LAARS Mighty Therm HH-PH Installation Manual

Installation, Operation and Maintenance Instructions	Document 1064E

Installation,

Operation and

Maintenance

Instructions for

Mighty Therm

Hydronic Boilers

Model HH-PH

Sizes 175-400

FOR YOUR SAFETY: This product must be installed and serviced by a professional service technician, qualified in hot water boiler installation and maintenance. Improper installation and/or operation could create carbon monoxide gas in flue gases which could cause serious injury, property damage, or death. Improper installation and/or operation will void the warranty.

WARNING If the information in this manual is not followed exactly, a fire or explosion may result causing property damage, personal injury or loss of life.

Do not store or use gasoline or other flammable vapors and liquids in the vicinity of this or any other appliance. WHAT TO DO IF YOU SMELL GAS

•Do not try to light any appliance.

•Do not touch any electrical switch; do not use any phone in your building.

•Immediately call your gas supplier from a nearby phone. Follow the gas supplier's instructions.

•If you cannot reach your gas supplier, call the fire department.

Installation and service must be performed by a qualified installer, service agency, or gas supplier.

H0147400E

A subsidiary of BRADFORD WHITE Corporation

Page 2	LAARS HEATING SYSTEMS

TABLE OF CONTENTS

SECTION 1.
General Information
1A.	Introduction...................................................	3
1B.	Warranty .......................................................	3
1C.	Technical Assistance ....................................	3
SECTION 2.
Installation Instructions
2A.	General Information ......................................	4
2B.	Field Assembly .............................................	4
2C.	Site Location .................................................	5
2C-1.	Installation Information .................................	5
2C-2. Outdoor Installation (U.S. Only)....................		6
2C-3.	Flooring - Typical Installation ........................	6
2D.	Combustion and Ventilation
	Air Supply .....................................................	7
2D-1.	Outdoor Air Supply .......................................	7
2D-2.	Indoor Air Supply ..........................................	7
2D-3. Exhaust Fans or Vents .................................		7
2E.	Venting of Combustion Products ..................	7
2E-1.	General Information ......................................	7
2E-2. Replacement of Existing Boiler.....................		8
2F.	Water Flow System ......................................	8
2F-1.	Reversible Water Connections .....................	8
2F-2.	Freeze Protection .......................................	11
2F-3.	Pump Requirements ...................................	11
2F-4.	Variable Water Flow Systems ....................	13
2F-5.	System Pressure Requirements .................	13

2F-6.	Chilled Water Systems ...............................	15
2F-7.	System to Boiler Piping ..............................	15
2F-8.	Filling the System .......................................	15
SF-9.	Minimum Boiler Temperature .....................	15
2G.	Gas Supply and Piping ...............................	16
2G-1.	General Instructions ...................................	16
2G-2.	Special Precautions for Propane Gas ........	16
2H.	Electrical Wiring ..........................................	19
SECTION 3.
Operating Instructions
3A.	Setting the Temperature Controls ..............	19
3B.	Start-Up Procedure ....................................	20
3C.	Adjustment for Minimum Input Rate
	(Models with Modulating Gas Valve) ..........	20
3D.	Hi-Limit Switch Checkout ...........................	20
3E.	Shut-Down Procedure ................................	21
SECTION 4.
Service Instructions
4A.	Regular Inspection .....................................	21
4B.	Replacement of Gas Controls ....................	21
SECTION 5.
Parts List for HH and PH Boilers
5A.	General Information ....................................	22
5B.	Parts List ....................................................	22

Mighty Therm HH-PH Hydronic Boilers	Page 3

SECTION 1.

General Information

1A. Introduction

This manual provides installation and operation instructions for the Model HH and PH Hydronic Boilers, Sizes 175 through 400. Review all application and installation procedures completely before proceeding with the installation. Experience has shown that most operating problems are caused by improper installation.

The HH-PH boilers are offered in a basic configuration (see Figure 1). On PH boilers the pump is factory installed. On HH boilers the pump is field installed.

1B. Warranty

The HH-PH boilers are sold with a limited factory warranty.

Make all warranty claims to an authorized Laars representative or directly to the factory. Claims must

include the boiler serial number and model (this information can be found on the rating plate), installation date, and name of the installer. Shipping costs are not included in the warranty coverage.

