Getting a price to replace my 21 year old WaterFurnace GeoHP

[Jerry_NJ]

I have been very happy with my Premiere Two speed 4 ton Geothermal (ground source) heat pump installed in 1993. It started needing rather expensive repairs to replace worn out rotating machinery: fan and loop pumps starting at about 15 years old. When it needed a compressor repair last December I was happy to find a new dealer (the dealer who installed my HP retired a few years back) and repair man serving my area for Water Furnace. He handled the repair in one visit.

I asked about replacing the then 20 year old compressor and he said Water Furnace no longer supplies a repair part for the compressor and no retrofit. So, when that fails one will be faced with perhaps a week or more without HP heat or cooling (the HP has 34 KBTU resistive emergency heat, but that would run about $1 an hour to run, possibly $700 or more for a month of heat in cold weather).

I took a peek at the current line of Water Furnace and asked him to give me a price for a replacement of my unit with a 5 Series (Two Speed, not Variable Speed) heat pump. I asked for a price with and without the ground loop pumping station being replaced. My current loop pump station will work with the new 5 Series and it had its two pumps replaced 3 years ago.. they should be good for another 10 years. I estimate. I also asked for a price to replace my existing 10 year old electric water heater and the cost of equipping the 5 Series with a DSH (think that's the abbreviation) tap to feed HP hot water into my (new or existing) hot water heater. My current system has the DSH but it never worked particularly well and that was in part to a poor design for the circulatory tap that was installed those 21 years back. The current way to connect the HP and Water Heater looks to be more effective. Water Furnace makes some rather high claims for savings on hot water using the HP... and of course with a COP of more than 4 and "Free" heat when cooling one could save significantly if the unit works as claimed.

Interested in any inputs on current GeoHPs and specific inputs on the Water Furnace current line, especially the 5 Series.

Interested on any neat "options" I should consider paying extra for.

I believe the replacement will qualify for the 30% federal tax credit, and I think there is a electric association rebate in the neighborhood of $500.

 

[sloeffle]

We have the Envision / 5 Series and have been very happy so far with it. It does supplement making hot water in the summer but you still need to run your hot water heater. I turn my the DSH ( de-super heater ) off when the temps are really cold to help keep my ground loops temps up.

Something that I was not aware of until this year is that you can order the furnace with a soft start option. I would highly recommend getting that if you plan on running the furnace with a generator. It drops the LRA from around 100AMPS to 35AMPS.

Have you looked at the 7 series ? It has a higher COP along with a variable speed pump, compressor and blower motor.

http://www.waterfurnace.com/literature/7series/BR2700AN.pdf

Scott

 

[Jerry_NJ]

Thanks, my power outage strategy, and I had 10 days off-line when "Sandy" hit the East Cost a couple of years back (still have down wood I haven't cleared yet) is a low power generator to run the refrig and a few CFL lights... and the blower on my airtight fireplace insert... and charge deep cycle batteries to use during the night and for periods of the gas gen being off. I had trouble getting gas the the small engine and 1 gallon would run me several hours.

Thanks for the great input on the 5 Series. I discussed the WF offering with the repair/installer/owner and asked about the life experience with the variable speed compressor - as noted my two speed is running 21 years now...with one repair to the starter circuitry last December. He said not enough data to know on the variable speed, but he thinks the two speed is as good (better Scroll now) life expectancy as my current. This is a bit at odds with my "notion" of what kills motors. start/stop but again, my two speed which was programed to go into Stage I at the first opportunity, is still running "like new".. but it isn't new (neither am I).

I believe the 5 Series, even my Premiere 45 (21 yo) had the program set such that "Stage III" was shutting down the DSH, "State IV" was the run up on resistive supplement, two stages approximately 5KW then 10 KW (really a bit less more like 17KBTU). My old system, a 4 ton, was strong enough that even in our coldest winters I think the resistive (almost) never cut in to supplement the HP.

