[skaterstan]

Hi all,

Wondering if anyone could help me with a heating problem in my 8th Generation Civic ES.

In the last couple of weeks the cabin heating system has become unreliable.

The problem is that it is intermittently blowing cold air, when hot air is requested.

This happens both when on manual temperature control and auto climate control.

As said, this is an intermittent problem, even on the same journey.

Any ideas?

Thanks

Martin

 

[lightningslow]

check the coolant

 

[veehexx]

checked your coolant level? sounds like it's low and water isn't circulating through the heater matrix.
edit: sniped

 

[Farqui]

Have you seen this? Climate Control - Civinfo Wiki

 

[skaterstan]

checked your coolant level? sounds like it's low and water isn't circulating through the heater matrix.
edit: sniped

check the coolant

Great, thanks. Will check tonight.

If it is low, would this indicate a potential leak?

 

[skaterstan]

Have you seen this?

Also great, will take a look at this also!

 

[veehexx]

Great, thanks. Will check tonight.

If it is low, would this indicate a potential leak?

quite possibly, yes. While i've not first hand experienced this on my own car, i'd expect a decent amount of water to be gone for it to cause heater issues. 20-40% low to cause heater issue. 50% or more missing, then i'd expect to see engine temp issues.

from my past Hondas, sometimes it's been as simple as a fault with the rad cap - bad seat or weak spring causing low coolant pressure (low coolant pressure = low boiling point, so it just boils off). There's also the possibility of a stone through the radiator, or non-working cooling fan. I'm sure plenty more, but lets keep things simple, quick and easy to being with

 

[skaterstan]

Thanks everyone. A top up of approx 0.5l of coolant seems to have sorted the issue.

It's going in for a service in a fortnight, so I'll ask them to have a look for leaks.

Sent from my Nexus 5 using Tapatalk

 

[Farqui]

Nice one. Keep an eye on the levels yourself mate.

 

[veehexx]

Glad to hear its not much and an easy fix.

 

[RA108]

I'm glad this thread popped up as I've been having the same issue. I looked last night and the expansion vessel seams empty and the pipe down into it dry.

I'm going to try and pop into a dealer this morning and get them to top it up whilst I wait and then take it from there.

I'd do it myself but the bonnet instructions tell you to fill the expansion vessel not the rad and the issue is, if the rad is pretty empty, I'll fill the expansion and a short drive later it will be gone (into the rad) which means lots of refills never really knowing if its being lost or filling the rad. Without express instructions on filling the rad and knowing when it's full, I'm thinking best to get a dealer to top it and then take it from there.

Will probably buy a large bottle of coolant just in case so I can keep it topped in any event.

 

[lightningslow]

You fill the radiator first from a cold engine, then the expansion tank. If you've got a leak the expansion tank will not fill th radiator sufficiently.

Just pop off the cap, stick in a funnel into the open hole, pour coolant into it until its full, turn the engine on, rev it till about 2K and the fans come on making sure the heating controls are set to the absolute highest they will go. Make sure theres no bubbles coming out of the radiator before you put the cap back on. Fill up the expansion tank and thats pretty much how you bleed your system.

 

[lightningslow]

If you need a new radiator Amazon have a sale on a new Denso Radiator for the 1.8 which is under £15 at the moment

https://www.amazon.co.uk/gp/product/B00DZM7828/ref=ox_sc_act_title_1?ie=UTF8&psc=1&smid=A3P5ROKL5A1OLE

Y

 

[RA108]

Juts thought I'd follow up. No sign of a leak. Dealer put approx 1/2 a bottle of coolant in the rad expansion bottle. Heater warmer and no issues since.

 

[Farqui]

Good, keep a regular check on your fluids levels and hopefully no further issues eh.

 

[drix69]

Hey guyes, my air conditioner stopped working, the fan also went at the same time.
Also my temperature control panel is not lighting up and not working could that be if fuse? and if it is which one is it?

PS : Any fuses for cruise control ? its not working.

It's a 2008 civic FN3

Thank you !!

 

[skaterstan]

Continuing issues

I thought this issue had been solved by topping up the coolant. However it seems to have returned.

I have diagnosed that the temperature of the air seems to be linked to acceleration. For example if travelling up a hill the air is nice and warm, when coasting down a hill or idling at lights the air becomes cold.

This suggests to me that it may be a water pump issue?

Any other suggestions?

Thanks

 

[Farqui]

Or the AC clutch, theres plenty of info in the How To's.

 

[skaterstan]

Long time since I originally posted, but thought I'd let you lll know the issue is sorted now, incase anyone has a similar problem.

The issue was low coolant due to a leak where one of the radiator hoses goes into the base of the radiator. The clip holding the hose had corroded so much it disintegrated in my hands! My guess is when it heated up and the pressure built up, then it would leak.

Garage sorted it for me as I was in a rush, but I think it would be an easy job to replace the hose clip.