Pentair MT Sizes 500 Winter Operation Complete Shutdown, Time Clock Operation

Page 14 Pentair Water Commercial Pool and Spa

and 1825 pool temperature should be maintained at 70°F (21°C) or above. See item 3 in the next section.

7.An adjustable pump time delay relay is mounted in the control panel (see Figure 11). This relay keeps the pump running after the burners shut off. The delay should be set to 5-6 minutes for models 500-850 and 9-10 minutes for models 1010-1825.

3.7Winter Operation Complete Shutdown

1.To shut down the heater for periods of several months or more, turn manual main gas valve and pilot gas valve to "OFF." Where danger of freezing does not exist, some water should flow through the heater during the normal filter cycle all year long, even when the heater is turned off or shut down completely, if all bypass valves are opened.

2.If the heater is not protected from freezing temperatures, it should be completely drained before the first frost. Drain the heater by removing the drain plug on the bottom of the front header casting. Leave the plug out until ready to use the heater again. Heater must be level to permit adequate draining. When compressed air is used to blow out lines, it is still necessary to follow the above procedure. Keeping the pool heated and the filter pump running continuously will not be adequate protection. If there is a pump failure or an electrical power failure, the boiler cannot fire and may freeze and be damaged.

3.Improper Use of Heater: The heating boiler is not designed for continuous use as an "anti- freezing" device for pools. Operating the heater with low water temperatures will cause the fins on the heat exchanger to be partially blocked with condensation. Incomplete combustion and prolonged operation under these conditions will result in the heat exchanger sooting up. This can seriously damage the heater and may create a dangerous fire hazard.

3.8 Time Clock Operation

During the warm-up period, the heater must run continuously so it can raise the pool temperature from cold to above 70°F (21°C).

Remove all time clock stops and permit the heater to raise pool temperature to 70°F (21°C) or above in one continuous operation.

When the time clock stops are replaced, be sure to allow the filter pump and the heater to stay on long enough to keep the pool up to the desired temperature.

3.9 Therapeutic Pools (Spas)

Therapeutic pools or "spa" pools are usually piped and controlled so that very warm or hot water, often with air injection, is forced at high velocity into a confined area of a swimming pool or into a small separate pool. For the purposes of this manual, any application in which the water temperature is maintained above 85°F (30°C) is considered a spa.

SPECIAL SET-UP AND OPERATING PROCEDURES APPLY TO SPAS.

1.Models 1010I and 1010E and larger should not be used for spas due to their higher temperature rises.

2.Since outlet temperatures can approach 140°F (60°C) units must be piped in a primary- secondary style, similar to that shown in Figure 10.

3.To insure that the spa inlet water does not exceed 104°F (40°C), the spa filter pump must circulate at the minimum flow rates shown in Table 5.

Boiler Model	Minimum Filter Pump Flow Rate
500	220 GPM
600	270 GPM
715	320 GPM
850	380 GPM

Table 5. Minimum Filter Pump Flow Rates For Spas.

Note: Maximum Spa Temperature Is

Assumed To Be 100°F (38°C).

4.The high limit stop should be changed to 140°F (60°C). The set point should then be checked following the procedure in 3.3.

5.Use the outlet valve “A” to set the inlet temperature per section 3.4.

6.Spas are excellent for relaxation, body- conditioning and for arthritic and rheumatic problems, but can be hazardous. The Consumer Product Safety Commission has recommended the following "Safety Rules for Hot Tubs:"

a.Spa or hot tub water temperature should never exceed 104°F (40°C). A temperature of 100°F (38°C) is considered safe for a healthy adult. Special caution is suggested for young children.

b.Drinking of alcoholic beverages before or during spa or hot tub use can cause drowsiness which could lead to unconsciousness and subsequently result in drowning.

c.Pregnant women beware! Soaking in water above 102°F (39°C) can cause fetal damage during the first three months of pregnancy (resulting in the birth of a brain-damaged or deformed child). Pregnant women should stick to the 100°F (38°C) maximum rule.

d.Before entering the spa or hot tub, users