Help, my heatpump is a snowball!

[hostage]

My fiance reported a loud noise coming from our outside unit. I came home and removed the shroud and saw there was snow built up inside the unit that the fans were hitting against. Reading a few articles people mentioned there was a defrost cycle. We turned off the thermostat, though on this programmable one I don't see a setting for emergency heat (heat coils). I am hoping the defrost cycle will work, I have a space heater sitting on the top of the unit to help melt it.

We did get a bit of snow this past week and even more tonight. The odd thing on is that on three sides of the side vents there is snow caked on it, but on the the wind blows from there was none. I am wondering if this is a freak thing or if I should get someone to take a look at it. It costs $90 for someone to take a look at something, though I normally tend to fix things myself (with the exception of surgery).

-Doron

 

[Boomyal]

Re: Help, my heatpump is a snowball!

Get someone to check it out. I really doubt what you see is snow. It is ice that forms on the evaporator. The defrost cycle is nothing but the system reversing itself to turn the evaporator into a condenser.i That is, heatpump actually goes into air conditioning mode which sends warm freon thru the outside unit, which defrosts it. Your reversing valve may not be working or, the frequency between defrost cycles may be too long. The heatstrips in your air handling unit has nothing to do with the defrost cycle.

In any case, do not run your heatpump until it is resolved. Iced up evaporators cause extreme head pressures in the compressor.

 

[Tim Frank]

Re: Help, my heatpump is a snowball!

Get someone to check it out. I really doubt what you see is snow. It is ice that forms on the evaporator. The defrost cycle is nothing but the system reversing itself to turn the evaporator into a condenser.i That is, heatpump actually goes into air conditioning mode which sends warm freon thru the outside unit, which defrosts it. Your reversing valve may not be working or, the frequency between defrost cycles may be too long. The heatstrips in your air handling unit has nothing to do with the defrost cycle.

In any case, do not run your heatpump until it is resolved. Iced up evaporators cause extreme head pressures in the compressor.

He's in Rochester. NY.....it's snow!!
The "drift" pattern (on the leeward side of the obstruction) is absolutely normal, though unwanted.

The defrost cycle can be lengthened to try and compensate for what hopefully was just a blip in climactic conditions, but the OP did not give any history to help us out....has this happened before? ....has he just moved in and doesn't know the history?....etc.

It is not unusual for a HP to be installed in a problematic location, and it may be that a move is required....the HP, not the OP....

 

[Boomyal]

Re: Help, my heatpump is a snowball!

He's in Rochester. NY.....it's snow!! .....

Duh!

 

[rivermouse]

Re: Help, my heatpump is a snowball!

I had the same problem. I replaced the defrost timer and it solved the problem. I would carefully pour warm water over the frozen ice to melt it . Hope its not the reverse valve because that's something that requires the freon to be drained before the part can be put into the system. The best way to check it for being just the defrost timer is to turn the heat off and the ac on. If the ice starts to melt it most likely is the timer. Of course you cant run the ac long or your house will get cold quick. The ice forms quickly when the humidity is high. You shouldnt let it run with the ice build up because it puts strain on the compressor.The defrost timer isnt real expensive compared to other repairs( aprox 125 bucks on my trane) and you should be able to replace it yourself if you are careful and turn all power to the unit off first.

 

[bigdee]

Re: Help, my heatpump is a snowball!

What brand? Some heatpumps ( the higher end ones) have sensors to detect the optimal time to initiate the defrost cycle. This type is more complex than the lower end heatpumps that use a time based defrost that cycles at the end of a time delay whether it is needed or not. The lower end is more reliable and if it fails it is usually just the defrost board. The delay times can be set with a jumper that is mounted on the board. The 3 most common options are 30,60 & 90 minutes...if yours is set to 90 and if the climatic dewpoint in your area is high it may require a shorter defrost interval.

 

[Tim Frank]

Re: Help, my heatpump is a snowball!

Duh!

Yup, obvious.
But based on your post I figured you must have missed it to have erroneously dismissed it so quickly. Did you actually read the whole post?
You clearly missed this from OP :

The odd thing on is that on three sides of the side vents there is snow caked on it, but on the the wind blows from there was none

He is describing a drifting snow issue (the classic pattern!), NOT a frozen coil problem....even if

I really doubt what you see is snow

Guess what? it's snow! ....and they are getting another 10"-16" of snow and 20-30 MPH winds.
There's probably NOTHING wrong with the equipment!

 

[bassman284]

Re: Help, my heatpump is a snowball!

Yup, obvious.
But based on your post I figured you must have missed it to have erroneously dismissed it so quickly. Did you actually read the whole post?
You clearly missed this from OP :

He is describing a drifting snow issue (the classic pattern!), NOT a frozen coil problem....even if

Guess what? it's snow! ....and they are getting another 10"-16" of snow and 20-30 MPH winds.
There's probably NOTHING wrong with the equipment!

Ummm yeah, well OK sure. I'm just an Iowa boy and pretty country so bear with me here. What I'm trying to figure out is, why is he using a heat pump in Rochester New freakiing York? Heat pumps barely work in Tennessee!! Iowa is roughly the same climate as Roch. NY and the only person I know with a a heat pump has a boiler running in-floor radiant heating along with a couple of pellet burners and just uses the heat pump in fall and spring when it's too warm to fire up the boiler. Heat pumps are fine if your local temp never drops much below freezing, but otherwise....expect them to freeze up.

