Stdout maxBuffer length exceeded- replace with spawn?

I have the following block of code

> reasoner = new Reasoner({
> 	type: 'local', 
> 	folder: 'csp_files' 
> });
> 
> console.log("solving Model");
> reasoner.solve(Model, (err, stdout, stderr, isSatisfiable) => {
> 	console.log("isSatisfiable");
> 	console.log(isSatisfiable);
> 	if (err) {
> 		// manage error
> 		console.log("model error");
> 		future_response.return("model error");
> 	} else {
> 		// manage solution
> 		console.log(stdout);
> 		console.log(isSatisfiable);
> 		future_response.return(stdout);
> 	}
> });
> console.log("Model solved");
> return future_response.wait();

I take the error attached here saying
...stdout maxBuffer length exceeded..

Obviously the error comes from the last future_response.wait()
How can I fix it please?
I have tried this command but didn’t help at all…
reasoner.solve(usCspModel, {maxBuffer : 500 * 1024}, (err, stdout, stderr, isSatisfiable) =>

Also the code is written from a npm library https://www.npmjs.com/package/governify-csp-tools if it is of some help…, previously with smaller data I could get an answer not that the file has lots more data seems that I have this problem…
A possible solution could be to use the library spawn, but how can the aforementioned block be rewritten using this?