Another fried relay connection

Hi Mike
I've pinched someone else's photo - the melted area on my cust's was the bit in the red rectangle. I reconnected the burned out wire and got mains at the lower immersion (18 Ohms) so joy for now but I want o replace the appropriate parts.
I see you say there's an upgrade part - can you give us the part number?
Should I be replacing both relays?

In this marvellous installation there's no timer at all, though it has the two electrical supplies.
The "daily boost" black button did nothing at all. Would that be because it "thought" the lower element was on?



(Chris from gasnews)

Without a timer or an off peak circuit the bottom element will come on whenever the thermostat calls for heat and the boost does nothing. If you introduce a timer so the off peak terminals have a retricted supply that is only live whilst the electricity boards meter is recording units at off peak rates i.e. cheap rate. For Economy7 this is 00.00-07.00. When the off peak is dead and the meter is recording day rate (Peak) then the boost button will switch on the upper element via the r/h relay. Should save a bit on the electric bill. Also ask electric board for Economy 10 the off peak hrs are 00.00-05.00 then 13.00-16.00 then 20.00-22.00 much better for topping up the temp of tthe water. Good luck.

Hmm thanks, that's about as I thought. But I'm the plumber, customer is the landlord and the hapless user is the tenant, so the less they understand the less they'll worry, "unfortunately".
I was looking for a bit of experienced guidance on which parts to change, sometimes the tech lines are reluctant to admit that their products have such things as common faults

OK you only have to change the left hand relay and base, the r/h one is for boost only. Why not swap them round. RS keep thaes items, 329991 (relay)£20.34. 376105 (relay base) £22.47 Or call Gledhill and they will post them to you. I have seen a din rail mounted 25A contactor (like a Wylex MESB24 £31.60 from www.tlc-direct.co.uk) to get over the burning of the tag connectors, best speak to an electrical wholesaler for that.

Got a similar problem and forgive my 1st time post . Left hand relay has melted and looks like it has taken out the PCB and part of the wiring harness . Its in a block of retirement apartments and surprised it did not set off the smoke alarms . Been on the Segel website and looks like once the PCB , relay and base are priced up along with the recommended contact relays going to be very expensive .

[code]
[code]

Sorry hopefully pictures will explain in better detail !!!

I used a new base from RS or Farnell or similar - much cheaper than Gledhill, and as suggested above, swapped the other relay over.
The wiring they use is poor, it obviously suffers when it gets hot.
Is that PCB actually damaged, or is it just soot which would clean off? It's not exactly a dainty board, so it would probably take some scrubbing to get it clean.
Good luck!

ALso I didn't have crimp terminals with me when I replaced the base, so the damaged wires had to be cut back and the bare ends just put under the base's screw terminals. So far it's OK - a few months now!

Hi Chris
Thanks for the replies. Will make arrangements to swap the relays over . Pulsacoil still works on boost so at this stage will assume the PCB is intact although there has been some swelling to the component immediately to the left of the one marked " Omron" . Most of the soot should clean off however the 2 melted brown wires are more of an issue as they terminate into the push in plugs on the board so I have to either replace that section of wiring ( if it is available as a spare) OR Cut out the bad section and rejoin .

John( Dorset )

Hi John,

If you purchase the retrofit relay kit it will come with the new wiring you describe aswell.

Kind regards

Gary

MK Group Limited

A replacement relay and base have been order from RS but until they arrive have just switched the relay and base over . The left hand relay (Off Peak )and base was so badly fried so only good for the bin . To sum up the wiring for the right hand relay has been insulated in PVC tape during the switch with no relay in the right hand position.
The strange thing is with the off peak relay fried , customer last night said he still had hot water from the boost function (right relay ) which seem to make sense but this morning it was completely dead .Not much more I can do until the relay arrives unless there some other tests I can do .

Just a quick update . Sent the pictures to Gledhill and got a return call from promptly.They have advised me to replace both the PCB and relays.
Going to be quite an expensive repair considering the Pulsacoil is just over 3 years old .

"they would say that wouldn't they"
If there's signs of damage to the components I huess you have no choice unless you can solder replacements in.
I'd change the relay/holder and see if it actually works - what do you have to lose? I don't know if you're the owner of this thing - if not, give the customer the choice?

Agreed Chris ,
The relay and holder are coming from RS and with a bit of luck will be with me 1st thing next week . I'm not the owner but was called in to look at this although have to say its the first one I have looked at .Thanks again .

Hi Just seen your photos, this is pretty bad overheating.
Just to add, this ACB (appliance control board) is not the best, if it is working leave it alone, Gledhill are experiancing reliability problems with the replacement ACB's they are selling. this is mainly error code 29. I have even had a couple allow overheat situations to occour.
The photos look bad, but the components affected relate to the heat exchanger pump connection in the bottom right hand corner, however there are surface mounted componants on the back which maybe fried.
If I were you, I would ask a local electronics engineering company to repair it. There maybe someone local online, or an exchange via a ebay store.
good luck
Paul Brown.

Thanks Paul
So assuming the ACB is only damaged around the pump control area the immersion heaters should still operate once the relay has been replaced.
On this basis it would work but with a very erratic temperature fluctuation at the HW draw off points . The part number quoted by Gledhill for the ACB was XB103 with no mention of the reliabilty problems - just typical !!!

Relay arrived from RS this morning and fitted this afternoon . Board reads no error codes but only seems to work on boost function ONLY. If I switch off the boost board readout says S6 calling for heat but no power to top immersion heater . Just found another fault - immersion heater leaking from where the stat would normally go on standard immersion heater .