Heat pump hell

[wahoowad]

God I hate a heat pump. At least mine. I'm better off ignoring it, but sometimes I sneak a peak. Stupid me.

Mine enters aux heat a lot. I know as I can hear it click in. I've been ignoring it all winter because I know my unit is old and maybe weak, but lately it has warmed up and the damn thing is still kicking in. Today I hear it kick in (it had been running, not sure how long) so I go look. Oddly, the ambient temperature was showing as my programmed 'set' temperature on my Honeywell RTH7400D digital unit. Why would the aux heat kick on if I was at the set temperature? Silly me for asking, but I am.

While pondering this the heat pump finally shuts off. A few minutes later it kicks in again and I run over to see. Sure enough the indoor temp shows 70 and the unit is set to 70. This time no aux heat, but I again wonder what conspiracy is at play to eat my utility dollars? The damn thing has been running 30 minutes now and I've been measuring the temp of the vent output at 81 degrees. It is 54 degrees outside. My unit knows it is 70 because the display says so, and it knows it is supposed to keep the heat at 70. So if both are 70 why has it been running for 30 minutes?!?!?!

I had this same wacky bahavior with the old school mercury thermostat and had hoped this digital one would help. It hasn't. My 1987 'Energy Star' home (HAHAHAHAHAHAHAHA! Jokes on me!) is cold natured but isn't full of leaks, holes in the walls, etc. I do have lots of older inefficient windows, but at least they are double pane.

What the hell is going on? It is still running...this could be very normal, I usually ignore it and just let the damn thing run and try to shut it out.

 

[Sandor]

Have you had someone qualified to come check this unit out?

 

[wahoowad]

Yes. Every year or two I have a service technician come out because it always seems to run like crap. They add a little freon, but say it doesn't seem to have a big leak. Just needed a little. Last time we cleaned the coils, and compared the difference in how much the air was heated. Right now it is 49 outside and I'm getting 81 out the vent (without the aux). The technician said it is old (1986 model) but appears to be running good enough that he wouldn't recommend replacing it until something fails.

I have been at Lowes between my last post and this one. It was running when I left and is running now. I can't tell if it has been running the whole time, although has been running 8 minutes since I came home. I have checked twice and it is set to Heat and fanis set to auto, so it isn't set to run nonstop (not sure if I could even set it to that, just saying it looks like it should be cycling and not running continuosly). My frustration isn't that it seems to be running nonstop, but that it runs when it appears to be at the target temp. Even runs quite awhile when it is supposedly at the target temp.

 

[stoveguy2esw]

where is the t-stat located? if on an outside wall it could be reading a cooler temp through the wall, also i have heard of some typeds of "modular" homes which have interior walls that are "split" by the house "modules" leaving an air gap which gets cooler air inside of them from leakage upwards from under the home. the wall may be cooler than the ambient air in the room thus tricking the unit into running more than it seemingly should (justa "wag" but may be worth checking)

 

[begreen]

The first thing I would suspect is the Honeywell controller. We have a brand-new American Standard heatpump. The system works fine, but the super-duper AS thermostat is actually a Honeywell and I am not impressed with it.

My main complaint is that one can't control the temperature differential very easily and precisely as with other thermostats. I suspect that your thermostat is trying to maintain the temp within 1 degree. This means within a plus or minus half degree range which may sound great, but is silly. See if you can get a copy of the service manual for the thermostat so that you have the access codes to set this up. It is a PITA to adjust, even after you have the codes, but may be the answer to your dilemma. Given the ridiculous setup maze for my system it's easy to see why a tech would glaze over and walk away from or possibly mess up the settings.

FWIW, with the same outside temps, I am getting about 110-115 degrees out of the vents in a 1924, non-Energy Star, farmhouse. And I have to kick my system in the butt for aux heat to come one. Evidently, technology has improved.

 

[wahoowad]

I finally just turned it off, and will leave it off a bit. I don't think it usually runs all the time like this, but how odd would it be for me to check it out the day it chooses to get all wacky? It is like I am in some bizarro world. This, along with a bunch of other goddamn costly home projects/needs is dragging me down.

 

[begreen]

Sorry the home projects have you down. There are days when I think I'll never see the light too. Best to go for a walk and enjoy early spring then. Projects can wait a bit.

As to the HP, you should be able to program it to exclude aux heat. Barring that, you could switch off the aux heater breaker.

 

[DonCT]

How old is your heat pump? Mine is closing in on 18 years old and I have the same problems as you. The service company would do the same thing, recharge and tell me I may have a "minor" leak. It will work ok for a little while, but it soon resumes using AUX for alot more than I would have liked. My HP is just so inefficient anyways. I think it's a 4-6 SEER system. This is why I installed my stove. I couldn't afford the $400-500/month electric bills in the winter. The heat pump just couldn't keep up.