I'm yet to learn what the DSH cost, some of this stuff is clearly the "High profit" stuff and we pay top dollar for it. The core has to be competitive the add-on like patents can draw big markups.

I'd like to have more manual control, for example, when I use firewood to supplement heat the existing 3 speed fan will run only in low for the circulatory function, I'd like to be able to request the middle speed or even all speeds for circulation when the wood "stove" is running.

 

[moey]

If you get a DSH you must have a second tank ( buffer ) to realize any usefull hot water production specially in the summer. Also you may want to calculate if a 3 ton system will meet your needs.

 

[Jerry_NJ]

I don't understand the water tank concern.. I understand the potential advantage when there are occasional large demands for hot water. My dealer suggested an 80 gallon single tank, and with only two old folks using the hot water that could act like a two tank system if we could turn off the bottom element. The we'd have (approximately) a 40 gallon resistive heated fed from a 40 gallon HP driven pump. The circulation I have in my current system is the DSH is feed from the bottom of the tank and returned to the bottom via the filler line. That's how I modified my current unit - it was not the way that was used 20 years ago when both in/out was at the common drain port via a single coupling with a narrow ring to feed water back in. My dealer asked if I put some kind of a valve in my return, via the cold feed, I said no. He said one is needed, don't recall what it is, perhaps a valve that shuts off the DSH pump flow when the tank is taking in additional cold water.

Why a 3 ton, is the target to get a small as possible to gain efficiency, yes I understand dehumidification can suffer from a too large cooling power. I really don't understand the Ton rating anyway as all unites are specified in BTH/H...and none have 36K or 48K (3 or 4 ton) in the listing and the cooling is always the higher of the ratings. I'm happy to have a slightly oversized unit that runs a lot in Stage I (talking two speed here) as the additional capacity makes the lower speed extra high efficiency. Have to go back to check, but I recall the 5 Series Water Furnace with a COP close to 5 in Stage I. Ther trick I'd like to have is some override of the control board via the thermostat. I'd like to be able to force the system to stay in Stage I as well as restrict/override the auxiliary resistive cut in ... say make the time delay for aux to be 1 hour, say. This would allow recovering from a few degree set-back at night resulting in a hit of resistive heat in the moring when I ask for a 5 degree raise in the room temperature. As for staying out of Stage II, I also use some "wood stove" wood heat and would like the HP to not go into Stage II when I am supplementing heat in one room.

 

[moey]

Efficiency in stage I and stage II are nearly identical. Most efficiency charts if you look closer at them have a higher incoming temp for stage I in the ratings then stage II. This does not happen when you run your system. You need to make comparisons at the same incoming temp. I don't know why they do that. I dont know why you would want to shut off stage 2.

If you shut off the bottom element on your tank off you'll have cold water when its 40F and sunny outside and the system is not running much. It just does not work well. The tank does not have a magical dividing line youll have cold water. Ive tried I have one tank it was a bad choice. In the summer you will not get free hot water with one tank. The summer DSH output is a much lower temp 100F or so having only one tank is useless because one element will keep that water on the bottom close to that temp. Also with a larger system it will not run long enough in the summer to make much hot water. It may even cost more as you lose heat checking the temp of your tank periodically.

The smaller systems have higher efficiency ratings as well as a smaller blower. Of course if your load is 60BTU at 5F and you put in a 2 ton system youll have problems. You can run a a properly sized system be it 3 or 4 tons at less of a yearly cost then a oversized system. There is no debate on that. A oversize system costs more to operate. I know climatemaster has a tool to compare load on their systems. You can compare different systems when oversized the yearly cost is more then a system that deploys some electric heat. You do not get the stated efficiencies except in longer runtimes.

I think most thermostats allow you to set temperature offsets Stage I is used until the temp falls X degrees from the setpoint then stage II then resistive heat. I do this in the spring and fall to get longer runtimes.

geoexchange.org is good they are very helpful. Do some research dont assume because you had a unit that put out X btu that is the size you need.

