Heat pump frozeen over... grrrr....

RatLabGuy

RatLabGuy

You look like a monkey and smell like one too
Joined
May 18, 2005
Location
Churchville, MD
While we were away this weekend, our heat pump unit seems to have frozen over. Nice layer of ice/snow covering the whole outer casing, although the top (e.g. fan and grill) was clear. Looked inside, although the comrpessor itself was ok (it's inside abag/cover), all the lines have a nice thick layer around them.
It was kind of stuck in thermal shutdown... I turned the system off for a min, then back on, it cranked up.
I'm assuming that i twas a combo of the wather yesterday/last night, the cold-ass air, and ir bing pushed around it's limits. This has happened befopre, but only when we have snow/ice... e.g. no problems last week (or wheneveri t was) that it got so cold.
I tried defrosting at least the outside w/ lots of hot water, but it was clear there was no way I could get the inside. It's running ok now... after 3 hrs, we're up to a balmy 66.5 deg... but my expectations aren't real high given the cold weather out.
Any way I can get this thing defrosted?

FYI, my house is intended to use oil as the backup heat. However w/ teh price of oil what it is... I let it run out and disconnected it from the thermostat...and we just use the pump. It does a fine job, even when it's pretty cold... only have issues when it's REALLY cold...
 
It has a defrost circuit built in to it. If the defrost circuit is not working it will do what you say it is doing. The last time mine messed up, the circuit card was fine but the actual heater that heats the coil up was burnt out. There are different types of defrosters so you might need to call the HVAC guy and get him to look at it.
 
Turn it to AC function, it will deforst itself in a few minutes.

Mine did the same a few years ago when we had a lot of freezing rain. Turning to Ac thawed it out quickly and it hasn't had an issue since.

Think about it, your heat pump and AC are the same unit, in the summer, the heat is expelled through the outside exchanger, as you have felt EVERY AC unit you have ever walked by.

In the winter, you are taking that same heat, but using it INSIDE, and the cold is expelled outside.

The defrost mode Kevin Lawler is reffering to is a cycle where it will defrost the outter coils on a regular basis, but when it is too cold out or WET as it has been the last few days, it can't do it in the cycle time aloted due to the extra ice build up.

( this info is coming from the guy who freaked the fawk out when his heat pump performed this very function @6am one morning soon after he bought his house and it was his first experiance with a heat pump, it made a lot of noise, and then the fan finally came on and blew steam up and out, being inside the window, I thought it was smoke. I have since learned a little about how this all works)

Doing the AC trick will do this same function, only a little more thourgh
 
Yeah, a buddy suggested the same thing.
It's just hard to tell teh wife, "Hon, I'm gonna run the AC for a few minutes, okay?" when it's onlye 65 deg in teh house, lol.
But now that she's off to bed.... I'll give it a shot.
How long is a reasonable time to let it go? 10 minutes? I have set up a few space heaters, but don't really want to be blowing too much coo air in...
 
mine did it in about 15 min if I remember, but it was warmer outside at the time.

The down side of heat pumps is they are near useless in 20° weather. Mine has " heat strips" that come on to supplment the heating, and I hate it when they do ( I just imagine the cash drawer at the power company ringing open !)

Oh, and don't tell her, just do it. this is one of those times.
 
Yep. Heat strip weather. And I'd still rather be on a heat pump than oil or gas right now. That's friggin sad, too. Before the Big Storm, I was dying to get on propane over here. Now I'm in no hurry. My $220 power bills pale in comparisson to my friend's nat gas bill.
 
It depends on dew point and a lot of other factors, but heat pumps can be rendered ineffective by frost at as high as 50F. Once it gets to around 35F, it spends about half its time in defrost mode. Below that, it can't keep up anymore.

You need to order some oil. All heat pump systems in this part of the country have supplemental heaters for a reason.
 
Well, I ran it in AC for about 30 minutes... didn't change naything.. .except blowing col-ass air inside the house. Probably the coldest my AC has been i nawhile, LOL.
So, yeah, sounds like either it isn't heating up, or at least not enoug hto dent this cold-ass air.

The deal with the oil is... as said.. it's just pricy as hell... minimum fill is 100 gallons, that's $375 right there.
Since this is probably the last wwinter we'll be in this house, it's just really hard to swallow buying all that oil for the whole 3-5 nights we'll actually need it...
Anybody got about 10 gallons of fuel oil I could buy off em?

Actually, what's annoying is that in theory, thsi should be a very efficient system. Output BTUs per dollar, oil is still the best - for cold weather, right at the point where this pump falls off the curve. So *IF* the system would use oil ONLY at the right time, it would be very cost effective, b/c it would actually be pretty rare.

The problem comes in w/ the actual behavior, due to what is supposed to be an energy-saving super-smart digital t-stat... What happens is, if it is wired up the way it's supposed to be, it runs the heat pump normally, and runs oil only when the heat pump won't run. So what the stat will do is, when the pump goes into defrost/chillout mode (necessary every now and again), it will kick over to oil so you don't have a break in the incoming heat. Good, right? Well, no... b/c once it kicks to oil, it stays running it until it has tripped the target temp... whether this happens in 3 minutes, or 25. In the latter case, it has just burned oil when the pump would have doen the job fine after it was done with it's 90 second break... the result is, it ends up burning oil even when it's not very cold outside (e.g. october). The only way to defeat this behavior was by removing the backup oil system from the stat.

now, I THINK I can comprimise by installing a switch that will enable/disable the oil backup line on the stat...
 
