Module 18 Domestic Space Heaters

Question 1

Name the four common types of gas heaters

Answer 1

1. Radiant
2. Live Fuel Effect (LFE)
3. Decorative Fuel Effect (DFE)
4. Flueless

Question 2

For a radiant gas fire what flue size and ventilation requirements are typically required?

Answer 2

Flue – >125mm across
Vent - <7kW usually 0
>7kw – 5cm2 per kW

Don’t forget to factor in adventitious air!

Plus some are R/S

Question 3

For a LFE gas fire what flue size and ventilation requirements are typically required?

Answer 3

Flue – >125mm across
Vent - <7kW usually 0
>7kw – 5cm2 per kW

Don’t forget to factor in adventitious air!

Question 4

For a DFE gas fire what flue size and ventilation requirements are typically required?

Answer 4

Flue - >175mm across
Vent - >100cm2

Question 5

For a flueless gas fire what flue size and ventilation requirements are typically required?

Answer 5

For a flueless gas fire what flue size and ventilation requirements are typically required?

Question 6

What is the difference between a simplex and a duplex burner?

Answer 6

Simplex – single injector, Simplex tap
Duplex – two injectors, Duplex tap (more flexibility)

Question 7

In modern gas fires the permanent pilot has often been replaced with what sort of ignition mechanism?

Answer 7

Piezo ignition

Question 8

For gas fires, other than DFEs, how long can FSDs take to shut down?

Answer 8

180 seconds

Question 9

On modern gas fires what is the most common type of FSD?

Answer 9

Thermo-electric valve
(electro-magnetic unit connected via thermocouple to pilot burner assembly)

Question 10

What does an atmospheric sensing device (ASD) do?

Answer 10

If oxygen levels fall the flame lifts from the thermocouple unit and the unit shuts down

Question 11

What type of gas fire does the image depicit?

M18/p12

Answer 11

Room sealed radiant convector fire

Question 12

Flueless gas fires – how to they avoid poisoning people?

Answer 12

Catalytic convertor on the flue

Question 13

What type of gas fires can be installed in Bath/shower rooms?

Answer 13

Room sealed – restricted locations

Question 14

Can an O/F gas fire be installed in a bathroom?

Answer 14

No

Question 15

What type of gas fires can be installed in private garages?

a) Flueless
b) O/F
c) R/S
d) b + c
e) None of the above

Answer 15

d) b+c

Question 16

If you install a gas fire and boiler in a bedroom do you factor in the combined kW or just each kW when choosing between an O/F and a R/S

Answer 16

It is the combined value. >14kW Gross then it must be R/S

Question 17

If there is a gas fire in the bedroom what are the rules?

a) None
b) >14kW gross – R/S
c) <14kW gross – O/F
d) <14kW gross – O/F + ASD
e) b+d

Answer 17

e) b+d

Question 18

A room containing a flueless space heater – should there be an opening window or not?

Answer 18

Yes there should or an equivalent e.g. fixed air vent

Question 19

If a greenhouse heating exceeds 2.7kW (net) is additional ventilation required?

Answer 19

Yes - one high, one low, 39cm2 per kW in excess of 2.7!

Question 20

Name two key issues when installing a gas fire in a conservatory on a brick wall and concrete floor.

Answer 20

Condensation
Carbon monoxide alarm

Question 21

What is the usual ventilation requirement for a DFE up to 20kW in a room?

Answer 21

100cm2

Question 22

What are the usual ventilation requirements for two DFEs, up to 20kW in a room?

Answer 22

235cm2 (100+100+35 adventitious air for the 2nd DFE)

Question 23

What are the usual ventilation requirements for a DFE and other types of appliances in a room

Answer 23

100cm2 for the DFE + the greatest of:

1) All O/F space heaters – 5cms/kW(net)
2) Total flueless space heating requirement e.g. hall convector heater
3) Largest O/F non space heater 5cm2/kW(net) e.g. water heater

Question 24

What are the usual ventilation requirements for a DFE and other types of appliances in a through room with two flues

Answer 24

100cm2 for the DFE + the greatest of:

1) All O/F space heaters >7kW = 5cms/kW(net)
2) Total flueless space heating requirement e.g. hall convector heater
3) Individual flueless “other” appliances
4) Largest O/F non space heater >7kW =5cm2/kW(net) e.g. water heater

Question 25

What are the usual ventilation requirements for two DFE and other types of appliances in a through room with two flues

Answer 25

235cm2 for the DFEs + the greatest of:

1) All O/F space heaters 5cms/kW(net)
2) Total flueless space heating requirement e.g. hall convector heater
3) Individual flueless “other” appliances
4) Largest O/F non space heater 5cm2/kW(net) e.g. water heater