AIR HANDLING UNIT

[Greengo1990]

Anyone know why air handling unit may be tripping? Motor runs fine but after a couple
Of days it will trip out? AHU has a heating coil which seems fine.

 

[MDJ]

what does the controller which runs the unit say? my experience with them tells me it could be several things. the filters could be dirty so the air flow low, that could trip it, if it has belts they could be too tight or too slack. The motor may have a very slight earth leak, is there a frost stat on the unit to protect the coil? if so it may not be set properly. The actual main coil may need a good clean, it could also be very dry and need some condence sprayed onto it, the main grill from the extract may be dirty and again the air flow may be low, plenty of reasons to be honest.

 

[Pete999]

What he said plus how is the motor started DOL SD etc over loads set too fine.

 

[Deleted member 72666]

As Mike said, it could me many things. When you say 'tripping out' does the motor's overload unit trip out or is it the panel showing a fault eg low air flow, temperature out of limits etc?

 

[Pete999]

More information required really Mate could be anything, any testing done etc. Any one mentioned blocked filters oh yeah MJD did in his answer.

 

[Marvo]

You mention the motor and the heating coils. What exactly is tripping?

 

[Toneyz]

What is tripping?

 

[Pete999]

What is tripping?

Post 1 says the motor, at least that's my read

 

[ipf]

Better get an air con 'engineer' involved with some SY cable.......they'd probably know from the info given.
Proper electricians know nowt about 'em........

Mind you, the OP could well be one.

 

[Pete999]

If the Motor, motor wiring has been tested and no faults were discovered, it could well be down to the thermister installed during the motor's construction sensing unit gone ----- up. Al the large AHUs I worked on had this design, as do lots of medium to large, squirrel cage motors, dirty filters both primary and secondary filters in the AHU could be the cause, are there any records of filter changes? damaged belts could also be the isssue, before you go removing expensive motors etc I would certainly investigate these points of failure. Loose or damaged belts can be easily be heard by a squealing sound during start up, a poor airflow could be the indication as well, along with blocked / damaged filters. Is there a general maintenance regime in place, or is it a case of it works leave it until it breaks down.

 

[MDJ]

Another Numpty OP who asks a question and then Disappears, I'm done with this Dick.

 

[Spoon]

Another Numpty OP who asks a question and then Disappears, I'm done with this Dick.

And it's usually me who scare the OP's away and I've said bugger all....

 

[telectrix]

And it's usually me who scare the OP's away and I've said bugger all....

well that's a first.