Newbie could use some assistance

update and question

The contractor found the cause of the whine referred to in my earlier post. The first attempt was to install rubber dampers between the floor joists and the brackets supporting the circulating water pipes. This didn't correct the problem so today they cut out a small length (~18") of copper pipe running from the desuperheater to the water heater and another small length on the return pipe to the DSH and replaced the pieces removed with plastic pipe. Voila, problem solved! Apparently there was a resonance from the heat pump being transmitted throughout the house through the water pipes.

My utility provides me, via the web, a daily update on my KWH usage. I now know that when we're away my base electric usage is ~10 KWH/day. When we're home, we consume an additional ~10-13 KWH/day. The Geo system, with the thermostat set at 76 and outdoor temperature ranging from the high 80s to the mid sixties uses ~20 KWH daily. For clarity, my usage totals ~ 40 KWH when we're home and the geo unit is running. My intention is to correlate this information with degree days and come up with some more definitive numbers.

I now have a new question. I have a 12 KW generator to power my home when there is a power outage. The unit is connected to a transfer switch which automatically switches over to the generator when there is a power failure and feeds selected circuits in the house. The geo unit, of course, is one of the selected circuits. The auxiliary electric heat function of the WF unit is not a selected circuit since it requires more current than the generator can provide. Sounds simple, but it turns out that the geo unit will not run if the aux heat circuit is turned off. The contractor advises that a relay, energized when the generator powers up and runs, will need to be installed. The output from the relay (with the correct voltage) will then be connected directly to the thermostat, providing power to the thermostat without activating the aux heat. Sorry if I'm fuzzy here but that's how I understand the situation.

I'm wondering if anyone here has encountered a similar situation and, if so, how did you handle it? Are there other options besides the relay?

As always, all comments and suggestions are greatly appreciated.

 

"I'm wondering if anyone here has encountered a similar situation and, if so, how did you handle it? Are there other options besides the relay?"

Yes, Anyone with a new FHP or H2O Furnace has this trouble.
Theory with some manufacturers is that if a compressor were to fail or short out that this permits the AUX heat to operate without interuption. Downside is a situation like yours. Remedy is to wire system transformer to line side of compressor contactor instead of aux. line side.

As always check with installer or manufacturer before making wiring changes as some systems are shipped as an assembly with aux. coil and are UL listed as wired. We wouldn't want to interfere with a UL listing when a simple second transformer and reliable, never failing, made in Mexico, sometimes buzzing, occasionally heats up and sticks......electro-mechanical relay can accomplish the same feat (if you get my meaning ). Seriously, changing wiring without at least your installer's support could impact warranty. A third way (since your installer doesn't mind wiring in a second transformer on an independant circuit) is to wire the primary transformer on a tertiary circuit accomplishing all goals without a relay.

Those who wish to avoid this situation, can look at Climatemaster or Bard equipment (among others) as their system transformer is wired to compressor circuit.

Good Luck,
Joe

 

Popoff,

Your contractor is correct. There is a relay that can be installed to resolve this concern. We would suggest you contact your contractor to discuss other options, as they are most familiar with the design and application. If they need our assistance, please have them contact our technical support staff for further assistance.

 

WF, thanks for the prompt response. I do plan to discuss this with my contractor but the relay was the only option he presented and I wanted to see if I had other choices. It would be my preference to avoid adding a mechanical device to the system if at all possible.

Are you able to comment on the options presented by AMI Contracting? Specifically, I would like to know which of them, if any, would not void my warranty.

 

12 kw genny may be marginal for an 026

I'd expect your geo to put a pretty heavy surge load on that generator every time the compressor cycles. That will be hard on the geo, the genny, and anything else running on the genny at the same time.

You may be a good candidate for an Intellistart, a WF option that reduces starting current

 

How'd you know? Good call!

I was told by the contractor and electrician that 12Kw would be a gracious plenty but the compressor does strain when it starts on generator power.

I'll look into the Intellistart option tomorrow. I wish my contractor would have told me about it. )-:

 

Popoff,

We spoke with our technical support staff in regards to your inquiry and they informed us that they have some suggestions. Please have your contractor contact them to ensure that your unit is able to run safely and properly on the generator. We are more than happy to work with you and your contractor in finding a resolution.

As for the IntelliStart™, engineer is correct. WaterFurnace’s IntelliStart™ is a single phase soft starter which reduces the normal start current (LRA) by 70%. Using the IntelliStart™ will also provide a substantial reduction in light flicker. Please find more information by following the link below.

http://www.waterfurnace.ca/Engineer/IntelliStart/IntelliStart%20Sales%20Sheet.pdf

 

I would really appreciate input from the members of this forum regarding my quandry.

