Heat Pump Report: First Season Finale

End of the 2008-2009 Heating Season --
Typically, Grumpy would turn on the heating system (formerly oil furnace) on 1 October and shut it off on 1 May -- if it hadn't already run out of fuel from the 500 gallon tank, that is. Some flexibility was permitted if an exceptionally cold spell occurred before the magical October date, or after the ultimate May date. In fact such was the case in Spring 2008, when the furnace remained on until the tank went dry on about the 15th of May. The Grand Mother wisely closed the kitchen door, when she got up at her usual early hour of 4:30 or 5 o'clock, and turned on the oven! She dared the Grumpy One to say a word about her method of achieving comfort.

Of course, Grumpy had long ago determined that his Bride's comfort was more important than an argument about the uneconomical method being used to provide that comfort. Besides, there was always that hope of another Lemon Meringue Pie!!

As an earlier post had complained, the cost of our regular July fuel tank fillup reinvigorated Grumpy's trade study for the most cost-efficient method of heating his Castle. As that earlier lament revealed, a Heat Pump was the way to go. The trade study predicted an annual cost savings (at July 2008 fuel oil price) such that the $8,000 initial cost of the Heat Pump would be paid off in about 4 years.

So now, on this the 12th day of May, the heating task has dwindled down to just a half-hour or so of operation to boost the "getting up" temperature to a "coziness"of 72 degrees. Then the system goes off for the next 23 1/2 hours. Thus Grumpy declares that the heating season is over for this year and proudly presents -- The results:

• $359.26 (greater amount of electrical energy consumed compared to previous year)
• $521.25 (fuel oil consumed @ July 2008 price per gallon)
• $2,119.55 (TOTAL savings using Heat Pump in lieu of oil furnace only)

Further to the benefit of the Heat Pump has been the fact that the Grump and Bride have had the thermostat set at 72 degrees this heating season instead of 69 or 70 like the previous year. One caveat: the Grand Mother insists that she doesn't feel as warm with the Heat Pump as she did when the oil furnace was running. Grumpy will not go so far as to say it is "all in her head" -- he senses the same thing! [It is a fact that the "hot air" coming out of the registers when the oil furnace is providing the heat is 20 to 30 degrees hotter than when the Heat Pump is providing the heat. The controlled room temperature, once it is warmed up, is exactly the same however.]

Heat Pump Operation Update

Thursday; South King County--
Since its operation began in early September, the Heat Pump has been performing properly and reliably. Most of this time the outside air temperature was well above 35 degr F, the temperature at which the installation technician had set the system to switch between the Heat Pump and the auxiliary heat (oil furnace). In December, when the outside temperature loomed into the 20's, and with high humidity, Grumpy reasoned that the switch-over temperature ought to be set higher to prevent frost build-up on the outside heat exchanger coils.

Sometime around the last part of December, Grumpy noticed that the Heat Pump was going into a cooling mode when the outside temperature was near freezing. Grumpy reasoned that this was a process to melt a frost build-up on the outside heat exchanger coils. Grumpy's professional (Mechanical Engineer) solution was to change the outside temperature at which the Heat Pump turns itself off and commands the "Auxiliary Heat" to take over.

But Grumpy became suspicious of the adequacy of his solution when, in early January the outside temperature got into the low- and mid-40's and the Heat Pump was still going into what Grumpy thought was the "defrost mode". So he changed the master control to use "Emergency Heat" only and called the people who had installed the Heat Pump.

Today (Thursday afternoon) the technician arrived, and after only a few moments, ascertained that the master controller had been programmed in reverse! Grumpy had obviously made a change that he hadn't intended to make! Now the heat pump is again working flawlessly.

Meanwhile, Grumpy gathered the data to show the progress of "saving money" with the Heat Pump as compared to depending on just the oil furnace. During the November-December period, we consumed 99 gallons of fuel oil and used 1375 kwh more electrical power than the previous year's period. Calculating that the Heat Pump provides the same heat as an equivalent quantity of fuel oil (211 gallons), Grumpy declares that we "saved" $449.10 this past two months! That's nearly $600 so far this heating season.

Note that the total "equivalent quantity of fuel oil" should approximate 500 gallons by sometime in April. That is the usual time when we have run out of fuel oil in past years.