Some accessory items are shipped in separate packages. Inspect everything for damage immediately upon delivery, and advise the transporter of any shortages or damage. Any such claims should be filed with the transporter. The transporter will not accept a claim from the shipper, Laars.

The warranty does not cover damage caused by improper installation, operation, or field modification.

1C. Technical Assistance

Consult Laars or your local company representative with any questions or problems involving the specification, installation and operation of Laars equipment. An experienced technical support staff is ready to assist in assuring the proper performance and application of Laars products.

OPTIONAL

V

DRAFTHOOD

VENT CAP FOR

OUTDOOR USE

DRAFTHOOD MUST

TOP VIEW

C

C

BE INSTALLED IN

THE FIELD

A

SIDE VIEW

HEADER

B

LOCATION

INLET

OUTLET

8-

1/2 in.

(216mm)

5-1/2 in.

40-9/16 in. (1030mm)

INLET OUTLET

30-3/16 in.

(767mm)

(140mm)

															26-1/2 in.
															(673mm)
	Gas Connection															C*				C
		Size			Water									C		(Indoor		(Indoor					V
					Connect.						U.S. Only					w/ Vent		w/o Vent				Vent
	Nat.		Propane		Size		A			B	(Outdoor)					Damper)		Damper)				Dia.
Size	in.	mm	in.	mm	in.	mm	in.	mm	in.	mm	in.				mm	in.	mm	in.			mm	in. mm
175	¾	19	½	13	1½	38	18	457	26½	673	14	1	/	16	357	28½	724	23½			597	6	152
250	¾	19	½	13	1½	38	22½	572	31	787	18	1	/	16	473	30½	775	24¾			629	7	178
325	¾		½		1½		26¾		35¾		19		/			—	—	25		/		8
		19		13		38		679		908		3		16	488				7		657		203
400	¾	19	½	13	1½	38	31¾	806	40¼	1022	22		/		575	—	—	26		8	683	9	229
												5							7	/
														8						8

*Vent damper only required on indoor installations, sizes 175 and 250. Note: Dimensions may vary.

Figure 1. General Configuration.

Page 4	LAARS HEATING SYSTEMS

SECTION 2.

Installation Instructions

2A. General Information

WARNING

Follow local regulations with respect to installation of carbon monoxide (CO) detectors and manufacturer's maintenance schedule of the boiler.

Install the HH-PH boilers in accordance with the procedures in this manual (or the Laars warranty may be voided), local codes and ordinances. In the absence of such codes, install the boilers in accordance with the latest edition of the National Fuel Gas Code, ANSI Z223.1. In Canada, the installation must be in accordance with CAN1-B149.1 or .2 and local codes. The authority having jurisdiction may require the installation conform to the Standard for Controls and Safety Devices for Automatically Fired Boilers, ANSI/ASME CSD-1. Any changes to the boiler, gas controls, gas orifices, wiring or draft hood may void the warranty. If field conditions require change, consult the factory.

All gas-fired products require correct installation to assure safe operation. The requirements for boilers include the following:

1.Field assembly of draft hood and vent cap (if required – see Section 2B)

2.Appropriate site location (clearances) and flooring

3.Sufficient combustion and ventilation air

4.Adequate venting of combustion products

5.Adequate water flow

6.Properly sized gas meter and piping

7.Proper electrical wiring

This manual provides the information needed to meet these requirements. Review all application and installation procedures completely before continuing the installation.

2B. Field Assembly

The HH-PH boiler is shipped from the factory with the top assembly in the low-profile configuration for outdoor installations.

The HH-PH boiler is design certified for indoor installation when equipped with a drafthood, which must be installed without modification. Check the rating plate on the boiler for the correct Laars part number.

Follow this procedure to make the conversion:

a.Remove the top filler plate, stamped “HOT,” by slipping a fine-blade screw driver into the slot at

T

HO

Figure 2. Top Filler Plate.

