Energy efficiency in your hands
Thermostat range
On/Off Control
Specifications at a glance
SET POINT
On/Off control is the method of control used by most heating systems in the UK. The
controls simply switch mains current supplied to the boiler on or off at different times.
†
On/Off thermostat control
Time Proportional + Integral control (TPI) is a method of calculating the demand from a room thermostat, controlling the boiler so that it fires for shorter periods as the temperature approaches the set point. This is an industry standard term, describing
SET POINT
a mathematical calculation of demand. TPI allows the flow temperature from the boiler to fall as demand reduces, which, in turn, helps the return temperature to stay below the Dew Point (55oC) so that the
DT92E
Load Compensation and currently accrues a 3% boiler efficiency increase under the TPI thermostat control
Modulating Control
CM957
Modulating
Temperature range ( C) 10-30
10-30
5-35
5-35
5-35
5-35
5-28
Y6630D1007
24-230V AC, 5A resistive
DT90E
DT90E1012
24-230V AC, 8(3)A
DT92E
DT92E1000
24-230V AC, 5A resistive
OpenTherm, a Honeywell invention that has been made into an open standard for
CM901
CMT901A1044
24-230V AC, 8A resistive
all to use.†
CM907
CMT907A1041
24-230V AC, 8A resistive
CM921
CMT921A1042
24-230V AC, 5A resistive
CM927
CMT927A1049
24-230V AC, 5A resistive
Many boiler and control manufacturers now recognise the energy savings potential
T87
T87M1029
n/a
of modulating control, so have adopted OpenTherm as the best method to control a
Y87RF
Y87RFXXXX
n/a
CM937
CMT937A1027
n/a
CM957
CMT957A1009
n/a
demand signal. The most common protocol used for modulating control of modulating boilers is
Modulating control
5-28
P P P P
1
3 yrs
Y6630D
SET POINT
7 2 yrs
10(3)A
Instead of switching a boiler on and off at intervals, the modulation of the gas valve
1 2 yrs
T6360B1036*
Small change... big effect with thermostats working to close control, further large
CM937
2 yrs
T6360
†
Y87RF
4 yrs
Switch Rating
heating system efficiently.†
T87
2 yrs
o
Full Part Number
OpenTherm
CM927
Battery life
Product
Modulating control is a method of control used by modern heating systems in the UK. allows the amount of heat provided by the boiler to be controlled to match the varying
CM907
P TPI On/Off P P P P P OpenTherm modulation P P P Wired P P P P P Wireless P P P Wireless 2 way P Load compensator P P P P P P P P Optimum start P P P 1 day/7 day
boiler can operate in condensing mode more frequently. This effect is referred to as SAP calculations.†
DT90E
Standard On/Off
the boiler to burn whilst there is a live supply to it. When the current is interrupted, the
TPI Control
Y6630D
On/Off Feature
When the controls switch on, the current opens the gas valve, strikes a spark and allows boiler ceases to fire.
T6360
Thermostat Range
7
5-35
5-35
OpenTherm®
OpenTherm®
* Other models available
en
e r g y s a v i ng
Small change... big effect
savings can usually be made without any loss of comfort by reducing the set point.
Honeywell Honeywell House, Bracknell Berkshire, RG12 1EB Tel: 01344 656000 Fax: 01344 656240 E-mail: uk.infocentre@honeywell.com www.honeywelluk.com
HW Thermostat 6pp.indd 1-3
EN3H-2901 UK01 R0409
16/03/2009 10:39