1. TECHNICAL QUIETSIDE DPW Dual Purpose Water Heating Season 2008/2009
QS-DPW-CT-001

2. DPW Condensing DPWH Basic Model Features
2 models 99k & 120k Btu/h inputs
Tested AFUE of 90%
Provides both Heating and Domestic Hot Water from one unit
Modulating induction fan and gas valve for complete control
Wet recuperative heat exchanger to allow condensing to reduce
(<140 DegF) exhaust gas temperature allows venting in Schedule 40 PVC

3. What is a Dual Purpose Water Heater
A Dual Purpose Water Heater is a unit that will provide both heating water for space heating and also potable domestic hot water for washing from a single unit without any additional controls required
Domestic hot water is given priority over the space heating, and is activated by flow through the domestic hot water system
DHW is “on demand” and continuous, it will be provided as long as the faucet is open
Once DHW call is completed the unit will revert to heating the house as required

4. What is a Dual Purpose Water Heater
The Closed Loop Heating system and the Potable DHW system are
COMPLETELY SEPARATED FROM EACH OTHER
No Check Valves or other Hydronic components are required for this unit to provide both heating and DHW
This makes this system a true and better alternative to taking a tankless water heater and then adding the necessary components to enable it to provide space heating

5. What is a Dual Purpose Water Heater
It is not called a Boiler in North America unlike the rest of the world, this is because
It does not provide closed loop heating water at a temperature above 176 DegF
It does not have an ASME H stamp, therefore cannot be used in areas where this is a requirement
Internal Water Volume is less than 1 gallon
Therefore these units are certified by ANSI Z /CSA as a gas water heater

6. Applications – Hydronic Heating
1. Radiant Heating :
Almost the perfect application for this unit
Low water temperature adds efficiency to the system
Low water volume suits these ultra low mass type of units
However the only issue is not to slice the zones to thin as this can lead to short cycling of the unit when few zones are calling

7. Applications – Hydronic Heating
2. Fan Coils :
Good application
For maximum efficiency ensure that return temperature is low enough to allow high efficiency operation
Use an aqua stat on the air handler to allow indoor fan to cycle off when in DHW mode
May need 24VAC SPST relay to interface
For Air handlers (even one) with or without pumps we must use the Quietside Primary/Secondary piping arrangement

8. Applications Hydronic Heating
3. Baseboard :
Standard US Baseboard temperature is 180 plus DegF
IF baseboard is sized using these temperatures
Quietside DPWH can only make 176 DegF MAXIMUM inside the unit – Typically temperature delivered into the loop is approx 165 DegF
SO – We may need to add additional lengths of baseboard to the house

9. Applications Hydronic Heating
3. Baseboard (Cont):
∆T and Hi Flow rates can cause problems maintaining temperature in the system
We recommend designing system for a loop ∆T of 20 to 25 DegF to allow the system to inject enough 160/165 DegF water into the loop to maintain temperature and comfort
Return temps above 140 DegF back to the DPW significantly reduce efficiency and condensate production
Therefore care is required as may not be the best possible application, especially in a true retrofit scenario

10. Applications Hydronic Heating
4. Cast Iron Horizontal Radiator Panels
See baseboard issues regarding the water temperatures and ∆T delivered at maximum from the DPW
Very high water volume when compared to a radiant or AHU application
This can create flow issues and expansion tank sizing problems for the Quietside unit
Return temps above 140 DegF back to the DPW significantly reduce efficiency and condensate production
Therefore not a preferred application, without careful planning prior to installation

11. Which size of DPW? HOW TO SIZE THE UNIT
1. Size the unit to the heating load of the house
THEN
2. Size the unit to the domestic hot water usage of the household.
Use the total max DHW load possible,
i.e. count all of the faucets or appliances that can be used at a single time, that will be your max DHW load, e.g. Shower and faucet, Shower and Laundry etc etc etc

12. Which size of DPW?
IT IS NOT ACCEPTABLE TO JUST PICK THE LARGEST UNIT IN THE RANGE BECAUSE OF THE DHW REQUIREMENT
We must ensure that the unit will modulate down to meet the heating load of the house, providing that the load is above minimum modulation level
Short cycling will reduce efficiency and promote component wear

13. Sizing the DPW unit Q : What is the MINIMUM OUTPUT capacity of a DPW?
A : DPW 099 – 47,000 Btu/h
DPW 120 – 47,000 Btu/h
Values based on net IBR calculations

14. But I have small Zones?
Q : My smallest zone is 10,000 Btu/h what can I do to prevent short cycling of the unit?
A : Quietside recommends that the smallest zone on the system should be 25% of the rated unit input or 60% of the minimum output shown in the previous slide
In the above case we either need to increase the size of the zone in question or ………………..