Figure 3. Adapter Plate.

the rear of the plate and gently prying it up (see Figure 2).

b.Remove the two screws attaching the adapter plate to the top assembly and lift it out (see Figure 3).

c.Remove the vent cap or drafthood from its package.

d.Disengage the flue transition ring from the stack extension and place it on top of the collector assembly as shown in Figure 4.

Figure 4. Flue Transition

Ring.

Figure 5. Vent Cap with Adapter Plate

e.Slide the adapter plate over the bottom of the stack extension as shown in Figure 5. Fit the stack extension down over the flue transition ring. Seat the adapter plate on the top assembly and secure it with two screws (see Figure 6).

f.Find the vent damper box which is located in the boiler package (boiler models 175 to 250 only) (see Figure 8).

g.Install the vent damper directly to the top of the draft hood outlet. The damper operator should face to the front of the boiler, and the flow direction arrow should point upward. Use the vent damper wire harness to connect the vent damper to the boiler. The bracket end of the harness should be connected to the vent damper actuator.

Mighty Therm HH-PH Hydronic Boilers	Page 5

Figure 6. Drafthood with

Adapter Plate.

Figure 7. Drafthood Switch

Receptacle.

h.Plug the wiring for the drafthood switch into the receptacle on the left side of the vent damper box (see Figure 7).

i.Do not modify the automatic vent damper device. The venting system must be arranged so that only the boiler is served by the vent damper device supplied with the boiler. Provide at least six inches clearance between the automatic vent damper and combustible construction, and be sure to allow access for servicing the damper.

WARNING

Do not force motor operation when the operator is fastened to the damper by moving the damper blade, turning the shaft, or turning the position indicator.

VENT DAMPER

DRAFT HOOD

VENT DAMPER HARNESS

2C. Site Location

2C-1. Installation Information

WARNING

Improper installation or maintenance can cause nausea or asphyxiation from carbon monoxide in flue gases which could result in severe injury, property damage, or death.

Locate the boiler to provide clearances on all sides for maintenance and inspection. There must also be minimum distances maintained from combustible surfaces (see Table 1 and Figure 9).

	Indoors		Outdoors
Clearance from:	inch	mm	inch	mm
Top	37	940	Unobstructed
Water conn. side	12	305	Unobstructed
Opposite side	6	152	6	152
Front	Alcove		Unobstructed
Rear	6	152	6	152
Vent*	6	152	—
Flooring	Combustible		Combustible

Service clearance = 36 inches (914mm) at front of heater, and 18 inches (457mm) at water connection side.

*1" (25mm) if double wall vent is used.

Table 1. Minimum Boiler Clearances

From Combustible Surfaces.

Heater

Closet Installation	Room Installation
(unacceptable)	(acceptable)
A closet is any 4 sided enclosure	A room is any enclosure which is
which is less than 16* times the	at least 16* times greater than the
total volume of all the gas fired	total volume of all the gas fired
appliances within the enclosure.	appliances within the enclosure.

Alcove Installation

(acceptable)

Heater	An alcove suitable for the
	installation of a heater is a
	restricted section of a room not
	separated from the room by a door
	or partition and which meets the
	minimum clearances specified in
	this manual.

* When the cieling height exceeds 8 feet, you are only allowed to consider 8 feetwhen calculating the total volume of the enclosure.

Figure 8. Vent Damper Installation (Models 175 and	Figure 9. Alcove Installation.
250 only).

Page 6	LAARS HEATING SYSTEMS

The boiler must be isolated or otherwise protected from any source of corrosive chemical fumes, such as trichlorethylene, perchlorethylene, chlorine, etc. Install the boiler so that the gas ignition system components are protected from water (drippings, spraying, rain, etc.) during operation and service. Locate the boiler on a waterproof floor with a floor drain and a 6 inch (152 mm) minimum curb on all four sides to protect the building if boiler repairs are needed.

2C-2. Outdoor Installation (U.S. Only)

Caution

Outdoor installations are not recommended in areas where the danger of snow blockage exists. HH-PH boilers can be installed in the “low-profile,” grate top configuration as received from the factory, or with an optional vent cap/stack.

Locate the boiler in an open, unroofed area. Do not locate the boiler below or adjacent to any doors, windows, louvers, grills, etc., which connect in any way with an inhabited area of a building, even though the access might be through another structure such as a garage or utility room (see Figure 10 and Table 1).

