why does my furnace whistle while running

Keyword Analysis

Keyword	CPC	PCC	Volume	Score	Length of keyword
why does my furnace whistle while running	0.38	0.8	1123	50	41
why	0.79	1	7220	63	3
does	0.78	0.5	9282	48	4
my	1.33	0.6	2211	89	2
furnace	1.51	0.9	1856	7	7
whistle	0.1	0.9	5136	11	7
while	0.43	0.9	212	70	5
running	1.47	1	6087	34	7

Keyword	CPC	PCC	Volume	Score
why does my furnace whistle while running	1.05	0.3	8663	60
why does a furnace whistle	1.48	0.8	9322	2
why is my furnace whistling	0.61	0.1	1201	95
furnace whistles when running	0.56	0.6	6159	60
why does my heater whistle	0.5	0.2	741	55
my furnace is making a whistling noise	0.54	0.7	7240	62
why is my heating system whistling	0.56	0.4	1763	15
furnace makes whistling noise	0.75	0.6	9145	12
why does my boiler whistle	1.25	0.9	5504	14
why does my gas boiler whistle	1.19	0.2	2307	21
why does air conditioner whistle	1.26	0.7	3744	86
why is my heater whistling	0.24	1	1362	100
furnace is making a whistling sound	1.05	0.3	4547	35
forced air furnace makes a whistling noise	1.5	1	8481	66
gas furnace makes whistling sound	0.31	0.5	2597	5
whistling sound from furnace	1.84	0.3	1187	31
furnace rattle while running	0.99	0.9	1541	97
whistling noise from gas furnace	1.87	0.7	8215	73
why is my air conditioning whistling	0.14	0.1	3547	65
why is my fan whistling	0.25	0.5	2753	83