 

[moey]

This is a spec sheet if you take a look at output for Stage 1 and Stage 2. The COP are calculated with EWT temp of 41F for Stage 1 and 32F for Stage 2. That is the reason for the different COP's between stages. In reality youll see very close EWT for both stages so your COP is about the same for each stage. I think they use the 41F so the industry can say they have a COP of 5 you may see that in Sept but not in January.

http://www.waterfurnace.com/literature/5series/SC2500AN.pdf

 

[Jerry_NJ]

Moving forward on the Water Furnace 5 Series. The 049 and the 038, both are two stage with variable speed blower. My dealer's first proposal is for the 049.

I asked my dealer today to run both the 049 (4 ton cooling) and 038 (about 3.5 ton cooling) to see what the economics give. I'm sure the way I operate the 038 will work on heating too and will not call much auxiliary resistive heat even with a rated heating Stage II of only 26.7 KBTU. I like to run my wood stove fireplace insert on really cold periods. My house is a relatively small 2,000 sq ft two story built about 30 years ago for all electric heat. It has Anderson windows that could stand an update, but they are sound and double pane. My current unit has 40.5K Stage II heating capacity so the 038 could be working hard during a cold spell...running 24 hours a day.

I was concerned and discussed with him that the 049 may have too much cooling capacity to get the humidity out in the summer. Its Stage I cooling is 41K BTU and I fear it will produce a cool damp house on short hot humid periods. Besides, running more at a lower BTU will increase the amount of hot water I get from the throw-away heat at the HP when cooling.

I was quoted with the 049 with DSH that adds over $1,000, I am surprised it cost so much. He said the cost/benefit run show about a $300 a year saving on hot water, so the DSH will pay off in a little over 3 years. I'm also quoted with a A.O. Smith 80 gallon hot water heater that will interface with the DSH. I have a working 50 gallon electric water heater, but my plan is to junk that heater (over 10 years old) and not keep it in series with the new DSH feed tank. We will call the new Smith 80 gallon the "buffer" tank, as well as the hot water tank. Here I wonder about good operating strategies. Does the DSH put out real hot water? That is if I have the HW heater set at 120 degrees will the DSH be able to pump heat into that environment, i.e., is the DSH output higher than 120 degrees? One strategy I used on the existing unit was to turn the water heater off when the HP was running a lot. Then if someone was going to take a bath or we were going to run the dishwasher I would turn the HW heater back on for that period, and off again as soon as our high demand for hot water stopped. This gave the DSH many hours of the day and all night to store BTUs in the HW heater as if it were a "buffer" tank. Sounds like a lot of work, but I like to "mess around" with stuff : )_

He's quoted with the ECM variable speed blower, Intellistart, Performance and Refrigeration package, and 10 KW auxil heat package options. I understand the performance package will give a lot of trouble shooting information, stuff I like to read myself such as the run time on aux heat, temperature of the brine in my ground loop and other operational parameters. The quote is with the TPCM32U03 thermostat. He also said the control board can be set for longer delay in starting the aux heat. I like to do a few degrees set back at night - like a cool bedroom and would like to be able to ask for a 5 degree increase in heat without the aux heat jumping right in. This operating mode may make the larger 049 more satisfying as it puts out (have to look up again, think about 40 KBTU compared to 26.7 KBTU for the 038 and about the same as my existing Stage II heating).

I haven't gotten a second quote, must be a Climatemaster and others in this area, but I like the Water Furnace I have, and I like the dealer who has done one expert repair on my existing unit last December. Before Tax rebate I'll be out about $16K as we will continue to use my existing ground loop and pumps. These two pumps were both replaced about 3 years ago. So, my after rebate cost will run about $11K. The new system should save me only a few hundred a year over my current system, but spares me the grief of having the old HP fail (compressor can not be replace) on a cold winter spell and have to rush to get a new installation. I know my old unit with a COP (when new) of 3.4 in Stage II will be well out done with a COP of 4.0 or better with either the 049 or 038 on Stage II. Besides, 21 years is a good service life for the existing unit, and it has paid for itself about twice in fuel cost savings (I paid about $9K with $3K more paid by Jersey Central Power). And I'm still using the vertical dual ground loop for a number of more years. That will be recharged as part of the new installation.

