HVAC help needed for Heat Pump

[BucksCounty]

I have an electric heat pump. Lennox H25. The condenser is from 1993. The unti in the house is 2003. I recently replaced (with help of buddy who replaces fans regularly for district where I work) the fan motor. But, the fan on the unit hasn't gone on the past day. But, the heat pump is still working and NOT on the back up electric. The fuse is not tripped either. The heat is still coming out of the vents, but not as warm as usual.

I tried looking at some HVAC sites and read some things about a starting capacitor? Also read about defrost cycle, but not for an extended period of time. I am really not sure of anything with this. Not familiar with any of it.

Any thoughts? Ideas? I will call a guy out tomorrow but I want to have somewhat of an idea of what to expect.

Any help is appreciated.

Just another reason to get the stove for the main house and replace the old insert.

 

[fbelec]

are you talking about the outside fan not coming on? if so, the motor may be good but the capacitor might be junk. or the switch contactor at the condenser. if it is a variable speed you might have a bad control board. when you are running the unit if the fan is not turning, but the motor is humming or getting warm it's either a bad starting capacitor, a bad running capacitor or a bad motor. follow the wires from the motor and make sure they are not pinched and broke. if you see any oil or oil film on the capacitor change it.
best i could do with out being there.

 

[begreen]

Yes more info needed. Could be a relay too. Depends whether this is the compressor motor or the air handler (blower) motor.

 

[BucksCounty]

Thanks guys. The fan or unit outside is not even humming. I am calling someone this morning. I am pretty sure it has something to do with the capacitor. I am not comfortable with messing with wires so I will have to eat it and call someone. When I find out, I will let you know. Thanks.

 

[semipro]

There are a lot of potential reasons for this:

- bad control board in outside unit
- compressor oil heater not working
- bad sensor in outside unit
- too cold (some units don't work below a set temp and rely upon resistance heating instead)
- bad contactor
- Bad control at main unit inside or bad thermostat
- etc.

 

[begreen]

Good tips sp, could be as simple as a bad thermostat wire. There are so many wires crammed into a thermostat on some of these units that I've seen them break at the terminal.

 

[basswidow]

Which fuse did you check? The outside unit will have a separate breaker or fuse box at the unti. Before spending a service call for a tripped breaker, I'd make sure it wasn't thrown on the outside or a bad fuse.

Good luck.

 

[semipro]

Which fuse did you check? The outside unit will have a separate breaker or fuse box at the unti. Before spending a service call for a tripped breaker, I'd make sure it wasn't thrown on the outside or a bad fuse.

Good luck.

In some cases there is not a breaker or fuse outside, its a "disconnect" instead which is basically a link you can pull to de-energized the wiring so you can work safely on the outside unit. Its required by code.

 

[basswidow]

Which fuse did you check? The outside unit will have a separate breaker or fuse box at the unti. Before spending a service call for a tripped breaker, I'd make sure it wasn't thrown on the outside or a bad fuse.

Good luck.

In some cases the there is not a breaker or fuse outside, its a "disconnect" instead which is basically a link you can pull to de-energized the wiring so you can work safely on the outside unit. Its required by code.

Yeah - it is a disconnect. Sometimes I've seen the box with the arm you throw to shut it off. In my last 2 houses, it's been a breaker/ or a fuse block. My wife was complaining the house was hot, yet the A/C was running. I told her to check the outside unit and see if it was running - (it was stopped). She opened the box and reset the breaker - problem solved.

I had a service call once and it turned out to be - just a thrown breaker. You really feel stupid when that happens.

You are correct - it's a disconnect.

 

[yooperdave]

i believe that some outside fans will not run after a certain temp. is this the case?

 

[BucksCounty]

Well I had the guys out today. There was a short on the connector outside. He said the shorts are common because of all the wires?? After he got the outside fan running, he said the outside wasn't getting 24 volts?? He said he could get the fan running outside, but the volts were not correct. He went to the unit in the basement to check the unit. He finally said there was a short, which then shorted the thermostat so the thermostat was not controlling the unit outside. He said the thermostat was only getting 13 volts. It is a Honeywell Vision Pro 8000 and I found in records from previous homeowners it was installed in 03. He said they need to come out tomorrow and install a new thermostat? Is this true or can the one I have be fixed? Is it a wire? The guy seemed honest to me? He said it will still be a honeywell push button but not a touch like the one I have.

Thanks for all the help. I wish I knew more about this stuff.

 

[fbelec]

what he said to you is possible. if the wires shorted it prob blew either the switching chip or micro relay in the thermostat. these electronic thermostats don't have any sense of humor. something not right and see ya later. that's why they are getting cheaper every year. i remember installing the top of the line honeywell t stat's years ago and they cost 200 dollars just for the unit.