I looked into replacing it, but I was quoted anywhere between $4000 to $12,000 Needless to say, my stove was ALOT cheaper than that. I may end up upgrading it to a higher efficiency unit before I move, but that will only be because the old one is......well, OLD

 

[Sandor]

Wahoo,

Virginia is looking at deregulating the electricity market. Actually, the caps are expiring. Maybe extended for 2 more years,or not. If its dereged, look for a hefty increase in your electric bill. So, I would be working for improvements that reduce the use.

Coming into spring/summer, you may wish to join the BrotherBart/Sandor window shaker movement, and install of couple of Energy Star window a/c units. Great for dehumidification and cools for a lot less money.

Last summer, I paid $7500 for a new 3 Ton 13 seer Ruud heatpump, with ductwork, in a new home I built.

Or, you can heat with wood, use window shakers in the summer, and put off the heatpump install.

 

[mikeathens]

How old is your heat pump? Mine is closing in on 18 years old and I have the same problems as you. The service company would do the same thing, recharge and tell me I may have a "minor" leak. It will work ok for a little while, but it soon resumes using AUX for alot more than I would have liked. My HP is just so inefficient anyways. I think it's a 4-6 SEER system. This is why I installed my stove. I couldn't afford the $400-500/month electric bills in the winter. The heat pump just couldn't keep up.

I looked into replacing it, but I was quoted anywhere between $4000 to $12,000 Needless to say, my stove was ALOT cheaper than that. I may end up upgrading it to a higher efficiency unit before I move, but that will only be because the old one is......well, OLD

With an infant in the house, I decided to have a system retrofitted into my 1870 log cabin so that when we came home from work/daycare, it wouldn't be 45 F inside - vents, cold air return, 14 SEER unit - $6000 installed. Is your replacement system gold plated? Man, that seems steep for just replacement. They spent almost two weeks trying to fish ductwork under what used to be the back deck of the house (now an interior floor) with 6" between earth and joists.

 

[wahoowad]

I should bite the bullet and get a new heat pump. Mine is old and obviously unable to keep up. I also hate my inside air handler (noisy) but not sure anything can be done about that. I mean I can replace it, but location not easy to change.

Part of my problem is I hate to spend big bucks on "maintenance" like replacing/upgrading heat pump, appliances, carpet, water heater, etc. if they still actually work. But there is a difference between "work" and works well. That puts me where I am now - needing a bunch of stuff done and it always weighing on my mind. Maybe I'll get some stuff done now that college football and basketball seasons are about over. I better hurry though as August (college football starts again) is right around the corner!

 

[laynes69]

I was laid off from work for quite some time. Our fuel bills were 350 a month for a 1300 square foot home. The furnace worked fine, but was older than dirt and over twice the BTU's needed. I really didn't have the money, But I had it replaced. Our bills dropped down to no more than 135 a month and we were comfortable. Sometimes things work fine and get you by, but if you can spent some money it can save you in the end. Our furnace had paid for itself in that season. Our home is 150+ years old and we have gone through alot of renovations. Sometimes it can get a little overwhelming, but I look at it this way. A new home can have the same problems this old home has, but I don't have the stress of a new house payment. A little elbow grease goes a long way.

 

[titan]

Wahoowad, your "service techs" should know it's illegal to just top up the refrigerant level in your heat pump without first finding and repairing any existing leaks. :roll:

 

[wahoowad]

This thing is still driving me nuts. I think it has more to do with the thermostat than the heatpump. My target temp is 70 and the room temp is 70 (thermostat reads 70 and 70) - so why won't the damn thing shut off?!?!?! But it just keeps running. It won't kick in the aux heat right now as the temp differential isn't enough to trip it.

Seems like it can't get above 70 or it would since the unit just keeps running. But I don't want it above 70 - it is set to 70! Shut off you damn thing. Eventually it will, but sometimes it just seems to run and run endlessly even when it seems to have reached the target temp. The aux heat will come on if the inside temp is far enough below the desired temp, mine just runs and runs when aux heat doesn't come on.

Is this some kind of setting? I have the manual but see nothing in it that seems to apply.

 

[webbie]

I'm not familiar with heat pump controls, but does the thermostat require a differential (anticipator?) - without those, regular central heat systems would also run all the time....or cycle very quickly.

Heat pumps, especially older ones in more northern climes, can be a nightmare. Take the cost of electric heat and then add the ductwork loses, etc....and that's probably the most expensive heat available (when temp in low).

 

[DiscoInferno]

My thermostat (a relatively cheapo programmable) turns on at 2 degrees below and off at 1 degree above when in heating mode. (Reverse for cooling mode.) So it will never shut off if it doesn't get to 71 degrees in your scenario, but once it does it won't come back on until 68 degrees. This is to prevent rapid cycling I think, and I suspect all thermostats do something similar. I've never seen one where the hysteresis (fancy term for this) settings were changeable. If your heat pump can't get one more degree, then I would think something is wrong with it.