Heater puts out warm air no hot air?

RREAPER

MEMBER
2003 CHEVROLET ASTRO
2.6L
V6
4WD
AUTOMATIC
87,000 MILES

Heater puts out warm air no hot air, with heater on warm air cold air 2 defroster vents do switch I I can switch climate control switch a little bit of change in warm air not very much. Heater hoses get hot in out heater core hoses get hot?

Saturday, August 24th, 2024 AT 7:42 AM

5 Replies

KEN L

MASTER CERTIFIED MECHANIC
48,380 POSTS

This can be one of two things either the heater core is partially clogged, which you can flush out using a garden hose, or the temperature blend door actuator is not closing all the way. Please go over this guide to help as well:

https://www.2carpros.com/articles/car-heater-not-working

Here is the location of the temperature blend door actuator so you can remove it and work the blend door pivot by hand to see if it makes a difference, (HVAC system on) van engine warm.

Images (Click to make bigger)

SPONSORED LINKS

Was this

answer

helpful?

Yes

No

+1

Saturday, August 24th, 2024 AT 11:59 AM

RREAPER

MEMBER
2 POSTS

Thank you, a place, to start. I will reply when I check things out.

Was this

answer

helpful?

Yes

No

Sunday, August 25th, 2024 AT 9:02 AM

KEN L

MASTER CERTIFIED MECHANIC
48,380 POSTS

Sounds good, let me know what happens please.

Was this

answer

helpful?

Yes

No

Sunday, August 25th, 2024 AT 9:37 AM

RREAPER

MEMBER
2 POSTS

Took motor cover off actuator works turns c-wise and cc-wise flushed heater core little debris came out flushed until clear water, refilled core with anti-freeze got a lot more heat? Can a little debris make that much difference?

Was this

answer

helpful?

Yes

No

Thursday, August 29th, 2024 AT 4:43 AM

KEN L

MASTER CERTIFIED MECHANIC
48,380 POSTS

Oh yes, you would not think it would, but a clogged heater core is a common problem. I would flush the core in both directions for optimal performance.