 

[semipro]

Well I had the guys out today. There was a short on the connector outside. He said the shorts are common because of all the wires?? After he got the outside fan running, he said the outside wasn't getting 24 volts?? He said he could get the fan running outside, but the volts were not correct. He went to the unit in the basement to check the unit. He finally said there was a short, which then shorted the thermostat so the thermostat was not controlling the unit outside. He said the thermostat was only getting 13 volts. It is a Honeywell Vision Pro 8000 and I found in records from previous homeowners it was installed in 03. He said they need to come out tomorrow and install a new thermostat? Is this true or can the one I have be fixed? Is it a wire? The guy seemed honest to me? He said it will still be a honeywell push button but not a touch like the one I have.

Thanks for all the help. I wish I knew more about this stuff.

Sounds reasonable to me as long as you're getting 24 volts to the thermostat. Typically this is supplied by a small transformer mounted on the air handler.

I suggest you invest in a decent programmable thermostat.

 

[basswidow]

Dang -

I guess he'll get your for the second day call out too? Atleast it's getting fixed.

Turn that heat pump off and run that wood stove 24/7

 

[BucksCounty]

I spoke with him and he is only charging me for one service call.

I am already stressing thinking about when this damn thing is going to go. The outside unit is 1993. The inside unit is 2003. I asked him what it would cost, just so I would have an idea down the line, to replace the outside unit. He said I am a year too late as there would not be any R22 units to match up with the inside system. The inside unit seems perfectly fine and it seems like a waste that I just "need to replace everything."

He then brought up efficiency and a new unit would work better in the winter. Once I install the stove in the main house, the HP will primarily be used for AC in summer months though. He said PECO rates will soon be sky high (3 years). Is this true? I currently recieve a discount for being an all electric house. I have looked into switching, and private companies said the discount PECO offers for being all electric house is better than anything they could offer. The house is 3300 sq ft. and my electric bill last month was 275. I don't think that is too bad, especially considering I run an electric heater in 10 month son's room at night.

What do I do once this system craps out? I like to be prepared and have funds for when things do happen. Do I replace the entire system? Try to match the compressor to indoor unit somehow? Switch to oil(yikes)? The inside unit is only a 7 year old Lennox system. I would think Lennox would have anticipated this and have something to match, no?

 

[semipro]

You may want to wait and see what happens as far as tax incentives. You could have gotten a 30% tax credit on a high efficiency system last year. I've read that some of these tax credits may be extended but its undecided.

I think for now I'd just get what you have fixed if its less than $500 which it should be if its only a thermostat gone bad.

Good luck with it.

 

[basswidow]

Do you have natural gas available? Your electric bill seems reasonable to me.

I'd replace it with a split system once it goes. A high efficency gas heater with A coil a/c.

I had a heat pump 10 years down in VA and did not like it one bit. Now if I had a wood stove back then, I may have learned to deal with the heat pump better.

 

[BucksCounty]

No gas available.

 

[woodgeek]

I spoke with him and he is only charging me for one service call.

I am already stressing thinking about when this damn thing is going to go. The outside unit is 1993. The inside unit is 2003. I asked him what it would cost, just so I would have an idea down the line, to replace the outside unit. He said I am a year too late as there would not be any R22 units to match up with the inside system. The inside unit seems perfectly fine and it seems like a waste that I just "need to replace everything."

He then brought up efficiency and a new unit would work better in the winter. Once I install the stove in the main house, the HP will primarily be used for AC in summer months though. He said PECO rates will soon be sky high (3 years). Is this true? I currently recieve a discount for being an all electric house.

I'm using a HP as a primary heat source, buy from PECO, and also get the 50% discount as an electric heat customer (just 7.5 cents/kWh marginal above a base usage). The literature on PECO rates is sparse and hard to follow, but it is clear that the discount is being phased out over the next couple seasons, such that there will just be one rate, summer and winter (the summer rate is currently a flat 14.7 cents/kWh). IOW, your (and my) winter heating bill on a heat pump will at least double in good sized steps over the next couple years. The open question is whether the flat rate will also go up over the same period. I guess some central PA folks had the caps come off in 2005 just when NG was spiking, and they did see their rates triple. If PA stays well supplied in terms of coal, NG and neutrons, I personally would bet that the flat rate won't go up. Competition from other elec suppliers might also help.