Not to point out the obvious, but have you tried pushing the big red button? Mine acted up last year. Had me worried as hell. The fan would run and run, like it was trying to blow warm air, but the compressor and coil fan never kicked on. I thought it was a relay or something. 30 min of research later, I found the big red button. Works great now! I don't know what tripped it out the first time, but I'll do it again if I have to.
 
Well, I don't have a big red button on the pump... but I know what you mean...

It actually runs fine now, despite being so frozen over. It had tripped out, but I got it restarted by turning the system off, then on again.
 
RatLabGuy said:
I tried defrosting at least the outside w/ lots of hot water, but it was clear there was no way I could get the inside.
Click to expand...

try this, wait until the fan is blowing. take cold water and while leaing directly over the fan unit and looking inside ( I know it'll be cold, and hard to keep your eyes open, but hang in there) now, look at teh ice inside and dump the cold water in there on the ice.

This way, when you go back inside it'll feel about 50-60 degrees warmer than when you just soaked yourself.:flipoff2:

you may let the wife try it first though. :lol:
 
Yep, it was a fantabulous 62.5 this morning when we got up.
I ended up just turning off the heat pump when I went to bed 'cause the air it was blowing out the vens was clearly cooler than the ambient air temps. Thank God for space heaters.

Oh FWIW, for little heaters, my little ceramic heat kicks the ass of the slightly larger just-coil ones.
 
RatLabGuy said:
The deal with the oil is... as said.. it's just pricy as hell... minimum fill is 100 gallons, that's $375 right there.
Since this is probably the last wwinter we'll be in this house, it's just really hard to swallow buying all that oil for the whole 3-5 nights we'll actually need it...
Anybody got about 10 gallons of fuel oil I could buy off em?
Click to expand...

Are you fawking joking? If you're that poor and pitiful, go get two 5gal jugs and fill them up with #2 at the filling station. Shouldn't cost you but $34.

We need to nominate this thread for some kind of "best of" award for people going through an unnecessary amount of BS in order to save themselves a couple of dollars.
 
Have you had the refrigerant checked? The heat pump I had when we were in Wilmington froze up one night in the middle of winter and it was because I had a refrigerant leak.
 
VortecJeep said:
Have you had the refrigerant checked? The heat pump I had when we were in Wilmington froze up one night in the middle of winter and it was because I had a refrigerant leak.
Click to expand...
Same, mine froze up because it was low on Freon, call someone to look at it, or freeze, personally, I would call, I hate cold. I thought we had outlawed this kind of weather in NC.
 
You can do a lot to fix this problem. first, I'd check the refrigerant as that will cause this problem. You can also adjust the defrost time. The circuit board should have about 3 different settings for the defrost cycle.

do you have an auxiliary heater? Is it working? If you don't have one, go buy a 10kW aux heater, less than $70. Of course, you'll have to run a seperate 220V circuit to your heat pump for it, but its well worth it.
 
All the heat pumps systems I've seen have an "emergency heat" setting that kicks on yet another set of heat strips.. I was told to run them once a year to burn off any crap on them..

Don't yours have this setting on the t-stat?

High power bills < freezing in your own house
 
No auxillary heating source (AKA the resistant strips), b/c the oil IS the auxillary heat. Just a heat pump and an oil furnace.


saf-t scissors said:
Are you fawking joking? If you're that poor and pitiful, go get two 5gal jugs and fill them up with #2 at the filling station. Shouldn't cost you but $34.
We need to nominate this thread for some kind of "best of" award for people going through an unnecessary amount of BS in order to save themselves a couple of dollars.
Click to expand...

Oh crap, I am indeed an idiot. Should have looked into that. What's the diffeence between fuel oil and #2 deisel? I assume there's a viscosity and/or additive difference?
Well personally I don't consider $300 a couple of dollars, but that's just me. Not to mention the huge extra fees for a call on a holiday weekend.

I'm guessing it probably is a bit low on freon, that would explain it. When I had the summer service, it was a tad low and they topped it off, so I must have a real small leak somewhere. Oh joy. I'll get somebody out tomorrow (being a holiday and all).
 
RatLabGuy said:
Oh crap, I am indeed an idiot. Should have looked into that. What's the diffeence between fuel oil and #2 deisel? I assume there's a viscosity and/or additive difference?
Click to expand...

according to the oil guy that would fill my oil at a previous house... no enough to make a difference. I asked if in a pinch I could go get diesel and dump it in there. he concurred. Those more knowledgeable than I may correct me, but I'm thinking he said Kerosene could be dumped in there too.
 
Back when i was younger.. we lived in a house with a much older heatpump.. when it would freeze.. we would get the pasta pot out, and boil some water, take it outside and pour it over the heatpump and it would unfreeze everything :)
 
They're using plain 'ol red-dye diesel at my Dad's place these days.

There is a gas station or 2 that sells off-road diesel around here, might be worth a few calls to save the road use tax.
 
you can get that road use tax back if its used for something other than on-road vehicles. We use the same diesel for our cranes, trucks, AND forklifts and welders. We just buy all the same diesel and get a credit for the fuel put in the forklifts and welders...
 
fuel oil is indeed #2 offroad diesel, using regular diesel only costs more.

Using Kerosine requires slightly different jet in the mist nozzle, so I found out when I tried to run diesel in the furnace set up for Kerosine in an old trailer we rented years ago.

wouldn't stay lit, smoked like hell, the only way to get it right was to bleed it thru with fresh K1 kerosine.
 
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