My dealer says he can start work in about a week from the time I make a $5K deposit. It now looks like I'll go ahead for an early October installation.

See any serious faults in my thinking?

 

[DickRussell]

[quote=".........My current unit has 40.5K Stage II heating capacity so the 038 could be working hard during a cold spell...running 24 hours a day./quote]

If the 038 runs 24 hr/day with no auxiliary at design minimum outside temperature, then that's just the right size. I'm not familiar with the ATP32U03's options, but it would seem that if it supported two levels of auxiliary heat, then it might be prudent to split that 10KW aux between say 2 and 8 KW, with the 8 coming on only in the case of true "emergency" heat, to avoid that big hit at COP=1 when all you need is a little increment beyond what the HP delivers when you are below design minimum outside. In my case, for my 2-ton Climatemaster Tranquility 27, with ATP32U04 tstat, I have three zones operated by a zone board, and the board allows two stages of aux. I put in the minimum 5 KW aux coil in the unit and a 1 KW in the outlet duct. The zone board treats the 1 KW as first stage of aux, adding in the 5 KW only if it really needs to. I've got the zone board set up to run that way, but I've no idea if it works, as my HP hasn't had to go to second stage unless I've monkeyed with the tstat settings temporarily.

 

[Jerry_NJ]

Thanks, the "half pregnant" idea did come to me.. using something smaller than the 5KW steps to the aux heat. I know the proposed 10 KWATT aux/emergency heat isn't much heat. My existing unit lost the compressor last December and with just Emergency heat of about 34KBTU I didn't' get a lot of heat. Hum, wounder why that's up in the HP range.

My dealer called and said he ran the to sizes and put the results in the mail to me tonight. I'll study them over but it is looking more like I'll stay with the 4 ton unit. My only real concern is the cooling capacity may be too high, but then so is my current system in Stage II cooling, but it runs a lot in Stage I. Current Stage I cooling is currently 27 KBTU the 049 is 41 KBTU and the 038 is 20 KBTU. If my house was in the Washington DC area the 038 would be perfect as that's about the latitude were one needs as much or more cooling than heating capacity.

The other disadvantage of the 049 is less running time heating or cooling, thus less hot water at a COP of 4 or better and free when cooling.

I asked about the proposed system and he said the thermostat can set the Stage III delay to 30 minutes, which could allow me to run the 049 at a lower heating temperature at bed time, my preference and still have a hope of recovering the 5 degree set back from just Stage II (37KBTU). I also have a fireplace (wood stove) insert that I like to start on a cold morning to help bring the house temperature up.

I also discussed the proposed 80 gallon electric water heater for a combined "buffer" and Hot Water tank. He said that'll would we just set the lower thermostat as low as it will go, then the upper at 125 degrees if that's what we want. I'm considering disconnecting the lower heating element. We currently have a 50 gallon water heater and never run out of hot water. This idea assumes the temperature stratification in the water heater will feed the DSH with cooler water in the lower half, thus turning the lower half into a "buffer" holding area.

 

[moey]

I also discussed the proposed 80 gallon electric water heater for a combined "buffer" and Hot Water tank. He said that'll would we just set the lower thermostat as low as it will go, then the upper at 125 degrees if that's what we want. I'm considering disconnecting the lower heating element. We currently have a 50 gallon water heater and never run out of hot water. This idea assumes the temperature stratification in the water heater will feed the DSH with cooler water in the lower half, thus turning the lower half into a "buffer" holding area.

Setting the lower thermostat as low as it will go will not work. I can say that from first hand experience with a 80 gallon tank. I tried... You end up with luke warm water. You need two tanks to realize any gain with a DSH. The tank does not stratify like one would hope. If your not getting two tanks save yourself the money and dont get a DSH. Its unfortunate the geo companies and suppliers push the one tank setup presumably to sell more DSH.