I also have a working legacy oil hydronic system, so I have done the cost comparison. With my (2008) HP, at 14.7 cents/kWh, the HP is even (seasonally averaged) with $2.60 /gal oil. I don't think oil will be that cheap in the future (my current price here from the 'discount outfit' is $3.10/gal), so I'm still glad to have the HP. What to do about the rate increase? I'm aggressively airsealing and insulating my house--I'm down 25% from when I had the HP installed, and I think I can get another 25%.

Since I have two complete systems, I"m hoping that they will offer demand pricing discounts (they are rolling these out now for summer AC and DHW). I could let them shut down my HP for a half hour from time to time for a decent discount. If it was a problem, I could wire my oil system back in as a second stage on my tstat, and the tstat would automatically call it when it sensed that the HP was shut down. If I was evil, I could leave the resistive backup strip connected and my elec usage would actually spike (on a separate circuit) when they shut me down to conserve. I wonder how they will police that?? Smart grid here we come!

 

[fbelec]

i wouldn't worry to much about the system till something happens heat pumps from what i have seen get about 15 years give or take a few years. that gives you some time to put away a little something if you can for when it does break down. if you have to change the condenser they can always just change the coil inside on the air handler and that's that. go as long as you can with what you got. every year they have come out with better stuff and higher seer ratings. also when you do have to change, the new freon that is used now makes for a better heat side of the system at lower outside temps than the old stuff. last year i wired a ductless split heat pump in a above garage playroom. the outside and inside temps were in the teens when we fired it off and the warm air coming from that unit was comparable to a warm air furnace. they'll be a lot of change overs to the new unit quick if R22 freon goes the price route of R12. some places are selling R12 freon if you can find it for 300 dollars a pound. your typical house system might take somewhere around 3.5 pounds give or take for the size unit and length of piping.

 

[BucksCounty]

I am getting frustrated....quick. Guy came yesterday and replaced the thermostat. Said wasn't getting correct ampage on capacitor. Told him to show me what he meant. He said capacitor should be getting 5 amps, was only getting 1.5. He replaced that (another $95). $422 later for tow trips out, 2 hours, replacing capacitor, controller, and thermostat, everything is working fine. UNTIL I get up this morning, feeding the kid at 6:45, fan is running, I hear the thing sound different than usual, look outside and there is smoke coming from unit. I turn off heat, run outside and the thing is hot and there is a burning smell coming from it! Turned everything off. Nothing on fire (except stove in back room and now main house insert). What time is too early to call this guy back. I am not happy, something is obviously not right!

 

[woodgeek]

Sorry about the insulting question--but are you sure the unit wasn't in defrost? In current conditions (cold, high RH AND blowing snow) the defrost cycles are maxing out and my unit is making funky sounds and blowing impressive columns of steam every 60 minutes or so.....

Of course, we could both be right and you could have a malfunctioning defrost controller board--so it is stuck in defrost mode.

 

[BucksCounty]

Woodgeek, you were correct. Thank you. I called the guy and he called right back and explained what was happening. I guess I never saw it in defrost cycle this year and that was what the steam column was coming from the unit. I panicked and immediately thought the worst. Thank you to everyone on this post that helped with this problem. It is helps to know you can count on friends from hearth for advice, educating, and help.

Stay warm, I am going to chop some wood!

 

[warmhouse2]

I also have an all electric 1800 sf house with two heatpumps (approx age 10 years) our electic bill last month was $575.. So we installed pellet stove to heat the first floor. Hoping that makes next months bill a bit more reasonable as I dont want to spend $20K on new heaters.

 

[basswidow]

Woodgeek, you were correct. Thank you. I called the guy and he called right back and explained what was happening. I guess I never saw it in defrost cycle this year and that was what the steam column was coming from the unit. I panicked and immediately thought the worst. Thank you to everyone on this post that helped with this problem. It is helps to know you can count on friends from hearth for advice, educating, and help.

Stay warm, I am going to chop some wood!

I was thinking the same thing - defrost cycle.

I used to manage a large apartment property - and all the apt's had heat pumps. People just aren't used to them.

1st - they move alot of air to accomplish heating and that air is usually lower the 98 degrees so when you put your hand to the register - it feels cold compared to your body. Gas or oil heat comes out piping hot - heat pumps not usually unless the axuillary heat is on.

2nd - the defrost cycle does make the outside unit look like something is wrong. It hisses and whizzes and steam comes flying out ..... it's crazy.

When someone would complain that they're aux heat was stuck, we'd usually be able to identify which outside unit it was ... because it would be frozen (we called them snowmen). A clear indication that the defrost was messed up or it was low on freon. We'd manually thaw them by turning on the apartment's A/C as this would reverse the system.

yeah - I am not a fan of Heatpumps. I've seen too much negative with them.