Got a question regarding the realistic heat output from heat pumps.
Friend of mine living in South Texas has a hydronic heat pump system. Essentially a radiator run off a water heater providing the air handler the source of heat.
Overnight temps typically in the 30's. Daytime temps from the mid 50's to low 70's. Indoors the house struggles to reach 69 degrees.
I understand that heat pump systems aren't as effective as gas fired furnaces in generating heat but does this sound a bit weak?
What does this have to do with heat pump? No heat pump in sight here; and there's nothing anyways close to enough information to judge where the problems are with the system. Could be simply not a large enough water heater, could be it's large enough but the heat exchanger isn't sized adequately or the water flow or simply the setpoint is too low. Or, perhaps the house isn't insulated and is as leaky as a sieve; no way to know.
But, whatever it is, comparing to a heat pump isn't the answer.
I assume what he means is that it's a hydronic system that uses an air source heat pump designed for that purpose. And if it's struggling at those temps, it's not good. But like you say, not much info to go on. Like how old? Heat pumps have gotten a lot more efficient and capable of delivering heat at lower outside temps in recent years. And are being used in more places in place of propane or oil systems. Certainly a heat pump system should work well in South TX climate.
From what I understnad about the hydronic system is there is a water radiator in the heat ducts. This only comes on if the air temperature comming out of the heat pump coils is not enough to heat the house. Just as the electric heat strips are for in the more normal heat pump.
If the outside air is only 30 deg, the heat pump should not have any trouble at all keeping the house at 70 deg provided the house has enough insulation , which it should if a heat pump is installed.
For many areas the temperature has to drop below 25 deg, maybe even lower before the cost of operating the heat pump becomes more than gas heat.
It was 18 deg here the last 2 nights and I have the thermostat set at 68 deg at night and 70 during the day and the heat pump has no problem keeping the heat at that temperature.
You are correct. I was mistaken when using the words heat pump. System is hydronic only.
Curious does the water systems on these require any direct maintenance? Such as in hot water baseboard systems some require bleeding of air. Anything like that needed for hydronic systems?
I think the OP is describing something like an Apollo system, where there isn't a separate boiler for heat, but a large domestic hot water heater that runs through the heating coils.
I was skeptical until I saw one installed but that worked fine, in the Virginia climate. If this one isn't keeping up with the Texas climate then something is malfunctioning.
Tim
I should have included that detail. Yes the hot water source is a single large water heater. Following instructions left by the previous owner I opened the valve to allow the water to flow.
Sounds weak, from here. I'm sure I would have said that if I were alive.
My general contractor-- a guy who's being doing excellent work for me for over 30 years-- says he's never met a homeowner who ended up happy with a heat pump. He quit installing them many years ago.
Chiefjim posted for all of us...
Doesn't sound good. Has he had it serviced lately? What is the age of the system and building? Leaky windows will cut performance. Did he have satisfaction operation last heating season?
Comfort and low cost to operate - what's not to like? I wouldn't want one in Wisconsin but about anywhere south of there they work fine.
Er, provided you size them correctly and install them correctly. I know you're happy with your contractor but perhaps this wasn't his skill set.
And, even in WI, a ground-source rather than air-source will be work well (albeit at some additional initial installation cost).
Guess that it depends on where one is at. I am happy with mine and so are lots of others in the area. Most days are above 30 deg F in the winter. It does get cold at night. Last two nights was about 15 deg and with the thermostat set at 68 during the night, it seemed to stay there during the night.
If one is where it is below 25 deg most of the winter, then it may pay to look into other sources of heat, or if the electricity is very expensive.
Managed to find the name of the installer and gave them a call. With hints from here and from them I did a little digging.
Checking all the circuit breakers was non-eventful as all seemed fine. Ret urn trip to the water heater closet again showed everything as it should be .
Following instructions from the installer I went to the attic to see if the house inspector had inadvertently closed a valve or opened a switch. Agai n nothing.
Returned to the thermostat to verify settings. Discovered through the proc ess of elimination that the fan control did not activate when set for AUTO. Instead selecting just the full ON position brought immediate heat. Quic kly brought the house to 74!
Leaving the fan selector in the on position I tried lowering the temperatur e settings. Worked fine.
For now I'm focusing my attention on that programmable thermostat. Figure if she treats it like an older manual variety by raising or lowering direct ly she'll at least have heat. Just the fan will be circulating air 24/7. I did not open the thermostat housing as I have not found a master shut off switch for the system. Having come this far I'd hate to fry something in the process. Gut feeling now is either the unit was incorrectly wired or p erhaps is simply failing.
What's the fuel source? Now that I'm dead, I can check and see if it will be available for a while longer.
Man, that blows!
This morning, I had the privilege of working on a miswired furnace. Lucky, I'd done some heat work while I was alive, and had some idea how a furnace is supposed to be wired. Beyond that much information, I'm wise not to comment.
I live in the upper Mid-South and in a 600 s.f. addition I had built onto the back of my house 8 years ago I had a heat pump installed. The heat pump does a great job on the addition and it's always toasty warm back there. I was a bit skeptical at first as the original portion of the house has a central gas unit installed but I've been very happy with the heat pump.
Hydronic and what fuel source? You said it was run off a water heater? Normally a hydronic system is run off a boiler. Sounds like this is some half-assed DIY system. If it's really a water heater, it likely doesn't have enough BTUs. Even worse if it's electric.
ts from here and from them I did a little digging.
eturn trip to the water heater closet again showed everything as it should be.
he house inspector had inadvertently closed a valve or opened a switch. Ag ain nothing.
ocess of elimination that the fan control did not activate when set for AUT O. Instead selecting just the full ON position brought immediate heat. Qu ickly brought the house to 74!
ure settings. Worked fine.
e if she treats it like an older manual variety by raising or lowering dire ctly she'll at least have heat. Just the fan will be circulating air 24/7. I did not open the thermostat housing as I have not found a master shut o ff switch for the system. Having come this far I'd hate to fry something i n the process. Gut feeling now is either the unit was incorrectly wired or perhaps is simply failing.
Every thermostat I've ever had, the thermostat did not activate the fan for heating or cooling. That was done by the furnace/AC, etc. The thermostat only activates the fan itself when you put on the fan switch to make the fan run regardless of the burner/AC.
These systems are common in the South. Gas fired water heater feeds the heat coil and seem to be good and reasonable systems.
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.