2008 Pilot Air Conditioning Problem

[QBS]

The air conditioning blows cool air not cold. When drained, on vacuum for about 10 min, then refilled it will work great for about 2 weeks then back to cool air again.fficeffice" />>>

We have now been playing this game of drain and refill for 3 years. There is no leak. Something in the act of draining or vacuum and re-filling fixes it for a few weeks. >>

Stumped and Hot in Texas.>>

[94eg!]

Just because there is pressure inside the system, doesn't mean there isn't a leak. So long as there is liquid refrigerant inside the system, the measured psi will be the same. There is no way to tell how much is inside the system.

[robs]

94eg is spot on. 1oz of coolant will show the same pressure as 1lb. You can't tell capacity by pressure only by weight

Have the system evacuated and the coolant weighed. If your putting more back in than what came out you have a leak, plain and simple. It's a closed system. Get yourself one of those dye additives (checking to make sure it's safe for the compressor seals and orings) and a black light. Look around at all the hose connections and at the compressor shaft behind the clutch assembly. Check the condenser for debris and puntures and evaporator behind the glove box. If the leak is there and I think it is, it sounds like it's a big one and you can't miss it.

feeling your pain in central TX good luck!

[hkellogg]

if you are gonna vacuum down you have to do it for at least 30mins min and till the gauge reads -30hg and holds that pressure for a minimum of 5 mins after vacuum

[REY9077]

Ok, this post interests me also. I have a 2008 Pilot that is doing the same thing. I started in November with it not working. I took it in, and the shop said that they had seen some Pilots come in with a bad relay on the fan. The fan was not cycling on and off at low speeds as it should, causing a heat build up, and the pressure icrease due to heat was causing the system to activate the pressure relief valve. They replaced the relay, drained the system completely by vaccume, and then charged it back by weight per system requirements, with dye being added. This lasted about two weeks. I did not take it back in through the Holidays, and took it in on Monday 1/9/12, and today, with the inside temp on LO, recirculate on, and the fan on high, it only blows cool air. Todays temps were in the 30's when this took place. I am only guessing that the system is low on coolant again.
When checked on Monday, the only place that showed any sign of the dye was around the service cores. They replaced both of the service core inserts and charged the system with dye again. Any ideas?

[rocky]

The shop should test with a dye that shows up in UV light. Commonest failure point is the condenser that fits in front of the radiator in direct line of attack for stones etc.


Sent from my Autoguide iPhone app

[REY9077]

When they charged the system in Nov. they did in fact use dye. The light only showed a leak near the service ports. It is my guess that the act of pulling the vacuume to evacuate the coolant, then charging the system, then forcing in the dye, upset the service port cores. This perhaps weakend them to have a failure point pressure less than what the relief valve is set at, thus leaking from the service ports as opposed to the relief valve. If dye shows up at the relief vavle on Tuesday when I take it back, what would be the issue then?

[94eg!]

When you un-snap the fitting from the port, the pressurized refrigerant (and dye) sprays out all over the valve core. Not a big deal, but it does spray UV dye all over the place. Usually you need to clean them off and see if dye continues to leak from that spot.