Ecodan U4 error code
I've cleaned that solder joint up and resoldered it, looks good now. But today no matter what I've tried the machine will not spin up. I've tried wiggling the wires connectors, thermistors on the pipes but nothing! I'm all out of ideas.
I discovered that there are some dip switches (SW2) that can be set on the unit's controller board which will indicate the exact thermistor at fault. In my case it was the water inlet thermistor that was showing a wrong resistance which I missed when I was testing each thermistor for general operation not actual readings.
Part ordered and hopefully that will be it fixed!
@spacebiscuit could you detail what switches you changed maybe useful for someone else in the future thanks
On SW2 switches 1, 4 and 6 need to be on - this will then return a number corresponding to a thermistor. Although in my case it returned '3' which could be one of two. So I then had to try 3,4,5 on which gives the temperature of the inlet - mine was read '102' which is not achievable and so indicates a bad resistance reading and therefore TH32 being the faulty thermistor - I hope!
See pages 74 and 76 here:
Page 55 shows the resistance range for TH32, which could be measured if you have a suitable multimeter. You could also test the circuit board by connecting a suitable resistor in place of the thermistor.
Oh I didn't see that - so I'm getting 300-320 ohms on that thermistor....
- 22 Forums
- 2,097 Topics
- 46.2 K Posts
- 49 Online
- 3,385 Members
Join Us!
Latest Posts
-
RE: Mitsubishi cycling while on chilled water output
@downfield I think the cooling capacity ratings for you...
By IaAck , 34 minutes ago
-
RE: Weather compensated secondary circuits with Biomass
@sune thanks for the LK link, looks like a possible opt...
By AndyCoo , 14 hours ago
-
RE: Heat pump solutions and/or installer recommendations for France
No idea, but Google-Fu leads me to Bon chan...
By Scalextrix , 16 hours ago
-
If you are thinking of heating on the immersion conside...
By JamesPa , 1 day ago
-
RE: Surface mount or bury primaries for heat pump installation?
@tomasmcguinness, I think your best bet would be using ...
By Aventus Eco , 2 days ago
-
RE: Solar Power Output – Let’s Compare Generation Figures
@toodles all depends on asking the right questions! And...
By Tim441 , 2 days ago
-
RE: Commencing on an ASHP Installation Process
I received confirmation this morning that my Greener Ho...
By Sheriff Fatman , 2 days ago
-
@jamespa Thanks for the advice - very helpful. I had al...
By abam48 , 3 days ago
-
RE: Adding battery storage to SolarEdge PV system
@chandykris No need to apologise at all! I forgot to ad...
By Toodles , 4 days ago
-
RE: Say hello and introduce yourself
Yes please do Suggesting a loss in the region...
By JamesPa , 4 days ago
-
As I have reported elsewhere we turned on the cooling o...
By downfield , 5 days ago
-
-
@el3b Hi, sorry to hear that, it is advisable to instal...
By ASHP-BOBBA , 6 days ago