Re: Sealed instead of vented heating system

So do you think the pump is set too high and that has caused the problem? The pump is new, the old one died a death in the Spring. I honestly don't know what to think, but why won't a sealed system solve all the problems? What could go wrong with moving to that? We have had no end of problems with the vented system. It's not just one company that's tried to fix it.

Re: Sealed instead of vented heating system

So is it possible that the owner sabotaged the system by setting the pump too high?

The low pressure error message came from the boiler itself.

Re: Sealed instead of vented heating system

That I must admit I don't understand

To the best of my Knowledge only low pressure warnings are on sealed combi boilers not on normal vented systems.

Re: Sealed instead of vented heating system

Agreed. Annie, can you tell us the precise model number of your boiler and also tell us what error code is flashing up?

Wish I lived close, then I'd come over and temporarily make your system a closed pressurised one (bypassing the plastic expansion tank in the loft by replacing with a pressurised expansion tank (with integral pressure gauge) and filling loop) to see if this would work.

This is pretty much what would need to be done anyway, but the positioning of all of this would have to be somewhere closer to the boiler at ground and deadleg pipework removed/isolated for reasons which I can't be bothered to explain at present.

Re: Sealed instead of vented heating system

Hi, one fault code was F23 and another was F28. I was told one of those codes may have come up when the gas was turned off temporarily. The other was a low pressure fault. It's a vailant ecotec plus 428.

Re: Sealed instead of vented heating system

F23: Could be the new pump isn't powerful enough

https://ephg.limited/vaillant-boiler...ault-code.html

Re: Sealed instead of vented heating system

I have read a magnaclean should be installed before the powerflush. Is that right?

Re: Sealed instead of vented heating system

Doesn't really make any difference whether it goes in before or after. However, as a flush will be sending gunk through the system, if you install before, you'll have to clean out the magna.. Only a 5 mins job - turnt the isolator valves off, unscrew the lid, take our the gubbins and rinse off. Not special skills required - if you can open a jar, you can service a magna.

Re: Sealed instead of vented heating system

Annie - if you have easy access to the pump, adjust the setting to a higher one.

Re: Sealed instead of vented heating system

Or gas pressure too low

F.28 : Appliance does not start: Attempts to ignite during start failed

Faults in the gas supply such as:- - Gas meter or gas pressure detector defective - Air in gas- Gas flow pressure too low - Fire protection tap has disengaged Faults in the gas valve, wrong gas setting, igniter (ignition transformer, ignition cable, ignition plug) defective, ionisation current stopped (cable, electrode), faulty earthing in appliance, electronics defective

https://ephg.limited/vaillant-boiler...ault-code.html

Pay particular attention to the question about diy fixes