[baker_jeff]

Tonight I traded my Civic Si for a CRX Dx . The heater blows strong, but not hot air. Warm to sort of unfog the windows, but cold. When the car is sitting still, the temp gauge will go up to normal. Soon as you start driving, it will drop down to cold.

I'm guessing thermostat?

 

[downest]

Yeah sounds like it has no thermostat...

Although it's a DX for an Si, good trade, no need for those kiddy seats in the back!

 

[Savage]

valve behind the centre console check it.

 

[baker_jeff]

Where is the thermostat on a D15B2? Top or bottom rad hose? Please tell me it's easy to get to... its -20 celcius today and snowing like crazy.

 

[downest]

Bottom hose, pull it off and then unbolt the cover on the T-stat housing.

 

[baker_jeff]

Omg please help! I replaced the thermostat, poured Draino into the heater core and cleared it out, and bled the cooling system twice. It still does not blow warm air. It blows slightly lukewarm, and its -20 celcius this whole week. Google it.

The rad hoses are hot, the temp gauge is hot, I ran the car at 3000rpm for 10 minutes. It blows slightly luke-warmer at higher rpms.

The heater hose going IN to the core is hot, the one coming out is warm. Am I correct to assume that it could be plugged or not quite cleared out?

When I Draino'd it, I filled it with draino, let it sit for a few minutes, then put a long hose on to one end, sprayed it with a hose, then blew with my mouth until it was empty, it all came out no problem, with the occasional hiccup or air pocket it must have been.

Please help me I'm so COOOOOLD!

 

[bobski]

You've checked the coolant valve in the engine bay and the mix flap cable under the heater core?

 

[GSRCRXsi]

sounds like your heater valve is broken or the cable that pushes it is broken. have someone turn the knob on your heater controls while you look at the valve and see if it moves. you can probably manually adjust it for the mean time for winter but you might have to get it replaced eventually. not sure if its seperate from the heater core or not.

 

[88DXCRX]

For heat,the controller draws both cables in,So..
Push this valve toward the firewall:

Heater control valve:

Then position the air blend door as shown:


Located on the passenger side behind the console/radio..

 

[baker_jeff]

For heat,the controller draws both cables in,So..
Push this valve toward the firewall:

Heater control valve:

Then position the air blend door as shown:


Located on the passenger side behind the console/radio..

The hot/cold one was stuck, I've already made sure it's where it is supposed to be. The one in the engine bay is towards the firewall. What does that one do? What controls it?

Thanks for your help guys!

 

[88DXCRX]

It is just a valve..open or shut...

It controls hot water flow through the heater core
and it is actuated by the climate control temperature knob.

 

[baker_jeff]

I just double checked, both valves are where they are supposed to be. The heater hose coming OUT of the core is cold. I'm assuming that means its clogged?

 

[88DXCRX]

Just in case I confused you.. the valve shown in the picture above is closed..
It looks like this in the opened position:


You can remove the valve from the hose completely,
and then try to blow through the core itself by appling
air pressure to either on e of the two tubes..

 

[baker_jeff]

I FIXED IT!!!!

Filled the heater core with CLR, let it sit for 2 hours, came back out after watching a movie, read on the bottle that I shouldnt leave it anywhere for more than 10 minutes, drained it, filled it again and let sit for another hour, drained, put everything back together, filled with coolant, bled coolant.

I HAVE HEAAAAT