15. Get a Buffer Quietside offers a 20 Gallon buffer tank
DPW maintains the tank temperature and then system pump (field installed) acts as a primary loop pump
Prevents the DPW from short cycling

16. Sizing the DPW unit, Part 2
DHW Production : DPW099

17. Sizing the DPW unit, Part 2

18. Sizing the DPW unit, Part 2
Q : Still not enough DHW Production??
A : The DPW can be used very easily in conjunction with a storage tank for an instant supply of DHW – An old electric or gas water heater works very well
Use a bronze re-circ pump for temperature control in the tank OR
Use the Quietside range of Storage tanks which include all of the parts required

19. Sizing the DPW unit, Part 2
Quietside Storage Tank
20 Gallon
Comes complete with
Bronze pump
Mixing Valve
Check Valves
Aquastat to control pump etc

20. But I want to use a Tankless
Homeowners want to a unit to provide between 6 and 8 GPM of DHW, without a tank
All of these units MUST have a Max Input of between 180,000 Btu/h and 240,000 Btu/h for this level of performance
DPW has a maximum Input of 120,000 Btu/h with a 90,000 Btu/h being sufficient to heat most houses

21. I want my 8 GPM Gas Pipe Sizing becomes an issue
Standard House Construction (approx)
Boiler/Furnace 135,000 Btu/h
Storage Water Heater 40,000 Btu/h
Range/Fireplace 30,000 Btu/h
Total ,000 Btu/h
This requires a maximum gas pipe size in the house of 1” giving full capacity at 80ft of gas piping in the house

22. I want my 8 GPM Gas Pipe Sizing using a DPW with a tank
DPW (Largest) 135,000 Btu/h
No storage Water Heater required
Range/Fireplace 30,000 Btu/h
Total ,000 Btu/h
This requires a maximum gas pipe size in the house of 1”, with ¾” through most of the house giving full capacity at 80ft of gas piping – no change needed for a retrofit

23. I want my 8 GPM Gas Pipe Sizing using a Tankless for DHW
Water Heater 230,000 Btu/h
Furnace or Heating unit 135,000 Btu/h
No storage Water Heater
Range/Fireplace 30,000 Btu/h
Total ,000 Btu/h
This requires a minimum gas pipe size in the house of 1 ½” to giving full capacity at 80ft of gas piping in the house

24. But I want to use a Tankless

25. But I want to use a Tankless
Added Cost
Pump Taco 007
Expansion Tank
Brazed Plate
Flow Switch
Check Valves
Plus the venting……………………….

26. DHW & Well Systems Pump is required in a Well application
Pressure changes during DHW use can cause flow/temperature changes of DHW from DPW
Reduce differential on well Pump to minimize OR
USE A QSDHS STORAGE TANK to prevent this

27. Installation and Start Up

28. Locating the DPW unit Must be in an indoor location
Ensure that the temperature in that location does not fall below 45 DegF
Ensure that the Indoor humidity levels do not exceed 80%
Stay within the venting limitations, total equivalent length of 45feet, less elbows etc
Requires a solidly grounded dedicated 115V power supply
Ensure that a correctly sized gas pipe is available

29. Installing the DPW Remove unit from Carton
Unit installs on a hanging bracket mounted to studs or wall brace
CANNOT be installed on a combustible wall. Use non combustible backing plate e.g. Durarock or 24g sheet metal
Pipe condensate directly to the building drain
Comply with stated clearances to other appliances

30. Installing the DPW – Water
Connections, Left to Right
Heating Water Return : ¾” Male Union
DHW Cold Inlet (or tank) ½” Male Union
DHW Supply to house : ½” Male Union
Heating Water Supply : ¾” Male Union
DO NOT OVER TORQUE!!

