Heat pump in winter, hunting for advice

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regency

Member
Nov 27, 2009
61
Mi
i know this isn’t the best spot but what the heck. I have a boiler which means no ducting for ac, the previous owners installed a multi split heat pump with two units. Question is, I only use it for ac and occasional shoulder season when too lazy to light a fire, the compressor can be heard outside if you listen closely constantly moving I assume refrigerant in case I was to tell it I need heat. Does anyone know if leaving it on is best since it keeps everything lubricated? I know I’m wasting some electricity but don’t mind if it’s better for the unit. I also understand everyone shuts off they’re central ac units simply starting them back up in the summer, thoughts?
 
It’s an electric heat pump, can provide 12,500 btu heat or ac, hoping someone may have insight if turning it off was a bad idea. I know if I needed it for heat and had it off, I would need to let it warm up before calling for heat, much like letting a fridge sit upright after laying it down. I don’t need it until it gets hot out as the heat it provides is minimal.
 
When you turn a ductless mini split on, the outside unit does its thing and gets itself up to temp before the inside one starts doing its thing. I dont think leaving it on will accomplish anything if not heating with it.

Make/model? Most good ones these days can give good heat at pretty cold temps. I've been using mine off and on down to -15c or so.
 
But if you had no intention on using yours for heat, you’d feel fine shutting it off? I dont think mine has ever been turned off as I don’t think the previous owners ever bothered
 
But if you had no intention on using yours for heat, you’d feel fine shutting it off? I dont think mine has ever been turned off as I don’t think the previous owners ever bothered

I have been doing it all winter. When it gets down below -10c, I usually turn them off. If it warms back up for a day or two, turn them back on. The remotes have an on/off button. Just like turning your TV on & off. If I wasn't turning them off & on, I would be setting them up & down. Do you do that?

Really see no point to running them on if they are not heating.

Again - what make & model do you have? We could be talking different types.
 
I’ll look tomorrow when I get back home fr the model, mine is off inside yet remains circulating outside at the condenser, only way to stop that is pulling the disconnect. Just curious if it is bad to let go dormant
 
Not really sure about all the details here, but it seems like if you arent using it, I would expect the best thing you can do is turn it off. Its a waste of power and putting runtime on the motor and all.... Most equipment can shut off fine.

Not sure if i understand the question, but the bigger problem is that if you are running the compressor (outside unit), but *not* running the inside blower at the evaporator, the refrigerant isnt properly heating back up and getting to the compressor. This would result in liquid getting to the compressor, its called "slugging" the compressor. It can damage the compressor...
 
Yup I think folks may be mixing up a conventional cooling only heat pump system with an integrated cold climate minisplit.

Some larger conventional heat pumps have sump heaters in the compressor sump to keep them warm year round. If the power is cut off to that type of unit it has to have the power turned on and left on for some predetermined period of time before the pump is started. I used to run into that on commercial roof top units frequently.
 
It’s a comfort aire Jackson heat controller Vmh 27tc. It has a crankcase heater and is functional to 5 degrees, it was powered on all last winter but thought of turning it off this year, don’t see the point in keeping it “ready” to power on if I don’t plan to. Unless it’s better for it’s overall health to stay warm to prevent oil from traveling where it shouldn’t
 
Yup its a conventional heat pump. It may run down to 5 degrees but my guess is its got a electric resistance heater for operation below 32 F. I have never heard of any issues turning off a crankcase heater for the winter as long as you give it 24 hours or so to run in the spring to drive the moisture out of the case.If its sealed compressor it definitely should not be an issue. If its a vented crankcase, there is some possible marginal improvement in longevity by leaving the heater on as it keeps moisture out of the crankcase.
 
Ok thanks, the other day it was 50 degrees out and the compressor was silent. Now at 20 degrees outside I hear what sounds like refrigerant flowing. I’m thinking it is slowly circulating refrigerant. It’s our second year in the house but I’d bet the previous owners left the power to it for years, maybe best to leave it be!
 
i know this isn’t the best spot but what the heck. I have a boiler which means no ducting for ac, the previous owners installed a multi split heat pump with two units. Question is, I only use it for ac and occasional shoulder season when too lazy to light a fire, the compressor can be heard outside if you listen closely constantly moving I assume refrigerant in case I was to tell it I need heat. Does anyone know if leaving it on is best since it keeps everything lubricated? I know I’m wasting some electricity but don’t mind if it’s better for the unit. I also understand everyone shuts off they’re central ac units simply starting them back up in the summer, thoughts?
I'm an HVAC technician but not familiar with that brand. Generally, as long as your are not shutting the 240v power off then you are ok. The units will have some form of protection against the cold. If you shut off the 240v then you must give 24 hours after power is reestablished before using the unit.

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