Glowworm Lighting 40 manual Water System

2 Water System

Note.

The boiler has 28mm copper connections, which can be reduced to 22mm for the Energysaver 40, provided the system resistance does not exceed the chosen pump duty.

2.1 Draining Tap

The boiler is provided with a draining point at the lower left hand side of the burner manifold, to be used for draining the boiler, see diagram 2.1.

A draining tap must be provided at the lowest points of the system which will allow the entire system and hot water cylinder to be drained.

Draining taps shall be to the current issue of BS2879.

2.2 Safety Valve

A safety valve need not be fitted to an open vented system.

2.3 Pump

The pump should be fitted in the flow pipe from the boiler and have isolating valves each side, integral if possible.

A variable duty pump should be set to give a temperature difference of 11oC (20oF) between the flow and return, with the thermostat set at “MAX”, which is about 82oC (180oF), to give a design flow rate as shown in Table 3.

See chart for pressure drop of the boiler, diagram 2.2.

High resistance microbore systems may require a higher duty pump.

2.4 Bypass

A BYPASS MUST BE FITTED, see diagram 2.3 for a suitable position.

The flow rate through the boiler must not be allowed to fall below that given in Table 3.

Where the water system can allow the boiler and pump to operate on bypass only, the bypass must be placed at least 1.5m away from the boiler.

2.5 Inhibitor

Attention is drawn to the current issue of BS5449 and BS7593 on the use of inhibitors in central heating systems.

If an inhibitor is to be used, contact an inhibitor manufacturer for their recommendations as to the best product to use.

Note: This boiler has a totally copper water system and does not require a special inhibitor normally associated with other types of high efficiency (“condensing”) boilers.

If an existing system is to be reused take special care to drain the entire system, including the radiators, then thoroughly cleaning out before fitting the boiler whether or not adding an inhibitor.

2.6 Open (Vented) Water System

The boiler must be supplied from an unrestricted water supply taken from a feed and expansion cistern situated at a maximum height of 27metres (90ft) above the boiler.

The cold feed must be 15mm minimum size.

The vent must rise continuously and be unrestricted.

It is important that the relative positions of the pump, cold feed and open vent are as shown in diagram 2.3.

4042

BOILER

DRAIN

POINT

Diagram 2.1

		0	1	2	3	4	5	6	7	8			0164M
			Flow rate (gallons/minute)
		2.0
losspressure	water)ofhead										70	losspressure	water)ofhead
		1.5									60
											50
		1.0									40
Water	(metres										30	Water	(inches
		0.5									20
											10
		0									0

05 10 15 20 25 30 35 40 Flow rate (litres/minute)

		Diagram 2.2
	TABLE 3
	Design	Minimum
	Flow Rate	Flow Rate
Energysaver 40	15.5L/min	11L/m

2.7 Domestic Hot Water Cylinder

The domestic hot water cylinder must be of the double feed fully indirect type. Not the single feed self priming type.

2.8 Domestic Hot Water System - Unvented

Where a storage system will not have a vent to atmosphere the installation must comply with the Building Regulations and local Water Company bylaws, see also the current issue of BS5546 and BS6700.

If fitting to an existing system the local authority should be informed.

2.9 Sealed Water Systems

The installation must comply with the appropriate requirements of the current issue of BS4814, BS5449, BS6759, BS6798 and BS7074 Part 1 and 2.

See diagram 2.4 for a suggested layout.

221834B 8