31. Installing the DPW – Gas/Vent
GAS LINE SIZE MINIMUM OF 3/4”, flexible pipe to connect is acceptable providing it has a minimum capacity of 250,000 Btu/h
Drip leg required to prevent dirt entering gas valve
Venting : 3” Diameter
Intake and Exhaust is standard – connections go directly to 3” PVC
PVC cement, then seal around vent connection with high temperature silicone to prevent leaks

32. Installing the DPW EXPANSION TANK AND PRIMARY LOOP PUMP INCLUDED
Expansion Tank is equivalent to a standard 20 Gallon
Check your requirement for expansion especially if you are doing an old gravity system
Primary Loop pump, maximum flow through the Primary Loop is approximately 3.5 GPM
If you are using a higher flow on the system side it will blend down the temperature delivered in the heat emitters

33. Installing the DPW
Manual feed valve included on the unit – no pressure setting however it does have a check valve
Always installed an approved Boiler Feed Valve on the closed loop system
Make sure that Backflow prevention is included
Taco 335 or 329 is ideal
Screw the Quietside feed valve closed and do not open it

34. Installing the DPW Automatic Air vent included inside unit
Air Elimination is very important with these types of units
ALSO INSTALL ADDITONAL VENT AT HIGHEST POINT – AIR REMOVAL IS SINGLE LARGEST CAUSE OF FAULT CODES

35. Installing the DPW Note : THE PLASTIC SIPHON AT THE FRONT OF THE UNIT
IT MUST BE FILLED PRIOR TO THE START UP OF THE UNIT
Fill To Here

36. Venting the DPW
When installing the venting ensure that the Exhaust Flue is sloped back to the DPW approx 1” per 2ft horizontal to allow condensate from exhaust gases to return to the unit for draining – this will also reduce the build up of ice on the termination during cold weather
Install termination snout to reduce ice build up, caulk around the snout
Install 90 Deg Elbow and birdscreen on the inlet air pipe

38. Vertical Venting the DPW
Respect the maximum vent lengths and elbows
Always use 2 x 45 Deg Elbows on flue pipe
Use the snout that is provided with the unit for the flue pipe
2 x Elbows are used on the Inlet pip providing they are in the same barometric plane, don’t forget the birdscreen
Vertical Venting addendum to IOM available on request

39. DPW Circulation Pump
The pump in the DPW has to overcome the head losses of the unit Heat Exchangers
Therefore the external head available to the system is much less than the gross pump curve printed, in addition the system is designed for higher ∆T’s than standard US Cast Iron boilers
Unit Flow 15Ft
External Head
DPW GPM
DPW GPM

40. DPW Water Piping THEREFORE WE MUST PIPE THE UNIT AS
FOLLOWS, NO IF’S, AND’S OR BUT’S
With a PRIMARY/SECONDARY LOOP with the unit injecting hot water into the secondary loop to be circulated by the loop pump(s)
We also have found that using additional pumps in series does not work well with the DPW
If retrofitting simply remove old unit – replace with pipe and Tees and then pipe up to DPW like this…..

41. DPW Water Piping

42. DPW Water Piping

43. DPW Water Piping

44. DPW Water Piping

45. Power Wiring the DPW Power Wiring
115V, 15 Amp dedicated circuit is required
Circuit and unit must be grounded
Unit has internal 3 Amp glass buss style fuses to protect the Microprocessor and other components
Seal around connection to prevent leakage

46. Zone Controlling the DPW
Several ways to for zone control of the units
Taco/Argo style zone controller
SR501 switching relay
SPST Relays allow interface with 24VAC Thermostats – e.g. Fan Coils

47. Zone Control Panel Wiring

48. Zone Switching Relay Wiring

49. Zone Switching Relay Wiring

50. SPST Relay Wiring

51. DSR-100F Unit Controller MUST BE USED
Will display Air Temp when first connected
Will display actual closed loop water temperature
DHW Water temperature is set from the controller
Fault Codes are displayed
DON’T ever put 24V AC to the DSR