 

[woodgeek]

Re the over-sized cooling....I am running a single speed 4 ton ASHP for heating and cooling not far from you. With 47kBTU/h cooling on a 2250 sqft house, it initially never ran more than 10 hours a day.

When I first got the system, I often had problems with excess humidity, mostly during the fall when the outdoor humidity was still high, but the outdoor temps had fallen. To deal with that I had the stat set to 'supercool'....if it detected humidity above some setpoint, like >60%RH, it would cool below setpoint as much as a few degrees. Not always super comfortable, but it worked.

Part of my problem is that my site is heavily shaded, no sun loads, and my finished basement is uninsulated....so lots of 'earth tempering'.

Since then I have (1) repaired bathfans for shower humidity and (2) airsealed the house, getting it to ACH50=5, and now excess humidity is not such a problem. I cruise around 50%RH all summer. With the airsealing and insulation work, my AC now never runs more than 7 hours a day (when its 100°F all day).

I would still like to get to lower %RH, I am planning on setting the CFM of my variable speed blower a bit lower for AC mode than it is currently....that lower the coil temp, and improves dehumidification. I would ask your installer about this option now.

So, you have options if there is too much RH....stat settings for super-cooling, source humidity control (fans), getting your house airsealed, summer blower CFM, etc. You're not the first person to have this issue.

 

[sloeffle]

We have the 049 with the ECM variable speed blower, minus the Intellistart . It heats and cools our 2200 sq ft ranch without any issues. I never hooked my heat strips up to the electrical panel because I don't want to pay for them to run. I figured the cost out one time and I think it was around 3.40$ and hour. Not sure if that was a good decision or a bad one. It burned me one time last year when it was really ( -10 to -20 ) cold but I just told the wife and kid to tough it out until I get the wood furnace going.

We do not have the buffer tank and my HVAC installer told me to turn off my bottom element on my hot water heater also. We ended up with luke warm water also.

If you are looking for a new hot water heater, I would look at the ASHP hot water heaters. Lots of talk about them on this site. If you are do not like the idea of a ASHP hot water heater then I would look into getting a Marathon. They are made out of plastic and have a lifetime warranty on the tank.

 

[woodgeek]

agreed on the HPWH. Figure a seasonal-average COP close to 2 in our area, and price it accordingly, with available rebates. If the DSH adds to the system cost and requires a second tank, its seems a HPWH is a better buy.

 

[moey]

We have the 049 with the ECM variable speed blower, minus the Intellistart . It heats and cools our 2200 sq ft ranch without any issues. I never hooked my heat strips up to the electrical panel because I don't want to pay for them to run. I figured the cost out one time and I think it was around 3.40$ and hour. Not sure if that was a good decision or a bad one. It burned me one time last year when it was really ( -10 to -20 ) cold but I just told the wife and kid to tough it out until I get the wood furnace going.

Not a bad idea to hook up the electric coil. Most thermostats you can basically program them out so they will not come on. At least mine you can set a temp offset of 10 degrees or so and also set the number of hours it would take of not maintaining a temp before the electric heat comes on. All it takes is for you to be away on vacation and have the HP quit for you to have frozen pipes.

 

[woodgeek]

You could also wire the aux's into the breakers, and just switch the breakers to off. If you are going out of town, turn them on while you are gone.

 

[sloeffle]

agreed on the HPWH. Figure a seasonal-average COP close to 2 in our area, and price it accordingly, with available rebates. If the DSH adds to the system cost and requires a second tank, its seems a HPWH is a better buy.

Good point. Just use the 1000$ from the DSH and put it too a HPWH. WIth gov't rebates you will probably be further ahead since it makes hot water year around vs summertime with a DSH.

 

[woodgeek]

On further thought, the HPWH will deliver cheap DHW all year long, because even in the dead of winter, it will be stealing cheap BTUs from your geo. Your total COP, even including heat stealing, could be 1.5-2 even in the dead of winter. I am sure you can get a Geospring, after rebates (with an extended warranty) for little more than a second tank costs, and just keep the DSH $1000 and the annual energy savings going forward.

