Cost and Heat Degree Days December 2014

This is so expensive I am considering changing to natural gas. Maybe will make it a project for the summer of 2015. I am glad I did electric to start though, will end up with an accurate baseline for comparison.

Cost and Heat Deg Days Nov 2014

System filled with Glycol

I pumped 30% glycol into each loop with the Axiom MF200 system feeder. It was simple to do. The volume of liquid in one loop in the system was at least twice what I expected so I ran out and had to buy extra.

 

Per day cost

Nov 1 - I have been turning the thermostat down bit by bit to find the lowest acceptable temperature because it has been warmer than needed. Today it is set down to 12 deg C (53.6 F) but it does not feel that cold. I can see this is going to get expensive because - winter is coming...

  

Heating system is operational on water

On Saturday Oct 18 2014 the system was turned on using water (no Glycol yet)
and it is heating the garage.
Boiler is set at 103 deg F.
Thermostat is set at 16 deg C (61 deg F) but it feels toasty warm in here.
 The Grundfoss pump is on low and putting about 2.3 gpm around the primary loop.
The Taco pump is on delta T of 10 deg C.
The pressure difference over the boiler is about 4 psi.
The pressure difference over the loops is also about 4 psi.
  Static pressure is set at 12 psi.

kWH meter showing the 1st 2 kWH consumed. 

Cost here is 11.931 cents per kWH.

System Assembly

Piping installed

  Changed out a couple of leaking copper unions for brass ones and took out some unistrut clamps  that interfered with aligning the unions.

Here are the electrical tools and materials to feed power to the two pumps 

and the Axiom system feeder.

 The square box feeds the two pumps and the system feeder plugs into the receptacle. 

The switch controls the Taco pump. The Grundfos is off of the thermostat.

 Here is the system completed with electrical, ready to be filled.

 The Taco sensors will go on later.

System Assembly, September, October 2014

Installing the system

  Here is the electric hydronic boiler being installed: 

10 kW HydroShark III from Menards in Minot North Dakota.

Stripped back the #8/3AWG Teck90 cable and entered it into the boiler using a 3/4" cable connector to a 3/4" coupling. The top end of the coupling has a "21" reducer bushing into which a 1/2" close nipple is screwed which fits the 1/2" hole on the boiler.

 See the 1/2" locknut that the conductors have to get through?

 

Wired

The power from the panel goes up through the kWH meter up top 

then swings around down to the boiler.

 

 Rotameter flow meter will monitor that the boiler is getting 

the right amount of flow and it will also be used to balance the loops.

 Dry fitting the pieces together

Soldering work table. The copper tube is in the mitre box 

where it gets cut with a hacksaw. 

 

Almost all up on the wall

Sketch, component list, proposed operation

electric hydronic system for 760 sq ft garage house addition

The above sketch (to scale, one square = 2") is a plan for installing a HydroShark3-10 electric boiler to heat a 769 sq ft attached garage.

Following are details about this plan:

Garage/House Addition - consists of a 21 x 21 garage, 14 x 6 entrance boot room, (2) 9 x 11 offices, and a 4 x 6 mechanical room. Built in 1999, 4" slab on grade beam, R20 walls, R40 ceilings, 2"  rigid SM styrofoam under and around slab, triple glaze vinyl windows, 2" insulated steel Wayne Dalton garage door and insulated steel ext doors. Northern Canadian climate, typically get 6 weeks of -30 to -40 C every winter. We get snow from Oct to April, sometimes from Sept to May.

Previous heating system - 33 gallon NG DWH connected to (4) x 100' long loops of 1/2" Kitec (it looks fine despite the class action lawsuit against it).  The old set up was a primitive open system which kept the building warm but the unit rusted out this spring. Now I have decided to switch to electric and upgrade to a proper pressurized clean closed system with 30% PG/water. I pressure tested the loops with air (via the previous piping system) last week at 40 PSI and it only dropped to 38.5 PSI over 12 hours so I know the loops are operable.

New component list:
Boiler: HydroShark3-10
Primary Pump - Grundfos UPS15-42
Secondary Pump - Taco HEC-2 Bumblebee
Flowmeter - Dwyer VFC141EC  0.5 to 5 GPM rotameter
Purge and Fill Valve - Webstone 58613
Air Separator - Taco 4900
Safety Relief Valve - Watts 30 PSI Series 335
 P/S Purge Tee - Webstone 58643
Y Strainers - 3/4" Asahi PVC
Expansion Tank - 2 GAL Amtrol or equiv
Temperature/Pressure Gauges - Watts LFDPTG-1-3 0-75 PSI 60-320 deg F
Isolation valves - Webstone 51703T
kWH meter - Itron Centron .5-200A 240V 1ph Type C1S  3 wire (Sangamo GCA0001)
P/S system piping - 3/4" L Cu soldered except the system feeder line which will be 1/2 L Cu.
System Feeder - Axiom MF200

Proposed operation:
Primary pump will be controlled by a dumb Honeywell 120V line voltage thermostat. When it calls for heat the primary will pump 2 GPM through the HydroShark which will be set at 120 deg F.
The secondary pump will be controlled by the delta T sensors, initially 20 deg F delta T.
System pressure = 15 PSI. The kWH meter will allow me to monitor the cost of heating the space at the current rate of $0.12 per kWH.

Future consideration - enough space was left on the wall so that a larger electric heater can fit if the HS3 is too small.

mechanical room stripped ready for install

Comments are welcome, thank you for any input.