Michael Symonds complained to Knighton's town council and asked them to seek a resolution for the sake of everyone affected.
F M Caine and Sons, a fallen stock collection company which has been blamed for the smells, said there are still things that can be done to reduce the effects.
Mr Symonds said: “The prevailing wind blows down the valley from the abattoir towards the town. In hot weather even the slightest breeze carries the aroma with it. The smell can be so strong that being outside is unpleasant and staying indoors means that one cannot open the windows.
“In fairness to Caine’s the situation was addressed a couple of years ago but the recent hot weather has brought it back to previous levels. I know that I am not alone in airing this concern.”
Town Councillor Ben Caine, the managing director at F M Caine and Sons, said the weather has been quite extreme in recent weeks.
He said the business has installed another deodoriser at the front of the site.
“I don’t think all the smells in the town are from us. But we are working with dead animals and it does smell.
“We are not doing anything different than what we have for years. I am trying my best to get it sorted.”
Councillor Caine said the business is looking at creating an enclosure for bins and lorries at the bottom of the site.
“There are still a few more things we can do but we have got two deodorisers in each building now.”
Some councillors reported strong smells from a lorry going through the town between 7am and 9am.
Councillor Caine said the large lorries should be leaving between 4am and 6am, so he would make enquiries about that. He said other companies’ lorries also come through town regularly.
F M Caine & Sons was established by Michael Caine, just after World War I.
The family business has been based in Knighton, Powys since 1956.