charging r410a heat pump

[crabjoe]

I finally got my heat pump install finish ... Finally got the new thermostat (Prestige IAQ) installed ... and figured out by my vacuum wasn't holding...

Well the outside temp was 55F... I charged by weight.. added 1.2 lbs of r410a. Started the unit and the pressures were a tad bit low. 110/220 (vap/liq). The cover stated it should be 139/239... Being late and with young kids, I just don't have time for SH/SC right now, so I added till I got to 125/232 vapor/liquid. The new Prestige !AQ shows return and discharge temps and after 10 mins there was a 27F delta... I change the it to heat more and after 10 mins it there was a 29F delta...

So here are my questions... Do the delta T's look ok? Also, in heat mode, the manifold gauge was showing 350/350 L/H is this normal? I'm really confused about this because there's are the sticker on the condenser's cover says that in heat mode it should be 120/400 (vap/liq) I think the sticker for heat mode is just wrong.. How can the low side pressure be lower, when it's running in reverse?

Thanks all!

 

[zmaxmotorsports]

I don't have access to my charging scales/cheat sheets,dark outside.
I'd say let it run overnight then check pressure/ temp during the day when it warms up.

 

[brewchief]

The delta Ts look a little high to me, I would guess airflow is a little low.
You need to charge by sc/sh depending on metering device.

Look for a service port on the suction line inside the unit before the reversing valve, in heat mode the normal suction line service valve is on the hot gas line.
If the airflow is off the normal service pressure sticker won't be accurate, charge by subcooling or superheat and you'll be OK.

Sent from my XT1254 using Tapatalk

 

[crabjoe]

Thanks guys.. I'm planning on charging by SH/SC but working 60+ miles from home, I don't get much daylight, if any, when the outside temp is high enough... right now, my plan is to get back on it Wednesday since it's suppose to hit the low 60s. I hope the outside temp is above 55, when I get home...

Thanks again!