They were also instructed to give her $6000 in compensation.
ERA member Dzintra King wrote in her determination that the sacking was "unjustified."
The ERA was told Ms Faulkner was hired to run the groom school in January this year.
She was running grooming courses and worked 55 hours per week, for $14 per hour.
But on April 13, Tielcey Park Equestrian Centre manager Damon Forde told her she was suspended on full pay and was to "pack her belongings and leave the property within one hour".
Ms King stated in her determination: "Ms Faulkner asked what she had done wrong. Mr Forde refused to tell her but said he would let her know by letter with (sic) 72 hours."
During the ERA hearing, Mr Forde claimed to have sent Ms Faulkner two letters - one saying he was conducting an investigation, and the second to say he was "satisfied" that he was terminating for employment on April 13 for "serious misconduct."
However, the ERA had "no hesitation in finding that these letters were never sent" to Ms Faulkner.
Ms King also heard evidence that Mr Forde had approached Ms Faulkner and "screamed and yelled at her".
The authority was also presented with a medical certificate that detailed the effects of the dismissal on her.
The ERA concluded that Clarity Group Limited was to pay Ms Faulkner $10,010 in 13 weeks' wages and $6,000 in compensation.
Last night, Mr Forde refused to comment, saying that Clarity Group Limited was appealing the decision.
Justified dismissal
Meanwhile, the ERA has also found that Vodafone was within its rights to sack an employee for sending inappropriate emails from a work address to staff and friends, including comments she was not really sick but going home to go to the toilet.
The ERA ruled Vodafone New Zealand was within its rights to fire Papataia Toleafoa from her call centre customer service representative role in February, and declined her personal grievance application.
The telecommunications company began monitoring Ms Toleafoa when she sent out an email to 200 employees on January 18 asking if anyone wanted to join the union and referred to upcoming salary reviews.
She was warned to not use her work email for personal use, and told management she would not do it again.
Following the warning, Ms Toleafoa sent emails to friends from her work address that included derogatory remarks and said she was going home early for false reasons over the course of January 20 -25.
"I'm off home, coz I've told my pule that I'm going home coz I'm stressed. Aoooo, fia ki'o more like it,'' she wrote in one email.
The authority translated the word "pule'' to mean boss and phrase "fia ki'o'' as meaning "going for a s***''.
Ms Toleafoa took sick leave on six days between January 24 and 31 claiming she was stressed, the report said.
Emails over this period also called fellow staff "ufa's'' and "kefe's'', Samoan words for "d***head'' and "f***wit'', and said a staff member "talks like a cow chewing on grass''.
Ms Toleafoa was also seen to ignore an incoming business call and instead talk on her personal cellphone on January 21, which she agreed she shouldn't have done.
ERA Member Robin Arthur ruled the language used in the offending emails justified VNZL's finding of misconduct.
A Vodafone spokesperson said today that the company was confident in its decision, and was pleased it was supported by the ERA.
He said the company hasn't had to issue a collective warning to all staff about the correct use of work email, but the ERA decision does '' reinforce our clear messages about what acceptable behaviour looks like.
While Vodafone doesn't actively monitor employee email usage, it reserved the right to do so if there were indicators of inappropriate usage, he said.
