controller issue?

[pivotal]

Im not an engineer, the company who supplied & maintained the equipment for the previous owner just is not responding & I need solid advice.

Last week & multideck lost gas (again) & we had it taken away, the next day our 2x3m serve over counters frosted over. We cleared them & switched off for a full defrost & clean.

One now blows the circuit breaker, connecting to an isolated circuit it powers up but wont start the compressor, fan works, the compressor thumps every few seconds as it tries. I'm giving up on this one.

The other one works, in a way. It had been fine, running auto defrost etc, but now when it does a defrost it passes its endurance time & doesnt restart. Manual restart nothing, until I bring the setpoint up to the what ever the probe temp shows. I then drop the setpoint down to the value I want, & the system runs for ever - or until defrost/switch off.

The controller is a replacement unit - Eliwell ewpc961, the differential is set to 1, everything else has been tried at the defaults & various combinations. The data sheet show a differential range of +/- 15, I can only set 1 to 15.

Obviously my chilling capacity has been severely curtailed & while I seek local recomendations for a new engineer I would appreciate any advice on where the fault lies, I suspect the controller, which I could swap with the other dead chiller.

thanks

[multisync]

Im not an engineer, the company who supplied & maintained the equipment for the previous owner just is not responding & I need solid advice.

Last week & multideck lost gas (again) & we had it taken away, the next day our 2x3m serve over counters frosted over. We cleared them & switched off for a full defrost & clean.

One now blows the circuit breaker, connecting to an isolated circuit it powers up but wont start the compressor, fan works, the compressor thumps every few seconds as it tries. I'm giving up on this one.

The other one works, in a way. It had been fine, running auto defrost etc, but now when it does a defrost it passes its endurance time & doesnt restart. Manual restart nothing, until I bring the setpoint up to the what ever the probe temp shows. I then drop the setpoint down to the value I want, & the system runs for ever - or until defrost/switch off.

The controller is a replacement unit - Eliwell ewpc961, the differential is set to 1, everything else has been tried at the defaults & various combinations. The data sheet show a differential range of +/- 15, I can only set 1 to 15.

Obviously my chilling capacity has been severely curtailed & while I seek local recomendations for a new engineer I would appreciate any advice on where the fault lies, I suspect the controller, which I could swap with the other dead chiller.

thanks

The diff should be around 2 -4. It might be that the diff is too high and won't allow the unit to come back in.

Set it all back to std (except for the setpoint) and see what happens..Page 2

http://www.cascontrole.com.br/Contro...s/ewpc961s.pdf

Also where abouts are you BTW?

[pivotal]

The diff should be around 2 -4. It might be that the diff is too high and won't allow the unit to come back in.

Set it all back to std (except for the setpoint) and see what happens..Page 2


Also where abouts are you BTW?

I'm in the UK, just outside London.

Ive looked at the pdf, the parameters are not the same as my controller, my set just says 961 not /S

I've tried all parameters set to default, it makes not adifference, I tried the differential at 2 (default) up to 6, all the same result.

The panel has the indicator on for the compressor when its running or not, except when the defrost indicator is on.

[multisync]

I'm in the UK, just outside London.

Ive looked at the pdf, the parameters are not the same as my controller, my set just says 961 not /S

I've tried all parameters set to default, it makes not adifference, I tried the differential at 2 (default) up to 6, all the same result.

The panel has the indicator on for the compressor when its running or not, except when the defrost indicator is on.

If you can swap the controller then crack on. It will at least confirm if it is the problem but if the comp light is always on and the compressor isn't then it's looking more likely than not

However:

Diagnosing by forum is fraught with danger and most answers should be viewed as a guess based on the information available and not a absolute confirmation.

[pivotal]

If you can swap the controller then crack on. It will at least confirm if it is the problem but if the comp light is always on and the compressor isn't then it's looking more likely than not

However:

Diagnosing by forum is fraught with danger and most answers should be viewed as a guess based on the information available and not a absolute confirmation.

Ok,

I will try & work out the difference in connections (id 974) when I have had some sleep.

Pete

[multisync]

Ok,

I will try & work out the difference in connections (id 974) when I have had some sleep.

Pete

Make sure if they are both the same supply voltage -12v or 240v!!

Actuall I think one is a one probe and the other is a two probe. You will need to take a probe out too or it will just give a probe error..

[pivotal]

I will, thanks

[goshen]

hi before u start swapping controlers check this site out u might solve it easily
http://www.frostechnic.com/eliwell.htm

[pivotal]

The existing one is a 12VAC unit & the one in the 'dead' is a 240VAC, with a secondary relay.

I could mimic the wiring between the two, but a drop in replacement would be better, if I can identify the cost & a supplier.

[pivotal]

A quick update.

New controller installed (same part code, different parameter set)
& the system is work correctly now.

Thanks for the help

Pete