WINDOW

OR GRILL

INDOOR

ROOM

Figure 10. Incorrect Outdoor Installation.

	4 ft.
	(1.2 m)
4 ft.	4 ft.
(1.2 m)	(1.2 m)

Figure 11. Outdoor Location.

There must be a minimum of 4 feet (1.2 m) horizontally between the boiler and any door, window, or gravity inlet to a building (see Figure 11). Also, the horizontal clearance should be maintained from any electric meters, gas meters, regulators, or relief equipment.

If the boiler is installed close to a structure, protect it from rain water runoff with rain gutters on the roof or other measures. Do not locate the boiler near sprinkler systems that could spray water on it. Avoid locations where wind deflection off

nearby structures might cause wind loading and downdraft conditions. Where downdraft conditions exist, locate the boiler at least 3 feet (0.9 m) from the structure.

2C-3. Flooring - Typical Installation

All boilers are equipped with a special base, as a standard part of the boiler. The unit is designed and certified for installation on combustible flooring. Never install the boiler on carpeting. Never store objects on or around the base of the boiler.

For rooftop installation, see Figure 12 through Figure 14.

Figure 12. Standard Base for Combustible Floor.

Figure 13. Typical Roof Mounting with Standard Combustible Mount Base.

Mighty Therm HH-PH Hydronic Boilers	Page 7

Figure 14. Typical Roof Mounting.

2D. Combustion and Ventilation Air Supply

All indoor installations must have openings to outside air for combustion, ventilation and dilution of flue gases from inside the building (see Figure 15 and Table 2). Laars does not recommend indoor installations that do not provide combustion air from outside the building.

Boiler rooms which are confined spaces require two permanent air supply openings: one within

12 inches (305 mm) of the ceiling, the other within 12 inches (305 mm) of the floor.

Notes:

1.The drafthood must sit directly on top of the boiler as shown and must not be altered in any manner.

2.An Underwriters' Laboratories listed vent cap is required to eliminate downdraft and allow the boiler to function properly.

3.Use approved roof fitting.

4.Vent damper is required on models 175 and 250.

Figure 15. Indoor Installation Venting.

		Required Net Free Opening Area
			Directly from Outside
	Model		At Top	At Bottom
		in.2	cm2	in.2	cm2
175		44	284	44	284
250		63	406	63	406
325		82	529	82	529
400		100	645	100	645

Note: For screens or louvers, add 50%.

Table 2. Air Openings to Outside.

NOTE: Check with louver manufacturers for net free area of louvers. If not available, add 50 percent for each screen/louver to the net free area. Check all local codes applicable to combustion air.

2D-1. Outdoor Air Supply

When combustion air comes directly through an outside wall, each opening must have a minimum free area of at least one square inch for each 4,000 BTU/h input of the total input rating of all appliances in the enclosed area. (In Canada, refer to CGA B149.1

and .2.)

2D-2. Indoor Air Supply

Confined and non-confined areas have different requirements for installation. Consult the latest edition of the National Gas Code for installation requirements.

2D-3. Exhaust Fans or Vents

Any equipment which uses air or removes air from the boiler room can use up the combustion air supply or reverse the natural draft action of the venting system. This could cause flue products to build up in the boiler room. More air must be supplied to make up for the decrease. This must be designed by a qualified engineer.

2E. Venting of Combustion Products

2E-1. General Information

When installed indoors, the drafthood and the vent damper device (models 175 and 250) must be connected to a venting system without alteration. The venting system must be installed by a qualified installer and in accordance with the latest edition of ANSI Z223.1. In Canada, the installation must be in accordance with CAN1-B149.1 or .2, and any local codes that apply.

The vent pipe must have a listed vent cap and extend at least 2 feet (0.6 m) above any object within a 10 foot (3.0 m) radius (see Figure 15).

Page 8	LAARS HEATING SYSTEMS

NOTE: Do not use sheet metal screws at the snap lock joints of Type B gas vents.

Do not weld or bolt the vent pipe to the boiler drafthood or the vent damper if one is installed. The weight of the stack must not rest on the boiler. The drafthood and boiler top must be easily removable for normal boiler service and inspection.

