop fill which, apparently, by-passed the safety cut out on the new loop. He drained the pressure off back down to 1 bar and showed me how to use the new filling loop inside the boiler. He said they now have sensors for low and high pressure so if it goes either way the boiler simply won't function until it has been rectified. No explanation as to why it lost pressure except that they all do over a period of time, so you have to keep an eye on them and maintain them at 1 bar when cold.
Thanks for the replies guys.