燃氣熱水鍋爐啟動前進水速度不宜太快，一般冬季不小于4h，其他季節不小于2 ~ 3h，尤其在進水初期應緩慢。燃氣熱水鍋爐的進水溫度一般為50-90℃，因此進入汽包的給水溫度與汽包壁溫相差不超過40℃。對于沒有有效冷卻的燃氣熱水鍋爐，進水溫度可與汽包壁溫相比較，否則進水速度應減慢。
The water speed of gas-fired hot water boiler should not be too fast. Generally, it should not be less than 4H in winter, and not less than 2 ~ 3H in other seasons, especially in the early stage of water inflow. The water inlet temperature of gas-fired hot water boiler is generally 50-90 ℃, so the difference between the water supply temperature entering the drum and the wall temperature of the drum is not more than 40 ℃. For the gas-fired hot water boiler without effective cooling, the water inlet temperature can be compared with the drum wall temperature, otherwise the water inlet speed should be slowed down.
When the water enters the drum, it always contacts the lower half of the drum first. If the difference between the temperature water supply and the drum wall is too large, the water speed is fast, the drum, the upper and lower walls, the inner and outer walls will produce a big difference in expansion, the drum will cause more additional pressure, leading to the deformation of the drum and serious cracks.
Because the drum wall is thick, the expansion speed is slow, while the tube connected to the drum wall is thin and the expansion speed is fast. If the water inlet temperature of the gas-fired hot water boiler is too high or the water inlet speed is too fast, it will cause uneven expansion, crack of the welding joint, and damage the gas-fired hot water boiler.
壓力管的直徑一般取7 ~ 13mm(對于水、蒸汽)，其長度不宜過長(<60m)。如果壓力管的直徑過小，長度會影響壓力測量的動態傳遞，增加動態誤差。內徑大，不易維修，安裝方便。壓力管線不能水平敷設，以防止氣泡(測量液體時)和水柱(測量氣體時)的積聚。出口必須垂直于介質流。不允許倒角、法蘭和毛刺進入口內。測量電加熱蒸汽鍋爐的液體壓力時，應將壓力出口從管段下部抽出，防止液體中的氣體進入壓力管道。測量氣體壓力時，應將噴嘴從管段頂部抽出，以防止灰塵和水滴進入壓力導管。
The diameter of the pressure pipe is generally 7 ~ 13mm (for water and steam), and its length should not be too long (< 60m). If the diameter of the pressure pipe is too small, the length will affect the dynamic transmission of the pressure measurement and increase the dynamic error. Large inner diameter, not easy to maintain, easy to install. Pressure lines should not be laid horizontally to prevent the accumulation of air bubbles (when measuring liquids) and water columns (when measuring gases). The outlet must be perpendicular to the medium flow. Chamfers, flanges and burrs are not allowed to enter the mouth. When measuring the liquid pressure of the electric heating steam boiler, the pressure outlet shall be drawn out from the lower part of the pipe section to prevent the gas in the liquid from entering the pressure pipe. When measuring the gas pressure, the nozzle should be pulled out from the top of the pipe section to prevent dust and water from entering the pressure conduit.、
The installation position of pressure gauge of electric steam boiler (pressure transmitter) shall meet the environmental conditions (temperature, humidity, vibration, etc.) used by the instrument, so as to facilitate observation, maintenance and safety. Thermal insulation layer must be laid in the high-temperature medium pressure pipeline to prevent scalding when flushing the pipeline.
The penstock must be equipped with a needle valve operation (failure to cut off the penstock), a secondary needle valve (active instrument put into use, stop, change), a condensation coil and an elbow (high temperature isolation of elastic elements from the medium, convenient addition of sealing plate packaging), a drain valve and a drain pipe, etc. For special pressure measurement, the pressure pipe must also be equipped with exhaust valve, isolation chamber, etc.