My contractor and his electrician both assured me the 12 KW (50 amp) generator would be a good choice for back-up power for my home. I observed the geo (WF 026 LRA 52 amps) would not start on generator power when I tested the system. A few days later, the contractor's technician was here and he observed the WF unit was straining to start when I switched over to the generator. He reported this to his boss, the contractor.

I learned about IntelliStart from Engineer (on this forum) and mentioned it to the contractor. He came back a few days later with a price quotation to install one.

I feel the contractor should bear the cost to furnish and install the IntelliStart since he told me the generator would be adequate for my need and even purchased it on my behalf. I don't want to be unreasonable and would therefore like to hear what the members of this forum would have to say about my plight before I proceed any further.

Thanks in advance for your valued opinions.

 

Well...how much more would a larger generator have cost you? As long as the current generator will be adequate after the IntelliStart, and the IntelliStart and installation cost doesn't cost more than the incremental cost of the larger generator, then you still make out ok. Did I fail to consider anything?

 

Interesting viewpoint, shared by a neighbor who is facilities manager at a large university in the area.. Thanks!

I think the contractor goofed big time and was fortunate that I caught the potential problem (with the help of this forum) before it turned into a big problem during a power failure in midwinter. While I don't believe there is a legal obligation on his part, I do think he should have stepped up and taken the responsibility for his mistake.

Again, thanks for your input.

 

If Popoff is paying for(and asked for) "a system that works" then the contractor should eat the cost of the Intellistart. It is a necessary component of "a system that works." (given that the contractor has already installed 95% of the system!)

If Popoff said "I want an 026 WF and a 12k Generator" then Popoff should bear the cost of the Intellistart... Contractor delivered what was ordered.

If the truth lies somewhere inbetween, then they should split the cost.

 

Does anyone else think it odd that a true 12K generator would struggle from the load of a 2 ton compressor?

 

If we're talking JUST the compressor, then yes I think that's odd. We don't know what else was running off the generator at the time. If his fridge and water heater were also running, then no.

 

duplicate entry

 

A 12 K should run a 2 ton fine. If it is not then the question should be "what are the other burdens on the generator?" What is the compressor amp draw (are we sure compressor is ok)?
One could argue if it is a load problem, that the water heater and the refrigerator are the problem (not the heat pump) so why should the heat pump installer be responsible for the cost of the fix.
I'm not jumping to the contractor's defense, in fact soft start kits are required by the utility companies in my area....but I think there should be a thoughtful discussion on the capacity and expectation for this generator vs "who should pay" finger pointing.
Joe

 

WF 026 LRA is 52 Amps. Generac 12 Kw generator puts out 50 amps. Also installed a steam humidifier that draws 10 amps on circuit. Looking at 62 amps draw on a 50 amp circuit which doesn't even consider bulbs, tvs, water heater etc that might be on at time of power failure.

 

Again, I don't know what the discussion was specifically, but based on the information provided this generator can run this heat pump.
Might want to put humi on a circut that is not on the generator.
Might want to test start up amps of compressor.
Or not....
j

 

No offense, but your post is not very helpful.

 

Popoff,
i base my statement on waterfurnace's generator sizing chart. chart suggests a 10K can run a 2 ton (52 required starting amps, 10 k with allowed 30% dip on start-up provides 63 starting amps). you have a 12K. something may not be right.

will a soft start kit cure the symptom? maybe. i'd rather rule out other problems first.....and if there turns out to be another problem of some sort then, no, i don't think your installer should pay for "intellistart" for you.

actually i'm disinterested in who pays for the kit or how your humidifier is wired. i was more concerned that you not end up cold 3 months from now due to a bad compressor or generator.

nor was i suggesting a battery of tests for you to perform i.e. amp draw, i was suggesting questions you might ask the electrician and heat pump installer.

i'm "helpfully" asking questions that are intended to inspire a "bigger picture" consideration of the information before us.................no offense taken
Joe

 

Would you please direct me to WF's generator sizing chart? I've never seen it on their site.

I have tried to run the system on the generator on two separate occasions. The first time, I heard a "thunk" under the house and the thermostat, Honeywell Vision PRO, said "wait." I switched back to regular power and the system started normally after a few minutes delay. The second time, the installer's technician was at the heat pump while I switched over to the generator. He stated the compressor sounded like it was straining to start before it finally did. He reported this back to his boss but I never heard anymore about it.

I'm now looking at the possibility of an even larger potential problem. I was reminded the other day that the balance point of the system is 27 degrees F. The supplemental electric heat is wired in such a way as to be inoperative when the system is on generator power. I'm wondering now if I'll have any heat when I'm on generator power and the temperature falls into the teens or even lower?

My relationship with the contractor has deteriorated to where it's unpleasant to speak with him. He's told me I'm a "difficult" customer.

Sorry for the length of this post but this forum is becoming my main source of information. I'm more and more getting the distinct feeling that my contractor is not as knowledgeable about these systems as I had been led to believe.