 

[Tim Frank]

Re: Help, my heatpump is a snowball!

Ummm yeah, well OK sure. I'm just an Iowa boy and pretty country so bear with me here. What I'm trying to figure out is, why is he using a heat pump in Rochester New freakiing York? Heat pumps barely work in Tennessee!! Iowa is roughly the same climate as Roch. NY and the only person I know with a a heat pump has a boiler running in-floor radiant heating along with a couple of pellet burners and just uses the heat pump in fall and spring when it's too warm to fire up the boiler. Heat pumps are fine if your local temp never drops much below freezing, but otherwise....expect them to freeze up.

Surprised me too, but that wasn't the topic of OP's post.
That lake is a big moderating factor on their temps, so maybe their H/P season is extended somewhat.

 

[hostage]

Re: Help, my heatpump is a snowball!

I have a heat pump + emergency heat (i think coils that heat up like a toaster). Anyway I am not a HVAC specialist, though it was running yesterday until I bypassed the heat pump and using only emergency heat. We have no gas lines that run here and are all electric. For the fireplace we have a 100 lbs propane tank. We use municipal power and it is so cheap there is no reason to use propane lowest utility was $19 for our cheapest month and it is normally less than $75/month.

This is a Trane heat pump made in my home town of Tyler, TX. I have lived in the house for over 4 years and this is the first time I have ever seen this happen. It is made in 99 and it is a TWE030C140B0 model.

 

[fen-isl]

Re: Help, my heatpump is a snowball!

I have a heat pump + emergency heat (i think coils that heat up like a toaster). Anyway I am not a HVAC specialist, though it was running yesterday until I bypassed the heat pump and using only emergency heat. We have no gas lines that run here and are all electric. For the fireplace we have a 100 lbs propane tank. We use municipal power and it is so cheap there is no reason to use propane lowest utility was $19 for our cheapest month and it is normally less than $75/month.

This is a Trane heat pump made in my home town of Tyler, TX. I have lived in the house for over 4 years and this is the first time I have ever seen this happen. It is made in 99 and it is a TWE030C140B0 model.

I do this for a living 20+ yrs I agree it sound like snow or freezing rain if the entire coil all 4 sides were froze I would think more of a defrost issue. Reversing valves rarely go bad and are easily check with a temperature probe, most defrost issues are low refrigerant charge (system has a leak) bad sensor/defrost thermostat or circuit board defrost timers are obsolete most modern equipment is now circuit boards. lastly if your out door fan is dropping out would also cause a frozen coil,(all 4 sides) the old york units were easy to see if this was happening they stored sensor history and you would usually see a -40 liquid line temp. .. Also the model number you gave is for the air handler, what is the model number for the outdoor unit that is froze up?

 

[fen-isl]

Re: Help, my heatpump is a snowball!

Heat pumps are used in Canada also, old wise tale, from 1970-80's when the heat output was not as good as modern units, Google Carriers VNA heat pumps can run down to -30 but start loosing output around 18 degrees, uses a variable speed compressor up to 7000 rpm, also slows the indoor fan down to keep air warm when down in the 18 degree range, pretty cool unit. most heat pumps start to fall off around 30-35 depending on how well the house was insulated, heat pumps are best in a tight house, as they can not recover quickly like oil and gas, that's why its recommend to set the temp and leave it or not drop it more than 2 degrees, once they get the house to temp they usually can maintain with little need for backup

 

[fen-isl]

Re: Help, my heatpump is a snowball!

I have a heat pump + emergency heat (i think coils that heat up like a toaster). Anyway I am not a HVAC specialist, though it was running yesterday until I bypassed the heat pump and using only emergency heat. We have no gas lines that run here and are all electric. For the fireplace we have a 100 lbs propane tank. We use municipal power and it is so cheap there is no reason to use propane lowest utility was $19 for our cheapest month and it is normally less than $75/month.

This is a Trane heat pump made in my home town of Tyler, TX. I have lived in the house for over 4 years and this is the first time I have ever seen this happen. It is made in 99 and it is a TWE030C140B0 model.

I do this for a living 20+ yrs I agree it sound like snow or freezing rain if the entire coil all 4 sides were froze I would think more of a defrost issue. Reversing valves rarely go bad and are easily check with a temperature probe, most defrost issues are low refrigerant charge (system has a leak) bad sensor/defrost thermostat or circuit board defrost timers are obsolete most modern equipment is now circuit boards. lastly if your out door fan is dropping out would also cause a frozen coil,(all 4 sides) the old york units were easy to see if this was happening they stored sensor history and you would usually see a -40 liquid line temp. .. Also the model number you gave is for the air handler, what is the model number for the outdoor unit that is froze up?

 

[hostage]

Re: Help, my heatpump is a snowball!

When I get suited up next I will check it out, we got what looks like 2 feet of snow 0_0. So is running the emergency heat going to cost a lot more than running the heat pump? Also our house is very well insulated. We even have insulation in basement ceiling (floor joists). The power company came in and did an audit the made our house more efficient for as odd as it sounds, for free.

Thanks for all the input.