Technical data

TECHNICAL AND INSTALLATION
8
5. MAINTENANCE
ACV recommend that the cylinder is maintained by a competent person, this should be carried out
every 12 months.
The safety valves must be manually operated at least once a year to check their operation and re-
seating. Allow cylinder to cool before slowly twisting open the temperature and pressure relief
valve. The water should flow freely through the tundish and discharge pipe work, check that the
valve reseats when released.
CAUTION: The water discharged may be very hot.
Repeat the steps above for the expansion relief valve on the cold inlet pipe work.
The pressure reducing valve (PRV) has a strainer that can be removed for inspection and if
necessary cleaning.
i. Isolate the cold water inlet to the cylinder.
ii. Open the lowest hot tap to remove the pressure from the system.
iii. The black plastic PRV cartridge can be unscrewed from the brass valve body, loosen
using a suitable spanner (not stilsons or pump pliers) unscrew and pull the cartridge from
the valve body, the strainer will be withdrawn with the cartridge.
iv. Remove the strainer from the cartridge and clean under running water if necessary.
v. Replace strainer and push cartridge into valve body, take care when screwing the cartridge
in not to damage the threads. Do not over tighten.
vi. Close hot tap and slowly open the cold water isolating valve to the cylinder, check for any
leaks.
The primary tank should be checked for a build up of air, this can be purged using the primary air
vent on the top of the cylinder. Check the primary system pressure gauge on the boiler or filling
loop and recharge as necessary.
IMPORTANT: If the primary system is being topped up on a regular basis there is a risk of
corrosion damage to the cylinder.
The tank must be fitted by means of screwed couplings or flanges to allow dismantling and
removal of the unit. These should be fitted in such a way as to allow easy access.