52. Commissioning the DPW Once unit is piped, vented and wired it can be
Commissioned
Fill the closed loop system with water
Isolate DPW from the closed loop using the shut off valves
Attach hose from DHW water supply to boiler drain that is open to the closed loop system
Fill System – add glycol if required – Only use Fernox Alphii or No Burst glycol as they do not attack the seals – Maximum Glycol 30%
Once system is full, open shut off valves filling the DPW

53. Operation of the DPW DSR – Heating Water temp was set
Call for heat : Unit will pre purge
Pre Ignition
Open Gas valve (Solenoids)
Establish combustion at % capacity
Modulation to load using temp sensor in DPW
After Call Post Ignition
Post purge

54. More Domestic Hot Water
DHW Temperature is controlled but you MUST INSTALL A MIXING VALVE to prevent scalding
Minimum flow rate of 0.7 GPM is required to trigger operation in DHW mode
Flow switch is normally open – closed circuit = DHW mode
DHW production is always prioritized over heating function – also unit does not need to be in heating mode to provide DHW

55. LP Gas Conversion LP Conversion Kit Tools required Crescent wrench,
Philips/Flat screwdriver, Manometer
1. Change Gas Manifold
Then reassemble and follow set up instructions
Dip Switch #1 and 2 must be switched for LP
Gas Pressure set up is shown later

56. Inlet Gas Pressure
Natural Gas minimum pressure 5.8” WC, Maximum 9.7” WC
LP Gas minimum pressure 9” WC, Maximum 13” WC
If unit has been set up but still is noisy check Inlet gas pressure, especially under normal start up
There is not a tapping for Inlet pressure on the gas valve

57. Inlet Gas Pressure
ENSURE INLET GAS PRESSURE ON START UP DOES NOT CHANGE FROM THE INLET PRESSURE MEASURED WHEN UNIT IS NOT RUNNING
If this does occur a new regulator may be required

58. Annual Maintenance Routine Maintenance is recommended - Water
Check closed loop system pressure is still at 1 (15 psi)
Check for leaks at all unions and connections
Flush and clean Condensate siphon – carbon in the gas supply can give the siphon a dirty gray color, use a little washing up liquid to clean – refill with water
Check Auto Air bleed screw is loose

59. Annual Maintenance Routine Maintenance is recommended - Electric
Check all exposed electrical connections are secure Inspect for any signs of overheating
Check Dip Switch settings
Energize heating zones to check control circuitry, make sure DSR is set correctly to required water temps and mode

60. Annual Maintenance Routine Maintenance is recommended - Gas
Check Inlet gas piping, pressure for leaks and/or pressure deviations
Remove igniter check for carbon make sure connections to Ignition TX and flame sensor are tight
Start unit, check flame color
Switch into low fire mode check gas valve settings Re-check in High Fire mode

61. Annual Maintenance Routine Maintenance is recommended - Vent
Check termination for any blockage, make sure any debris is thoroughly removed
Check venting for any cracks or loose joints
Check Air Pressure switch operation
Check Exhaust Duct inside unit for leaks

62. Annual Maintenance Routine Maintenance is recommended - DHW
Isolate DHW system, then using hose bibs back flush DHW Heat Exchanger using lime away (pre mixed) or solution of ethanoic acid (Vinegar)
Repeat several times in areas of high mineral content to ensure removal of all debris

63. Checking Components Electrode and Flame Detector
Single Electrode so no gap, check the ceramic
The igniter has the pink marking
Electrode Voltage – 15-18kV DO NOT TOUCH!
Flame Detector – Faces away from electrodes
Flame Detector Voltage
200V to ground

64. Checking Components Strainer Closed system strainer on return side
Catches debris before passing through the pump
Held in place with a wire retainer, be careful when replacing it

65. Technical Support
Both East And West Coast Technical Support is available
East Coast : Hours 8AM to 5PM EST Tel : ( )
West Coast : Hours 8AM to 5:30PM PST Tel : x 3 ( )
Website –

66. DPW Warranty All models, FIVE YEAR PARTS – no labor allowance
Primary and Secondary Heat Exchangers carry a 12 Year warranty
Domestic Hot Water Heat Exchanger – 12 years

67. THANK YOU
FOR
ATTENDING
ANY QUESTIONS??