Heat Pump Problems
I have what is known as a ground sourced heat pump. What this means is that there are two wells. Water is pumped up to the heat pump from the first well. The heat pump extracts the heat from the water and returns the now colder water back into the ground via the second well. The heat is transfered to air and blown into the house to keep it nice and snug in the winter. The process can also be reversed to cool the house in the summer, like an air conditioner, but on steroids.
Waterfurnace Heat Pump, notice the spare parts, tools and commentary
This is all supposed to be super duper green technology. The heat pump is supposed to consume only 1/5 the electric power as a conventional furnace. Sounds good, don’t it. The basic mechanism of the heat pump is the same as a typical refrigerator and these things are very reliable. Sounds even better until you hear the real life practical matters.
When we bought the house it came with a heat pump which included an electric furnace backup. Well this original heat pump self destructed within two months of us taking up residence in the house during one of the coldest winters on record. While I dicked around getting a replacement we burned 14 cords of wood in the wood burning stove. That is a lot of wood (basically a truck load), and this with the electric furnace backup working full time.
It turned out that installing a conventional high efficiency furnace was going to be about the same price as replacing the heat pump including a ten year warrantee, that the conventional furnace did not have. So we went with the new heat pump approach. Now, the old heat pump had failed because the well water had corroded the heat exchanger in the heat pump (heat exchanger is a radiator). So I had the water tested to find out exactly how corrosive it was. Turns out the water wasn’t bad but it wasn’t good either. So as an option on the new heat pump we got the super Nickle Copper heat exchanger that would be immune to the effects of the water. And in due course the thing was installed and everything was great for two years. At the two year mark the first of many well pumps failed in the middle of winter of course. Replacing a well pump in the middle of winter is no fun, but being without water is even worse, read, the toilets don’t work.
We are now coming up on the fifteen year mark of the new heat pump. We are on our fourth well pump, and with installation, they are not cheap. Just before the ten year warantee expired the heat pump died and then it’s control circuit also went. But the warantee did pay up and we only had to endure two weeks of ineffectual heating while repairs were effected. Now we have a benchmark of how long the heat pump is going to last.
But that is not all… Copper pipe running to the heat pump has three times needed to be replaced along with the troubles of no heat and water leaking all over the place. The water pump control circuit has been replaced twice. But the biggest pain has been the water valve that regulates water flow to the heat pump. That sucker has died four times. This valve is electrically operated under the control of the heat pump and it’s not cheap. There have been lots of other problems, I don’t think we have ever gotten through a heating season without at least one visit from the service guys.
I put the blame squarely on the shoulders of my heat pump manufacturer Waterfurnace.Not only does the heat pump itself need to be more reliable but all the ancillary equipment also needs much better reliability.
These ground sourced heat pumps place huge demands on the water systems. Demands that typical water systems are not designed to deal with. Effectively, in winter time the furnace kicks in and it does not shutdown until spring. This means that the water is running full time.
On the positive side… when this thing is running it runs well. Low risk of fire. Efficient. Green, no smoke. Cooling is really powerful. Good quiet variable speed fan. Reasonable air filter.
Other beefs (may write about these later):
Thermostats
Water analysis
Well pumps
Support for heat pumps (Not too many organizations provide repair services)
Water systems
Electrical systems
Backup heat
