Simple query fail

Hi so I have a simple table as

\d sensor_values_days;
Table "public.sensor_values_days"
Column | Type | Modifiers
-----------+--------------------------+------------------------------
ts | timestamp with time zone | not null
value | double precision | not null default 'NaN'::real
sensor_id | integer | not null
Indexes:
"timestamp_id_index" UNIQUE CONSTRAINT, btree (ts, sensor_id)
Foreign-key constraints:
"sensor_values_days_sensor_id_fkey" FOREIGN KEY (sensor_id)
REFERENCES sensors(id)

and I have a simple query that fails

Ie

SELECT sensor_id, MAX(ts), date_trunc('day', ts), COALESCE(MAX(value),
'NaN')::float FROM sensor_values_days WHERE ts > '2017-10-06
00:01:01+00' AND ts < '2017-10-06 23:59:59+00' GROUP BY 1, 3 ORDER BY
1, 2;
sensor_id | max | date_trunc | coalesce
-----------+-----+------------+----------
(0 rows)

If I remove the timezone part of the start date I get results.

Ie

SELECT sensor_id, MAX(ts), date_trunc('day', ts), COALESCE(MAX(value),
'NaN')::float FROM sensor_values_days WHERE ts > '2017-10-06 00:01:01'
AND ts < '2017-10-06 23:59:59+00' GROUP BY 1, 3 ORDER BY 1, 2;
sensor_id | max | date_trunc | coalesce
-----------+------------------------+------------------------+----------
597551 | 2017-10-06 01:00:00+01 | 2017-10-06 00:00:00+01 | 13763
597552 | 2017-10-06 01:00:00+01 | 2017-10-06 00:00:00+01 | 8168
597553 | 2017-10-06 01:00:00+01 | 2017-10-06 00:00:00+01 | 9441
....
...
..

I'm sure I am doing something silly but can't see what.
Does anyone know what is going on here ?

I am using Postgres 9.5

Thanks