 

[sloeffle]

Not a bad idea to hook up the electric coil. Most thermostats you can basically program them out so they will not come on. At least mine you can set a temp offset of 10 degrees or so and also set the number of hours it would take of not maintaining a temp before the electric heat comes on. All it takes is for you to be away on vacation and have the HP quit for you to have frozen pipes.

I could not agree more. I believe the HVAC guy set mine for 10 degrees also.

It has been on my todo list for about 2 years. Wiring them up is a lot harder than just running some wire across my basement. We only put a 100 amp panel in my house addition and the heat strips require 120 amps / 20kW if I remember right. So the wiring would need to snaked through a crawl space in conduit, up a wall and into the 200 amp panel in my house.

Not a fun job.

 

[woodgeek]

In retrospect, I wish my 15 kW aux coils were a lot smaller to give better comfort control when they are cycled on. They were sized for EM heat, now 10 kW would do the job 99% of the time. I could even go 8 kW and stash a couple cheap space heaters in the garage in case of (really unexpected) need.

 

[moey]

Good point. Just use the 1000$ for the DSH and put it too a HPWH. WIth gov't rebates you will probably be further ahead since it makes hot water year around vs summertime with a DSH.

Ive thought about this. I have a DSH and one tank so Ive considered putting the HPWH as my buffer tank use the HPWH for 9 months of the year and the DSH for the other 3 months. In retrospect I wish I add not gotten a DSH and gotten a HPWH but I drank the koolade given to me by climatemaster and my installer.

 

[woodgeek]

I could not agree more. I believe the HVAC guy set mine for 10 degrees also.

It has been on my todo list for about 2 years. Wiring them up is a lot harder than just running some wire across my basement. We only put a 100 amp panel in my house addition and the heat strips require 120 amps / 20kW if I remember right. So the wiring would need to snaked through a crawl space in conduit, up a wall and into the 200 amp panel in my house.

Not a fun job.

Strips are pretty cheap.

You could swap out the 20 kW strips for something smaller, and make the wiring job easier. 20 kW is 'only' 80A, or 100A wiring and breaker. 10 kW would be plenty for aux heat and useful for emergency heat, and only need 40A, or 50A wiring and breaker.

 

[sloeffle]

Ive thought about this. I have a DSH and one tank so Ive considered putting the HPWH as my buffer tank use the HPWH for 9 months of the year and the DSH for the other 3 months. In retrospect I wish I add not gotten a DSH and gotten a HPWH but I drank the koolade given to me by climatemaster and my installer.

I drank the kool aid also, so don't feel bad.

 

[Jerry_NJ]

Very interesting, I too drank the Koolaid 21 years ago when they didn't have a workable tap for the water heater and just tapped into my existing, which was 80 gallon. I somehow can't shake the attractive image of getting "free" hot water at least when cooling.

I'll talk more, maybe read the instructions, but more manual control at the thermostat is better than smaller resistive elements in my "book" I like wood heat so having to assist the HP in an unusual lower temperature turn would fit me just fine. I had the back up strips disconnected, disconnected the relays that cut them in. I could reconnect time in a matter of minutes for an emergency... but I prefer a "soft" or "Program control" approach.

 

[moey]

Very interesting, I too drank the Koolaid 21 years ago when they didn't have a workable tap for the water heater and just tapped into my existing, which was 80 gallon. I somehow can't shake the attractive image of getting "free" hot water at least when cooling.

The problem with the free hot water analogy in the summer is you only get 100ish degree water the compressor pressures are not high enough to make hotter water. The system also has to be running no free lunch when its a high of 75 outside unless you want your house 55 F inside. I think I ran my A/C maybe 10-15 times this summer and that is with it set on 70F which most people would feel is pretty cold. Of course you live further south then me we only had a couple 90F days.