Worchester Bosch E9 Error - It's not the boiler !

[MichaelwGroves]

Mainly new radiators, so hopefully not corrosuion. Yep, all Hep2o is barrier.

All Radiators have TRV except Bathroom and Hall where Thermostat located.

 

[diamondgas]

5yrs !!!! 😀

12 radiators and 40kW of heat sounds a bit much too, by-the-way! Not that it should make that much difference as the boiler should modulate down to accommodate the changing environment!

I'm off to earn some pennie's ..!

 

[Howsie]

Call someone already.

 

[MichaelwGroves]

I've not been able to check flow and return temperature yet, but i was checking my diagram. It appears I have the supply and vent the wrong way round. Although, you could say my diagram had them the correct way round!
Please see updated diagram. The diagram now shows exactly the layout of pipes. I had to bleed my top radiator again and vent in front of pump. Could the pump be sucking air in from the main vent pipe?

 

[buckley plumb]

coukld you range rate the boiler down on the htg side to say 20kw for a while then see how it goes on . as above the pipe work may not take 40kw of heat.

 

[Roger Welton]

What buckley says, had a house that was sectioned off into flats each with there own combi's fitted with the exception of the ground floor which retained the existing boiler (40CDi) it was firing winding itself up then shutting off (up to temp) very quickly, dropped the max firing rate down (explained in the CDi engineers booklet off worcester site) and the job was a orange root vegtable

 

[stoker122]

The pump looks like it is pulling on the vent probably on start up.
It may be not pulling as hard just with hot water on due to higher resistance.
It could well be worth swapping the feed and expansion so the pump pulls on the cold feed instead.

 

[MichaelwGroves]

I'm thinking about lineing all my wet jobs up so I only need to drain system once.

Jobs so far;
Swap Feed & Expansion pipes. The Diagram now shows exact placement,is there a preferred point to tap off?
Replace 3 Port Valve for bigger. What would you recommend.

I'm thinking if I need to make the vent changes, should I consider converting to an un-vented system. Any benefits on one Vs the other?

I also have dry jobs, I will down rate the boiler and see how this goes, along with checking return temperature.

 

[Roger Welton]

I'd use 2 x 2 ports instead of a 3 port,

 

[diamondgas]

Is the vent before the pump automatic or manual? If auto that could be where you're drawing in air! Just a thought 😀

 

[MichaelwGroves]

Is the vent before the pump automatic or manual? If auto that could be where you're drawing in air! Just a thought 😀

Manual, thumb screw.

 

[MichaelwGroves]

Looked at this on Saturday, gave it a lot of thought. Clearly Vent is in wrong place and this muct be where airs is coming from, but this is just pushed to the Bathroom radiator where it coolects. It can't get to th boiler. So bad installation by origional plumber but can't be why boiler is erroring. Also 3 way valve, yep agree too small for boiler on max, but if this were the problem I would get problems with radiators not gettinmg not enough. So would be a good upgrade but probably not causing bolier to error. It would just act like sevetral TRV's backing off.

So last idea is down rate the boiler as it's heating up too quickly. Okay, the only time the boiler errors is on start up, once it gets going its fine. So I down rated central heating to 27kW.
Well since then it's been fine, no problems at all. I have left the hot water at 40kW. The radiators are not as hot as they were and the house is on the edge of just being warm enough, so I might tweek to 30kW at the weekend if it behaves itself.
So my advise to anyone who gets an E9 error is down rate it as your very first jobas it only takes 2 minutes.

Thanks for all the advice guys 🙂

 

[Roger Welton]

So it must be stuggling to flow the heat away as it ramps up the load on start up.

 

[MichaelwGroves]

That's a good way of looking at it, so if I removed the restriction by way of the 3 port valve, this might also solve it?

2 port valves was recommended, but to keep the job simple can I get a larger 3 way valve that will allow 40kW of flow ?

 

[Roger Welton]

I'd be looking at 2 ports, easier to wire and fault find, plus can flow more heat.

 

[MichaelwGroves]

What models would you recommend, all my pipe work is 22mm, so I would look to replace 3 way with 22mm T, striaght into 2 port valves ?

 

[Roger Welton]

Yup, I prefer honeywell valves personally.

 

[MichaelwGroves]

Would I get a full 22mm flow from Honeywell V4043, not sure on difference for "B" and "H". or would I need 28mm valve to get full flow?

 

[Roger Welton]

From Honeywell training manual

 

[MichaelwGroves]

That's mad, why does Worchester Bosch only come off the boiler in 22mm ?