DHT22 problem

Running a PICO V1.87
This code

//DHT22.js
//10Oct2016

var dpin=B3;
var F;
var H;

var dht = require("DHT22").connect(dpin);

setInterval(function () {
//  dht.read(function (a) {});
  dht.read(function (a) {
 F=(a.temp+40)*9/5-40;
 H=a.rh;
  console.log("Temp is "+F.toString()+" and RH is "+H.toString());
});
}, 1000);

produces the following output

>echo(0);
=undefined
Temp is 30.2 and RH is -1
Temp is 30.2 and RH is -1
Temp is 30.2 and RH is -1
Temp is 30.2 and RH is -1
Temp is 71.6 and RH is 52
Temp is 30.2 and RH is -1
Temp is 30.2 and RH is -1
Temp is 30.2 and RH is -1
Temp is 71.6 and RH is 51.6
Temp is 30.2 and RH is -1
Temp is 71.78 and RH is 51.6
Temp is 30.2 and RH is -1
Temp is 71.78 and RH is 51.6
>clearInterval();
=undefined

But this code

//DHT22.js
//10Oct2016

var dpin=B3;
var F;
var H;

var dht = require("DHT22").connect(dpin);

setInterval(function () {
  dht.read(function (a) {});
  dht.read(function (a) {
 F=(a.temp+40)*9/5-40;
 H=a.rh;
  console.log("Temp is "+F.toString()+" and RH is "+H.toString());
});
}, 1000);

Produces this output

>echo(0);
=undefined
Temp is 71.78 and RH is 51.6
Temp is 71.96 and RH is 51.7
Temp is 71.78 and RH is 51.6
Temp is 71.78 and RH is 51.6
Temp is 71.78 and RH is 51.6
Temp is 71.78 and RH is 51.6
Temp is 71.78 and RH is 51.6
Temp is 71.6 and RH is 51.5
Temp is 71.78 and RH is 51.6
Temp is 71.78 and RH is 51.8
Temp is 71.78 and RH is 51.8
>clearInterval();
=undefined
> 

Is there something missing in the module code?
Pin initialization?
A bit?