WARNING

Avoid ending boiler vents near air conditioning or air supply fans. The fans can pick up exhaust flue products from the boiler and return them inside the building, creating a possible health hazard.

Avoid horizontal runs of the vent pipe, and 90 degree elbows, reductions and restrictions. Horizontal runs should have at least a ¼ inch (6 mm) rise per foot in the direction of flow. Support a vent connector for the design and weight of the material used to maintain clearances and prevent physical damage and separation of joints.

Always use double-wall or insulated vent pipe (Type B or equivalent).

WARNING

In cold weather, uninsulated outside vents can chill the rising flue products, blocking the natural draft action of the venting system. This can create a health hazard by spilling flue products into the boiler room.

Avoid oversize vent piping or extremely long runs of the pipe which may cause too much cooling and condensation of flue gasses.

2E-2. Replacement of Existing Boiler

At the time of the removal of an existing boiler, the following steps shall be followed with each appliance remaining connected to the common venting system. During the testing of each unit, the other appliances remaining connected to the common venting system should not be operated.

1.Seal any unused openings in the common venting system.

2.Visually inspect the venting system for proper size and horizontal pitch. Determine that there is no blockage or restriction, leakage, corrosion, or other deficiencies which could cause an unsafe condition.

3.As far as possible, close all building doors and windows. Also close all doors between the space in which the appliances remaining connected to the common venting system are located and the other spaces of the building. Turn on any clothes dryer and any appliance not connected to the common venting system. Turn on any exhaust

fans, including range hoods and bathroom exhausts, so they will operate at maximum speed. Do not operate a summer exhaust fan. Close all fireplace dampers.

4.Place in operation the appliance being inspected. Follow the lighting instructions for the unit. Adjust the thermostat so the appliance will operate continuously.

5.After 5 minutes of main burner operation, test for spillage at the draft hood relief opening. Use the flame of a match or candle, or smoke from a cigarette, cigar, or pipe.

6.The tests should show that each appliance connected to the common venting system vents properly. Return all doors, windows, exhaust fans, fireplace dampers and any other gas-burning appliances to their previous condition of use.

7.Any improper operation of the common venting system should be corrected. The installation should conform with the National Fuel Gas Code, ANSI Z223.1. When resizing any portion of the common venting system, the system should be sized to approach the minimum practical size. Refer to the tables in Appendix G in the National Fuel Gas Code, ANSI Z223.1. (In Canada, at the time the boiler is removed from the common venting system, the common venting system should be resized. The installation should conform to CAN/CGA B149.1 or .2.)

2F. Water Flow System

2F-1. Reversible Water Connections

NOTE: This procedure is not recommended for the PH pump-mounted models.

Laars ships the HH boiler with the water connections on the right side. The HH boiler can be installed with the water connections on either side. It could be necessary, or helpful, to switch the connections to the left side to improve access for installation service. Perform this modification before installing the boiler using the following procedures:

1.Remove the front door.

2.If there is a vent cap or drafthood installed, it must be removed before removing the grate top assembly. On indoor installations (models 175250), the drafthood switch must be disconnected at the vent damper receptacle on the left side of the boiler.

3.If the unit is in the low-profile outdoor configuration, remove the hex-head screws (see Figure 16) and lift the top assembly straight up.

4.Remove the screws that fastens the flue collector hold-down clamps and remove the clamps (see Figure 17).

	Mighty Therm HH-PH Hydronic Boilers			Page 9
			REAR TILE COVER
	HEAT EXCHANGER		FLOW SWITCH
	ASSEMBLY
	DRAIN PLUG		CONDUIT
	DRAIN VALVE
	REAR TILE
	COVER
		GAP CLOSURE
			GROMMET
				DRAIN
	HEX HEAD			VALVE
	SCREWS	METAL CHANNEL
	MANUAL RESET
		(FOR CAPILLARY TUBE)
	HIGH LIMIT
	SWITCH BOX
		TERMINAL STRIP

Figure 16. Heat Exchanger Removal.

Clamp

Flue Collector

Bracket

Clamp

In/Out Header

Heat Exchanger

Bracket

Figure 17. Flue Collector Holddown Clamps.